A Sirius Matter -Plus-DOUBLE STAR TIPS -

[bigjoe]

For the last few nights whilst observing the GRS and some of my favourite doubles, eg- Iota Cancri ,145 Canis Majoris, and Beta Monocerotis; I thought to myself, why not have a crack at Sirius B, AKA the "PUP".

The first two nights proved fruitless due to the less than excellent seeing required; still I persisted till midnight on the 24th at my house in Concord , even though work beckons in the morn.

The "PUP" being about some 10.5" from the primary. If you can imagine Sirius A being at the center of a clock then Sirius B would be at 9 oclock - East or a little North of that; but this depends on the scope and diagonal used, my 2" di-electric is reversed East-West but upright, so it would be on the West side then.

At magnitude 8.6 with the glare of Sirius A it should prove very difficult and it was.

I tried all kinds of tricks , including letting Sirius A drift in or out of the field of view so its glare would be mitigated and the PUP easier to see, filters including red, also observing at twilight so A would be less brilliant compared to B, even thought of making an obstruction mask.

Success though came at midnight when there were moments of steady seeing , just past the meridian; it was here that I inserted a 17.3 Delos in a 7" Mak I have - no luck, then I tried a 13mm type 6 Nagler, still no luck; it was then that I decided to use one of my old style Parks 5mm Gold series EP for a lark -VOILA!!

There it was very faint, and well outside the diffraction rings -unmistakable; this was at a mag of about 560x!!!

I had been looking in the diffraction rings mostly and not so much outside with all these EP'S, and this is what you must do plus highish power at this separation now, to literally separate the "PUP" from the primary.

Im glad I have finally bagged this elusive object after all these years of half hearted attempts.

It would be interesting to see if others, esp with apo's have a crack also.

PS: Ghosting sometimes appears and you think you have found it - but alas - so keep at it!

Cheers bigjoe.

[skysurfer]

This is a real challenge.

Yesterday night I tried with the ED110 with a WO dielectric diagonal and an LV6 eyepiece (128x), but lots of speckles and NO Sirius B. Maybe the seeing can be better ?

[bigjoe]

Loverly setup you have Skysurfer.

I wouldn't give up though, the diffraction rings have to be unbroken concentric, so very good seeing near the meridian, even if fleetingly is all you need, and higher power probably double what you've used to separate the PUP from the primary.
Your equipment should be ideal for this :thumbsup:
Keep it going.
PS: Seeing is everything here; absolutely no speckling-it will mask the PUP.

Cheers bigjoe.

[The Mekon]

Good observation Joe - I will pay that one. So many reports of Sirius B I count as "spurious" - especially those North American reports on CN where the elevation is low.

If you cannot easily pick up the companion of nearby Adhara with a mag of around 100X, then you will have no chance of Sirius B.

I have only seen it a couple of times with my masked off 18", and magnification of 292X

[Tinderboxsky]

An excellent result Joe. Lots of patience and perseverance are the keys to bagging difficult targets as you have shown.
I have had two serious attempts this summer to observe the Pup, but no success to date. Shall "persevere"!

Steve.

[multiweb]

Had a go at it in December last year. Very hard to get. I don't know how you guys do it visually. It was up close to the zenith and the seeing was very good.

[bigjoe]

On a work break so I though I would write on some of these nice responses.
Thanks John, Steve and Marc.

I agree that most reports would be spurious as it seems next to impossible at times to see it ; could it be ghosting etc. I found that I had to nudge the EP a number of times and use averted vision to confirm, also at times -it's sooo faint in comparison to the primary its not funny.

I would imagine that expecting to see it anywhere away from near zenith would be impossible visually.

When using the Mak I felt; if you cannot drive a Mak truck (pun intended)
through Rigels loverly pair as a test- then don't bother, as that is what i'd done just prior, and my wife was in awe of this pairs colour contrast.

Rigel has a similar separation so I though, why not try again!

The PUP appeared perhaps the colour of a tiny Uranus to my eyes past all the diffraction rings just were it should be -one of the biggest astro thrills of my life-When I was a youth circa 1980, I remember reading people with 6" unitrons had seen it- I only had the 4" (from AOS) at the time - of course no luck.

So Steve and all it's doable, but next to impossible at the same time,
most would be left in utter frustration I feel and just give up thinking what do I have to do; well nothing really, but WAIT for the right conditions, and I would say high magnifications well above 200x in apertures above 4" as it is very faint- seems less than 8.6 because of the primary.

So good luck all out there, and as usual- GIVE DOUBLES A GO!!

Cheers bigjoe.

[MattT]

I reckon this is one that once you see it it's impossible to miss thereafter.
Last saw it with my 10" Newt around 3 in the morning, eyepiece was an ES 14 82º giving 85x. To my eyes the pup is a green dot. The E+F stars in the trap were also easily seen that time. Also seen it with my f12 6" refractor with an ES 28 68º giving 64x. I think less mags is better. It reduces the glare of Sirius....seeing plays a big part and decent optics. I tried for a year with a 6" f8 Synta refractor but never really saw it, thought I did a few times but couldn't be sure.
I find Antares a bit harder than Sirius...finally got that one too.

Matt

[bigjoe]

Hi Matt.

Wonderful to hear that you bagged it in that low a power in the 10"- 85x wow; there's hope for all out there after all. Aperture obviously helps, but the seeing you had at 3am is quite often a lot better than most will stay up till.

That being said that's quite an achievement most will never realize in this hobby, so well done!:thumbsup:

PS: I still drool over that refractor image!

Cheers bigjoe.

[AG Hybrid]

Its actually not that difficult a split I think. Aperture really helps here to pull in the light of such a dim small object. Seeing is important, but I've never had much of a problem. Can't do it in my Achro but its no problem at all in the 12". Even on nights of average seeing I've seen it because - aperture. The best challenge is when that little white dot is hiding in a diffraction spike. That's turning the difficulty up to 11.

[Bombardon]

Lovely report here, Joe and all the comments from the 'Sirius B Team.' Congrats on a great achievement indeed. I'm afraid I have over the years only conquered the Antares' B Green Gem Challenge and finally spotted Rigel's feeble mate in the last 12 months and have tried - but obviously not enough - to separate the Pup but no success.
Here is a question from someone new to this brand of sky game: Do I need Joe's X560 (even my long abandoned feeble light gatherers with telrad support wont take me past about X300) or can I make it if John B can reach it with X292, skysurfer with X128 and Matt, who must have eyes like Stephen James O'Meara, with a staggering X65!? I have tried a home made bar on a 9mm with Barlow taking me to X300. I have even run every filter I can find past this great star, but nothing so far. BTW my best success with Antares B was in evening twilight and in steady Autumn air with my home figured 16"(and which truthfully was not a great glass). You have inspired me to wait for these magic moments and to keep trying. Nice pic of the shy critter, Marc. Long live the star splitters!

[bigjoe]

Great to hear this , as Iv'e never looked at Sirius in above 7" , though next time I will try in my 10 sct, as I thought the central obstruction might hamper my attempts.
So it seems aperture and seeing might be the keys here ? and not to worry too much about getting over 200x , unless using small apertures.

PS: I've heard of people rotating there tubes now and then because of the spikes, not so easy in the flex tube though, to see if the PUP is being masked, and maybe this is what happens to some observers!

Cheers bigjoe

[MortonH]

Supposedly it's possible to see it in an 80mm scope just now because the separation is quite large. I've tried a few times with the Tak over the last few weeks but no luck yet.

[bigjoe]

Great to hear from you Eugene-and yes I think Matt's eyes are like O'meara's -WOW!

Still I wouldn't bother with filters any more I think, as it's so faint.

Instead wait for those moments of great seeing after midnight if need be.

PS: I too will be going after Antares next- I've done it once some years back, and now will try again soon enough; it's a glorius double.

Cheers bigjoe.

[bigjoe]

Morton Hi

That Tak of your's is just made for this, so I would say it's just a question of seeing, altitude, and some mag here and nothing more.

Cheers bigjoe.

[MattT]

I doubt I have that good eyesight....Rigel is an easy split. They say it's the same distance as the pup is....doesn't seem like it. The pup is green and Antares companion is blue for me. Never seen colour in any nebula ever with my scopes though, only stars.

If I'm lucky I'll get the 10" out tonight and give it another shot.

[bigjoe]

Do so Matt, but I think your being modest and you do have a fantasic arsenal of equipment at your disposal.

Yes; to me the Pup is greenish and Antares has a greenish/blue companion to my eyes , and Rigel is an easy enough split.


PS: We need more of these types of discussions if, for nothing else, so as to expect what one will see, in what aperture etc.

Cheers bigjoe.

[MattT]

Hi Joe,
Wish granted...thus far. Taken a few minutes ago the 10" Orion Optics UK Newt with ES HR coma corrector and my all time favourite finder scope a Sharpstar 60mm ED f5.5 with a Pan 27 in the focuser....the weather forecast says cloud from 9pm til 1am...will hope its wrong.
Have mozzie coils waiting :D hate Summer observing due to mozzies...anyway will find out soon enough :)

Now I don't know if my spider has anything to do with it but I prefer the OOUK curved spider more than the 4 vane thing.

[bigjoe]

Know how it is Matt, got eaten alive by the mozzies last night after forgetting the Aerogard in my haste to set up for Sirius B. Oh well it was worth it in the end. Good luck with this- love the spider, ocular and all the sharpstars sound fantastic BTW.

Cheers bigjoe.

[Tinderboxsky]

I agree and am enjoying the conversation.

Using my Vixen ED103S, I find Rigel a straight forward split in most seeing conditions at 60-100X. Antares, is much more difficult and very dependent on good to excellent seeing conditions. I have had a number of clear splits using the Vixen at 150X. My best views of the double have been through my NA140SS at 320X in absolutely outstanding seeing conditions with a full moon only 20 deg away.

Am still trying for Sirius!!!

Cheers, Steve.

[Bombardon]

No success with Sirius tonight but conditions were very challenging: High cloud, impossible humidity, persistent mossies and to cap it all ABC in the background were playing very disturbing violin music. However, on a positive note, thanks to John B's suggestion I tried a 4" off centre hole on a plywood mask on the front of the scope and got a much clearer view of the Alpha Crucis binary and even managed Rigel's shy companion. Things are looking up :)

[bigjoe]

Thanks Steve

Looking forward to more. I myself nearly purchased the older version of that Vixen, the 140 NSS f I think it was then from AOS ; good as it was now it's much improved, and by all accounts a cracker on a vast array of objects, with its wide flat field and ample aperture Petzval design-The objectives and all made in Japan now, and the other refractor speaks for itself; still may get one, as I will be in the hunt for a large refractor soon enough.

Keep trying as your attitude and equipment are exemplary.

Cheers bigjoe.

[bigjoe]

Hello Eugene

Glad you've finally bagged Rigel, as I think seeing and not the scope has let you down here, as for some it's not considered a major challenge in most scopes.

Great suggestion from John B also, masking has obviously helped.

Looks also like you were facing a near impossible task with all that goings on.

Lets hope you have better conditions soon.

Cheers bigjoe.

[MattT]

Meanwhile back at the ranch....nothing happening here either. Glare city for Sirius. Thought I got a brief glimpse once...not enough. Conditions I'd rate at 5/10 really light blue sky and today was quite humid. Tried all sorts of eyepieces and went as far as a 5mm ortho with 2x barlow...480x :eyepop:.no good at all.
To quote an old song...One of those nights...

There is always next time.

Possibly less aperture would have given a better result :shrug: I've mostly had success in the early hours, which means Spring time.
Will try the 6" f12 another evening.

[bigjoe]

Yes Matt that's how it is with the PUP, you think it's there then it's not ; absolutely frustrating.

I'll wager though, that marvelous unobstructed (no diffraction spikes etc), long focal length well corrected refractor will be easier to do just this given the right conditions, as it seems you had Buckleys of doing this tonight in those conditions.

Cheers , goodluck, and hope to hear more of your reports soon.

bigjoe.

[The_bluester]

Rigel has always been a fairly easy split with my C925, so I think I should have a try at Sirius at the upcoming SVAC next month.

[MattT]

I forgot...I did a sketch...of sorts:D Not quite Alex Massey quality but this is as good as I get. This is in fact my first ever sketch....probably my last :lol:

Sirius is the big one round blob, the pup is just above. E is marked so the pup is about 4 o'clock. Just the briefest of looks on this. I marked a star red as thats what it looked like...no idea what it's name/number is.

I don't keep notes of what I've looked at either.

[bigjoe]

Good to hear you will do this also Paul.

With possibly the best type of SCT ever made, who some have compared to a Mewlon, because of its sharpness, contrast and longer focal length primary and coatings, I would expect you will have a great chance of cracking Sirius.

I think we would all hope to get a report from you, if you do or don't.

Cheers bigjoe.

[bigjoe]

Great idea Matt. I must remember to do just this next time the seeing will permit me to have another crack at Sirius.

bigjoe.

[Tropo-Bob]

I tried a range of magnifications up to 360x tonight with my ED Vixen 115. No luck again.
I have been trying with lots of different telescopes since 1970 but to no avail even though Sirius is almost directly overhead here.
I have read that it is more difficult to see in humid climates, so I guess that this adds to the difficulty.

[Bombardon]

This is a direct quote from the Royal Canadian Astronomical Society website that I thought we Pup Hunters would find useful. The 'Superior Power," which I emphasized in red is obviously a reference to BigJoe:lol:


Seeing the star

There are several things you can do to increase your chances of success:


be familiar with the orientation (http://rasc.ca/) of Sirius B relative to Sirius A in your optical system - this will tell you where to look
practice on a double star with a similar separation, but less dramatic contrast in brightness between the members - this will give you a sense of the angular separation to expect. Try practising on Rigel (β Orionis) or Almach (γ Andromedae)
the customary minimum aperture is 200mm, but some have used 100mm - can you detect it with a smaller aperture?



use a magnification of 200x-300x, and try to place the primary star (Sirius A) on the edge of or just out of the field of view



make a semicircular filter out of plastic (use a violet, or blue, or green. or red, or brown, or grey [neutral density] colour), and place it either: a) in a regular filter cell; or b) at the field stop or other accessible internal position within the eyepiece (easiest in a modular eyepiece). This half-field filter will diminish the brightness of Sirius A, while leaving the brightness of Sirius B unaffected. As an alternative, you could make a half-field occulting mask and install and use it like the filter (as is demonstrated in this video (https://www.youtube.com/watch?v=y5R2nZlAWq0)). If you are unsure about modifying your equipment, do not attempt taking apart an eyepiece for b) - try a) instead



make a hexagonal diagphram. The central opening should have the shape of a hexagon, and be as large as the aperture will allow. According to Duplessis and Souplet (http://www.cielnoir.net/Observation/Cielmois/Doc/Sirius-B.pdf), the angles of the hexagonal diagphram "canalize" the brightness of the primary into "feathers", enhancing the contrast in the zones between those features. Simply position the mask so that an inter-feather zone is where the companion star should be to enhance your chances of observing it. The great E.E. Barnard (a RASC member (http://adsabs.harvard.edu/abs/1923JRASC..17...97P) - also see here (http://adsabs.harvard.edu/abs/1924JRASC..18..309P)) published a description and drawings (http://adsabs.harvard.edu/abs/1909AN....182R..13B) of this most useful of DIY mods
owners of go-to telescopes (or traditional equatorial or alt-az telescopes with drives) may wish to use the drift method to find the position of Sirius B. It's simple - turn off your drive! Since the companion is fairly close to due east of the bright primary it will "follow" behind it quite closely. So as Sirius A drifts away from the centre of your FOV, Sirius B will approach it. By a rough estimate, Sirius B trails Sirius A by 2/3s of a second (of time)



allow sufficient cool-down time for your OTA, and ensure it is well-collimated



try to pick a calm night of good seeing (fortunately, our winter-wonderland of the frozen north does offer these). It is worth trying in less than optimal conditions, but in such a case remember to choose an observing location shielded from the wind. It is worth attempting the observation from light-polluted areas, provided the full moon isn't near the Sirius system



dress properly for the weather



be patient, and rest your eyes! And, to paraphrase William Herschel, "it should be remembered, that when an object is once discovered by a superior power, an inferior one will suffice to see it afterwards" (RSPT 90, 1800, 29 (http://rstl.royalsocietypublishing.org/content/90/49.full.pdf+html?sid=16746512-e74b-408e-9f52-9f46461c99d6)). You won't need an 18.5" Clark to detect Sirius B, and once you see it, you'll be able to find it again with comparative ease!

[bigjoe]

Thank you Eugene I love this!

And yes I'm still trying to be HUMBLE.

YES...... It's so hard being a role model now.......so very hard:P

Seriously though what great tips! Practised on Rigel first- Yes I did and high power -yes ; East as I said , and let it drift as Pup will follow -yes etc.

And the diagphram and mask- what a tip; Im using them next time!

Just got home and to bed -More on this morrow

Cheers bigjoe.

[Tropo-Bob]

Thanks guys for all the hints on how to find Sirius B. I have done the prelude of looking at viewing Rigel first to have an idea of the distance. So tonight, I am going to use my C8 Edge and see if aperture does the trick. Instead of Rigel, I intend to use Delta Gemini as my comparison star (Mags 3.6, 8.2, separation 5.8"). At least the secondaries of both stat are about the same brightness, even if Sirius itself is some 100 times brighter than Delta Gemini. (Delta G is near the Eskimo Nebular, so I will check that also.)

Here's hoping that tonight's the night to see a pup!

[bigjoe]

How on Earth do you dig all this juicy information up Eugene!! Maybe it is you who are the superior power and not myself!!!

Still I feel it is our duty to enlighten others to this nice and almost forgotten pastime of splitting doubles.

SIRIUSly though ; let's look at just some of what is required:

1: SEEING- Must be excellent.

2: ALTITUDE - Well above the horizon in
most instances.

3: APERTURE-100mm+Cooled and well collimated.

4: POWER- The use of it is necessary- 200x + may be needed.

5: USE A MASK- Hex , may be necessary.

6: ORIENTATION- Is your diagonal/scope displaying an upright E/W view; If not adjust accordingly.

7: PRACTISE on Rigel say - Bright, with similar separation.

8: DRIFTING- Let Sirius A drift past the field stop , and disappear, as B will surely follow.

9: WARM CLOTHING , and stool if necessary.

10: PATIENCE- and lots of it -It could take many attempts!

These are just some things required to have a chance at Sirius and a lot of other tough doubles- So goodluck.

Hoping this all helps.

Cheers bigjoe.

[bigjoe]

I've heard this before also too Tropo-Bob.

This makes it all the more harder for you , even though you have outstanding optics there:thumbsup:; so good luck and keep perservering -you'll get it sooner or later- I have no doubt with your doggedness.

[Bombardon]

:lol::rofl:Joe,
However, for Joe and Double Camp Followers I found out that the excellent "Double and Mulitple Stars," by James Mullaney, is available on Kindle for a free trial period. (not to be confused with a sample few chapters); Some great chapters on viewing, equipment and anecdotes, measuring techniques, the great double hunters, plus two large and detailed sections on the best doubles. No commitment to buy.
Is this Double Star Festival never to end? Let's hope not! Eugene

[Bombardon]

In case the time poor star splitter missed it in a previous post I grabbed this link from the last on Sirius and is a great article by the famous William Herschel on his viewing techniques, with a lot on optics and light.You will need time and a cloudy night :eyepop: to fully absorb this. PS: you can see I am getting viewers' cabin fever:sadeyes:

http://rstl.royalsocietypublishing.org/content/90/49.full.pdf#page=1&view=FitH

[Tropo-Bob]

Success is sweet, I have seen the Pup!:eyepop:

Using a C8Edge & a Tak 6mm Ortho EP, I found it, a bit further from Sirius A than I was expecting. Using Delta Gemini as a guide worked well. Delta G is like a fainter Rigel, but the secondary's magnitude is similar to the Pup so gave me a much better idea of what to look for than does Rigel.

Thanks guys for all your tips! :thanx:

[bigjoe]

Looks good Eugene!

Also of course there's the Cambridge Double Star Atlas, authored by Bruce MacEvoy and Wil Tirion (FEB 2016) of which James Mullaney contributed so much to the original book and concept.

I should mention that earlier, USE OF SHORTHAND is used in describing the position of a component in a double star system; the Cardinal directions are used : North , South , West (preceding) and East (following) , as is the case with the "PUP"

This can also be broken down to north preceding etc, all of which can prove very helpful, if you want to use the field stop method etc.

But once again one MUST be careful with your orientation , VIZ : Is your image upright or inverted, or reversed East/West as in a di-electric diagonal etc.

Hope this will be of help to all interested .

bigjoe.

[Tinderboxsky]

Indeed, lets hope not. Just to keep things bubbling along I have posted a new thread putting it out there to see if anyone is contributing to Sissy Haas’ Uneven Double Star Project.

Well done Bob in resolving the Pup. :) I am still completely cloud bound. :sadeyes:

Steve.

[bigjoe]

Well done Bob, it was once considered quite an achievement and still is in my opinion.

1: "a bit further from Sirius A than I was expecting"- is exactly what I thought also ; so we two concur here
.
2: You used a warm up PRACTICE STAR -WELL DONE BOB- IT ALL PAID OFF!

3: That Edge of yours with it's light grasp, would have kept the Pup nicely in focus, and see-able even towards the field stop-A great scope and EP, by all accounts for this- Congratulations on an achievement also.

bigjoe

[bigjoe]

Thanks for this also Eugene -you keep outdoing yourself!!

PS: If I don't fall asleep -I 'll attempt a reading.

Cheers bigjoe.

[bigjoe]

Thanks once again for your contribution Steve!

I'll check it out also, and lets see if we can keep things moving in this doubles pursuit!

bigjoe.

[AG Hybrid]

Well spotted it again tonight. Had to wait for "sucker holes" in the clouds so I can get some clear sky for Sirius.

Here was my log of events:
*Removed cover off my 12" dob.
*Rolled it out of a rather warm garage.
*Extended the OTA to full length.
*Checked collimation and made adjustments accordingly.
*Selected a 14 min Delos. This gives about 106x magnification and an exit pupil of about 3.3 mm
*Turned on the rear fan which both cools the mirror and due to selective baffling pushes air over the primary effectively eliminating the boundary layer.
*Pointed the scope at a random star that was near where the OTA was pointing and brought it to focus.
*Waited about 2-3 min for a hole in the clouds to open up around Sirius.
*Moved Sirius to the center of the field of view in the eyepiece.
*Spotted Sirius B immediately at about 11 o'clock just above a diffraction spike located at 10 o'clock from Sirius.

This was all done in the space of about 10 minutes. Sometimes folks you just need light gathering power and resolving power. With the clouds moving fast overhead obviously seeing was pretty average too.

[Tropo-Bob]

Maybe those fans do work, I have owned both a 12.5" Dob and later a 12" Dob but never was able to split Sirius. It was closer then off course. However, like most things, once done, it becomes easier.

It might be wise to recheck the exit pupil calculations... I suspect it is closer to 2.8mm.

[AG Hybrid]

Too true. My mistake. Probably should not have mentioned it anyway as a main factor as switching to a XW10 brings magnification to about 152x with a 2mm exit pupil only made the split easier. Image brightness and surface brightness matters.

[The_bluester]

Being a star party, if I have a go and succeed I will get someone else to have a crack as well, just to be sure.

[Allan]

Sirius is one of those targets I check every time I go out. I use it as a gauge for the sky conditions. I think it was Matt who said it, but once you've seen the pup you can't help but to see it every time, as long as the seeing co-operates.

Seeing is the most important factor, and it helps that it passes through zenith here in Oz. Aperture isn't so important, but quality is. The best view I've had of the pup was in my 5" Tak. I can see it ok in my 4" NP101, but the few times I've tried in my TV85 I couldn't see it. But I haven't been able to see the F star in the trap with the TV85 yet either.

The split is large and the pup is fairly bright at mag 8. It's all about how much scatter Sirius is throwing up in your telescope/eyepiece combination, that will determine how easy the pup is to see.

[bigjoe]

I hope you can, so we can all compare notes on what is needed.

Goodluck.

bigjoe.

[bigjoe]

Hello Allen, great to have your input.

There's been discussion on minimum aperture; do you think that maybe you and all here, may have established that around 100mm could well be the minimum aperture required here in Sydney at least , given that Sirius is also so high in the sky, and a lot easier than some will face.

Seeing of course , but not so much it seems if you have a good 12" like Adrian , you stand a better chance, especially if you 've done it before; this definitely seems to help in the search again .

Scattering also is an issue at the EP , but having high quality optics especially APO's is also an advantage it also appears.

Cheers bigjoe.

[bigjoe]

Hello Adrian .

Yes- it now appears to be established that aperture is a big advantage in all the reports coming in; though it also appears that a nice refractor in the 100mm range will do it also, but with difficulty: VIZ Allan ; but not yet for Morton in his superb Tak.

The cooling fans also would have been a must with such a large mirror - 12" about the maximum limit of what some seasoned doubles observers say is required, so as not to be so affected by average seeing conditions, which is less of an issue with smaller much apertures.

You make it sound so easy , but it's NOT and you are a seasoned observer with vast experience, and 10 O'clock is where it should be East -following; so well done once in a remarkable time frame, and through sucker holes!!!

Cheers bigjoe.

[Allan]

Hey bigjoe. There are numerous reports of seeing it in good quality 4" refractors. I think the 3" size might be stretching the friendship, but it is up to us Southern Hemisphere observers to try. It's clear with low humidity right now, so I'll give it another go tonight.

As Adrian has posted, a 12" dob is a good scope to use and the extra aperture makes it easier. What I found side by side with my 12" dob and 5" refractor was that Sirius was a little tighter, with less flairing and scatter in the refractor, so the split was a little cleaner, and more aesthetically pleasing.

[Tropo-Bob]

Last night, as previously mentioned, I viewed the Pup with my C8.

I also tried to find it in my Orion 80mm Triplet, but probably with too low a magnification. However, I had been inspired with a thread on Cloudy Nights, which mentioned finding the Pup with 80mm scopes only using about 70x.

Well I tried at 80x and failed. The 80mm struggled a little even with the secondary of my test star, Delta Gemini (also at 80x). Yes, I could see it but had it look carefully, as it was faint. Whereas, the C8 immediately and clearly showed the secondary of Delta with a 30mm EP. (about 67x).

[AG Hybrid]

Gotta watch out with those Americans. Some of those observing reports are coming from people who are observing 2-3 KM above sea level. From my home in Sydney I'm observing at about 50m.

[bigjoe]

Hello Allan.

We would all be happy to hear if you are able to do this-let alone attempt this in such a small, but superb instrument.

You'll have the advantage of a nice fat Airy Disk and fainter diffraction rings to help mitigate speckling interference with the "PUP" though, in that refractor, and no Central Obstruction to deal with.


Darkening the sky background with higher magnification will help with separation and limiting magnification naturally, and the small exit pupil may help you if the seeing is not perfect.

So let's see if you can do it!!

bigjoe.

[bigjoe]

Exactly Adrian -Another advantage, elevation above sea level.

We're lucky though Sirius- it's almost above our heads!

bigjoe.

[bigjoe]

Aperture once again it seems Bob; a clear advantage all things being equal.

I'm finding also that the trick of going back and forward between direct and averted vision helps dramatically also- until the companion is there with direct vision, and more power to help with limiting magnitude could do the trick with such a small aperture.

PS: And that 80mm Orion triplet got a great review once by Dr Clay Sherrod , so we know it's good.

bigjoe.

[AG Hybrid]

So... as an experiment I followed the advice that has been given so far in this thread and really gave a proper go.

I can now say I did it. It took me to the very limit of my skill and experience but I DID IT! I spotted the Pup for the first time in my $400 Explore Scientific AR102.

It took some experimentation especially deciding which view was best between using a Baader Semo-Apo filter or no filter. The CA was overwhelming on Sirius so I used the filter at the expense of a little bit of light lost.
I put my 2x barlow in front of my diagonal as to produce more magnification as it would if it were behind the diagonal and then putting the eyepiece straight into the barlow.
I then used a Baader Hyperion Zoom to gauge the best magnification and exit pupil the atmosphere would support. Atmospheric seeing was decent tonight as I observed Jupiter prior, as it rose. I was able to see four bands on Jupiter which was pretty good for the AR102 especially considering how low it was in the sky.

The advise to use Rigel in Orion as a benchmark and test object is a very wise idea. It gave me an idea what I was in for and I noted that CA was overwhelming too. Had to use the filter and glad that I did because it was the first time I saw Rigel B in the AR102 as well. While still lots of CA the little white dot was there with direct vision. Nice.

So, to Sirius. This was hard. Very hard. As I mentioned earlier the CA caused by Sirius was overwhelming at the magnification I was using. Would have been well over 200x. I would approximate that over 40% of the field was blue haze. The filter was necessary. It did a good job, the CA was less then 10% of the field now. Still rather intense around the Sirius itself, just contained. Using the zoom I gauged the best magnification to find that sweet spot between image brightness and contrast. This took some time. I also was using an alt azimuth mount which means Sirius was always on the move and moving fast. It was only a for a few seconds in the center of the field where the best field correction is and my windows of best observing were constantly being reset. But, I've never owned a tracking mount so it was second nature to me. Muscle memory even.

While watching Sirius floating from top left to bottom right going through the field it appeared as it floated through the center of the field. For about 4 seconds the little white dot appeared on the outer most diffraction ring. It looked to be about 2 o'clock. I'm certain it was a positive result as I had spent the last 30 min noting false-positives caused by eye floaters. I don't have many but they are really obvious when they do appear at that tiny exit pupil. I knew exactly how the floaters looked and how the moved and acted. That little white dot I saw stuck right by Sirius as it zoomed through the field of view. The eye floater moved around and rarely in a straight line.

Pretty pleased with that as a whole. Although next time I'm just going to roll out the 12" ;)

[skysurfer]

Yesterday night tried again, from South Africa, seeing was rather still with ED110 + WO dielectric diagonal + Vixen LV6 (128x), but no pup.
Tonight another try.

In Holland many people claim to see the Pup despite Sirius never comes higher than 21 degrees above the horizon. But I disagree.
https://translate.google.com/translate?sl=nl&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fwww.astroforum.nl%2F showthread.php%2F162495-Eindelijk-Sirius-B%21%3Fhighlight%3Dsirius&edit-text=


11. As few glass-air transitions as possible.

[Tropo-Bob]

Adrian, that is a huge achievement if you found it in such a small scope with CA issues as well. However,I am confused about your use of the clock for directions. The Pup should trail Sirius A in an undriven scope. If I am using the clock in the same manner as yourself, my observation was that it was at about at 7 o'clock position. Given that you saw it in your 12" reflector at the 11 o'clock position, I thought our observations were in agreement when you swap the up and down positions between at refractor and a reflector. (Left and right being unchanged of course).
However, you say that you saw it at 2o'clock in the refractor.
I am not saying that you did not see it, but was there anything else going on to confuse the directions; like did you have the star diagonal twisted to the side or something?

[AG Hybrid]

Actually your right. I was thinking about another double that I split when I typed that. It was trailing at about 10 O'clock. But damn it was hard. Also to remember that the location of the Pup changes drastically between 7:30 PM and 10:30 PM at the moment. It looks like more than 90 degrees. I was observing for more than 3 hours last night and I looked at Sirius every hour. It could have been a false ID now that I think deeper about it. It was so difficult.

[bigjoe]

Thanks for NO: 11 skysurfer I'm sure we'll need to add even more tips!

And one has to wonder how they can see Sirius B in such a low altitude with probably a boiling image through the EP!!

Cheers bigjoe.

[bigjoe]

This just highlights the extreme difficulty one can face just to get yourself set up for this task: am I using an upright diagonal : is it reversed East/West : in what direction is my mount/ scope pointed from North as position angle is taken from an imaginary line on the celestial sphere due North , increasing North to East in a clockwise direction - East following here as in Sirius B being roughly around 90 degrees or more position angle: right magnification and resolving exit pupil etc, etc.

bigjoe

[AG Hybrid]

Sure this. Or big newt. :P

[bigjoe]

The use of a zoom and filters are great ideas Adrian, that should be number 12/13 on the useful tips list-helping to find the right mag and exit pupil for the seeing, and task at hand- good ones !

Morton has of yet not been able to do it in his 100mm tak either from last accounts, so it must be very difficult at this aperture but was easy for you in the 12"!

Who knows for sure-More attempts I guess just to make sure.

bigjoe.

[MattT]

I'm going to add:

#12. Use a long focal length Achro.

I tried again on Saturday night and got the Pup in the 10" no problems. The E+F stars in the Trap were visible too.

So onto the 70mm f13 Achro. Yep this 70mm is well in the Conrady scale for CA at about 4.5. Sirius was a white star, shown as an Airy disc with a couple of diffraction rings, dimmer and a lot less scatter than the 10".
I got a result that was surprising to me but more on that later as I need to try it again on another night.

In the meantime read this article by Neil English...love him or otherwise :lol:

http://www.cloudynights.com/page/articles/cat/articles/stranger-than-fiction-r2452

This is turning into an epic thread.

[MortonH]

I tried several times again last night but no luck. Dozens of false positives caused by speckling or tiny reflections that look like it. My problem is most likely that from home I can only see Sirius from my west-facing balcony overlooking a busy road. Since it's been baking in the sun all day the local heat signature, plus the traffic, disrupts the seeing.

[bigjoe]

I'm a Neil English fan -so glad you brought this up.

My favourite scope type ever is a long f/ratio Refractor. I can well remember the images Of Mars etc in my now sold 4" F/15 Unitron -Never seen better since, except maybe Mars one night in May back in a 7" Mak; it was that good.

Just had a quick read, and he talks about the greater DOF, less spherical aberration, height above ground of the objective , and greater encircled energy per given strehl, all adding to a STEADIER image than say an ED doublet, but less so for a triplet and he says contributing to less eyeball strain in these long F/ratios.

HOW GOOD THIS WILL BE FOR OBSERVING DOUBLES ;WE MAY SOON FIND OUT FROM YOU MATT!

Wishing you goodluck with this!

bigjoe.

[bigjoe]

Just for a lark I tried a 30min look again at midnight last night, in a 10 SCT , and 13mm T6 nagler-no luck at all either!!

bigjoe
.

[bigjoe]

Had a quick read last night .It was interesting, and logical at the time I'd imagine, to use star brightness to calculate stellar distances. His thoughts on the effects of central obstruction , and aperture on resolution and the way he would just create the formula needed to solve a particular problem - His construction of huge scopes and double star, and DSO observations -all a great read.
He would have been a fascinating person, like Halley to have at the dinner table- Musician : writer of symphonies that are still played :discoverer of infra-red radiation, and discoverer of Uranus etc ,etc-PHEW!!

bigjoe.

[bigjoe]

Summary of some of the things you may need to do to see any difficult double, including mainly the PUP here.

1: SEEING- Must be excellent.

2: ALTITUDE - Well above the horizon in
most instances.

3: APERTURE-100mm+Cooled and well collimated, though probably no more than 12" due to the affects of seeing on large obstructed scopes.

4: POWER- The use of it is necessary- helps darken sky background and with limiting magnitude ;200x + may be needed.

5: USE A MASK- Hex , may be necessary.

6: ORIENTATION- Is your diagonal/scope displaying an upright E/W view; If not adjust accordingly.

7: PRACTISE on Rigel say - Bright, with similar separation. Know what a separation of 10" will look like in your go to EP -VIZ- Know your field.

8: DRIFTING- Let Sirius A drift past the field stop , and disappear, as B will surely follow.

9: WARM CLOTHING , and stool if necessary.

10: PATIENCE- and lots of it -It could take many attempts!

11:LESS GLASS-Use of EP with fewer elements 4/5 max to increase contrast and detection may be of help.

12:AVERTED AND DIRECT VISION-Go back and forth between direct and averted vision until the companion is held in direct view.

13: ZOOM EP - Use of a good marked zoom EP, to find the optimum power for the seeing and filters if necessary.

14:HIGHLY ACCURATE FOCUS-TOGETHER WITH A NICE FLAT FIELD, FREE OF CURVATURE -this is a must also , and you may have to re-focus often.

15:VERY STABLE MOUNT-Absolutely no wobbles!

16:VIEWING AT TWILIGHT- Can reduce the glare of Sirius A -and this goes for other bright primary doubles as well!

No doubt more things will be needed to be added as we go along ; perhaps long focal length small aperture achromatic refractors as Matt has will be of great use -reports due soon!

bigjoe.

[AG Hybrid]

Eyepieces with green writing on the side. The brighter the better.

Observe from 3 km above sea level.

Observe in winter. The skies are darker and nights are longer.

Eat lots of carrots.

[bigjoe]

Yes Adrian- "Eat lots of carrots":P, should have been No.1
on the list; our mums were right weren't they!

And yes EP's with bright green writing, usually are the best

Observe in Winter crisp skies -yes.

And elevation above sea level, I guess has got to go on the list, though perhaps not some of the others!!;)

bigjoe.

[Tinderboxsky]

In my opinion, accurate focusing is essential and should be added to the list. I have a home made, soft touch 17:1 fine focus on each of my scopes. It helps to give very accurate focusing.

Steve.

[bigjoe]

Will do this Steve.

ASAP Fine soft touch focusing 17:1 that is good!!!

And I think also Steve, your suggestion elsewhere of a "rock steady mount".

Cheers bigjoe.

[skysurfer]

It is simple: the Pup is on a PA of about 90 degrees (i.e. East) of Sirius A, which means that it is moving 'after' A with a steady scope, regardless of orientation or diagonals.
A trick is moving the star to the very edge of the field and let A disappear and then B should reveal briefly.
I'll try on the first night with decent seeing.

[skysurfer]

No, these eyepieces have lots of glass-air transitions which means more scattering. Nice for widefield and many other uses, but not for this critical observation. Use eyepieces with a very simple design like Plössl or orthoscopics.

In winter the skies are not darker, unless you observe from high latitudes (> 50 deg, e.g. N. Europe or Canada).
In the southern winter, the sky is even lighter because the brightest parts of the Milky Way are high in the sky. And Sirius is low if visible at all.

[bigjoe]

Exactly skysurfer -as I've stated in No.8: And also EAST 90 deg stated earlier; it should follow after letting Sirius A drift past the field stop.
Cheers and thanks for your input.

PS: Let us know how you are going with this.

bigjoe.

[AG Hybrid]

LOL. Those jokes went straight over your head. Its nigh impossible to observe at over 3km in Australia. Sirius is also a summer object.

Also, Delos and Pentax eyepieces are perfectly acceptable for double star viewing. If you stareing for long periods at tiny objects comfort at the eyepiece is also import.

[bigjoe]

Ha, Ha-Their Plossls are good for this though , not so much their widefields it seems and your generally right as they are not truly orthoscopic ; but Adrian does not seem to mind if the glass used and construction has very low scatter it appears and high quality , as a poorly made plossl could indeed be much worse!
PS: I still use the best of their widefields though at times!

Got this down as NO:11- LESS GLASS.

bigjoe.

[Kunama]

:lol::lol:
The closest you can get to it is 2745m above sea level, and you'd be freezing your RRRRs off.

[bigjoe]

Exactly also Matt.

Some people you can attempt humour at ; others not it seems.

Cheers and thanks for your welcome input.
'
bigjoe.

[bigjoe]

Thought I would adjust the title, to reflect all the wonderful advice given here by many members, that would be of use , not just for Sirius but double star observing and reporting generally as well.

As usual all input most welcome for the benefit of all interested.

bigjoe.

[skysurfer]

But Sirius is a special case, as the magnitude difference is a full 10 magnitudes (i.e. a factor 10000), unlike 'normal' double stars like Alpha Centauri or Alpha Crucis which are even visible in full daylight with a small scope.

[bigjoe]

Skysurfer- it's all our MEMBERS ADVICE , most of it will come in handy for ALL other double stars in general.

EG:KNOW YOUR FIELD , PRACTISE, USE COMFORTABLE STOOL,WEAR WARM CLOTHING, APERTURE, USE OF ZOOM, DRIFTING ETC, ETC.
HOPE THIS HELPS

bigjoe.

[Bombardon]

Hello all Puppy lovers. Last night did not bode well for me, as even the Rigel wrestle failed:sadeyes: However, I did enjoy the sparkling(!) Jupiter as I warmed up(cooled down) and found John B's mask really steadied the image. I spent most of the night on Corvus as I was keen to visit some old faint fuzzy friends, The Antennae etc, and will report in due course. To keep 'you know who' happy I got into some fine doubles as well and was most impressed with the lead in doubles to the Sombrero.
Tonight looks not bad so far so I had better plug in my super dooper humidity extractor soon. :) Just keep bowling me over with the serious Sirius attacks.
Eugene

[bigjoe]

Hello Eugene - at least one PUPPY lover hear.

Strangely enough I was almost doing the same as yourself last night!!
VIZ: Viewing the GRS its hollow, and some other details there and was just about to go over to the Sombrero, and the wonderful IZAR before it just got too late!!

Well possibly tonight , and another go at the PUP in my 10" SCT but I'm going to see my brother who's just come back from Las Vegas were he mostly lives, so I'll have to wait and see.

PS: Hopefully Matt and some others can report on what they have seen of Sirius in their smallish Refractors!

Cheers bigjoe.

[bigjoe]

Just added another great tip for Sirius and some other bright doubles courtesy of John Hothersall!

Look at his fabulous image of Sirius A and B in another thread.

PS: you will find this in the Solar System Section.

bigjoe.

[75BC]

I have nothing constructive to add but just wanted to say how much I’m enjoying this thread.

I’m new to observing these types of objects (doubles and multiples) and there have been some great tips n tricks here.

For those with less experience such as myself this will be great resource to go back to. :thumbsup:

[Bombardon]

Did I mention Joe, that if you have street lights a cowl or hood, such as those monks with the hairy legs sported in days of yore, can improve spotting really faint companions. ;-))

[bigjoe]

Brendon; you have some terrific gear there! Which I have no doubt will do the trick on Sirius, and some other very faint or close doubles when the opportunity arises for you.

So goodluck; follow all the advice of our well respected members here, and we will be adding even more tips soon enough - and welcome also!

bigjoe.

[bigjoe]

That's a great tip also Eugene!
No need for any modesty; it has to go in as a legitimate tip as good as the others! Well done once again.

bigjoe.

[bigjoe]

A SUMMARY OF DOUBLE STAR OBSERVING TIPS SO FAR
- VIZ SIRIUS:

1: SEEING - Must be excellent.

2: ALTITUDE - Well above the horizon in
most instances.

3: APERTURE - 100mm+, Cooled and well collimated, though probably no more than 12" due to the affects of seeing on large obstructed scopes; though it now appears certain, that even a 70mm achromatic refractor of long focal length can result in DETECTION!

4: POWER - The use of it is necessary - Helps darken sky background, and with limiting magnitude ; 200x + may be needed.

5: USE A MASK - Hex , may be necessary.

6: ORIENTATION - Is your diagonal/scope displaying an upright E/W view; If not adjust accordingly.

7: PRACTISE on Rigel say - Bright, with similar separation. Know what a separation of 10" will look like in your go - to EP - VIZ - Know your field.

8: DRIFTING - Let Sirius A drift past the field stop , and disappear, as B will surely follow.

9: WARM CLOTHING , and stool if necessary.

10: PATIENCE - and lots of it - It could take many attempts!

11: LESS GLASS - Use of EP with fewer elements 4/5 max to increase contrast and detection, may be of help.

12:AVERTED AND DIRECT VISION - Go back and forth between direct and averted vision, until the companion is held in direct view.

13: ZOOM EP - Use of a good marked zoom EP, to find the optimum power for the seeing and filters if necessary.

14:HIGHLY ACCURATE FOCUS - TOGETHER WITH A NICE FLAT FIELD, FREE OF CURVATURE - this is a must also , and you may have to re-focus often.

15:VERY STABLE MOUNT - Absolutely no wobbles!

16:VIEWING AT TWILIGHT - Can reduce the glare of Sirius A - and this goes for other bright primary doubles as well!

17: HOOD or COWL; this WILL help if streetlights or other bright light sources are a nuisance -- I rarely observe without one in any case!

bigjoe.

[MattT]

So now I have to dress like a Monk to spot the Pup?....Out goes the warm clothing..... which I have never done for the Pup, for obvious reasons :D

OK so I'm going to give it another go tonight and on the Gaunt is the 6" f12 with 70mm f13 piggybacked.

Sort of last chance for me as night work starts at the end of next week :sadeyes:

Hope to do a report later on...maybe me second ever sketch :question:

Ahh... bigjoe has added a list while I was typing away.....not ay all convinced about the Aperture size, specially down South as we are...will see.

[bigjoe]

Ha! Hope it doesn't get too hot and sweaty under the hood Matt!
You would probably look a right sight to any passer-by dressed as a Monk at the EP, but it can be a very solitary pastime....so maybe a good choice of outfit ;).

PS: Hope you can do a report before work sets in!

Cheers bigjoe.

[bigjoe]

I too Matt am not 100% convinced of the minimum aperture needed just yet, however it is on the list tentatively, as the reports so far in the 80/85mm class have proven fruitless!

So maybe it is up to yourself Matt; or someone else with similar experience, honesty and integrity with the sub 100mm class - So let's see then!

bigjoe.

[MattT]

Here are sky conditions over Mexico....sorry Melbourne at 8pm Thursday night. Should clear up later on I hope, still might get an viewing in before too long.

At this time of the year Sirius appears over the top of my neighbours Gum tree....as does so much other great stuff like M 104 later on....I wanna move to the country.

[AG Hybrid]

You don't need big aperture. It just makes it a cake walk. Well... as long as seeing isn't bad.

[MattT]

Well that was quick. The 6" f12 frac and a 27 Pan followed by an ES 28 68 shows the Pup without question. The tracking was playing up which didn't help...most likely I have forgotten how to balance the mount after using the 10" Newt so often...a hard life :lol2:

So the 70mm....A fleeting few sightings of the pup sitting in' between the first and second diffraction rings with a 6mm Ortho. Much the same as the other night with this. I'm surprised to see the Pup at all really with 70mm.My first night with the 70mm showed the pup inbetween the first and second rings with its own pair of diffraction rings... Kind of interesting watching the conditions change around Sirius...great one moment...a second later looking like a big ball of hair :eyepop: 70mm in the right conditions is doable,I reckon, but getting to the limit...luckily I have an 80mm f7.5 frac...and a 90mm f11 frac....could try the 50mm f12 :question:
It ain't over til it's over...

There is always Spring at 3 in the morning :D

[bigjoe]

Ha - This is just fantastic Matt, with a 6mm Ortho :thumbsup:; however I don't know weather to put 70mm down as the minimum recommended aperture, just yet!- I really do not know.

"It ain't over til it's over...".... Too true Matt - Maybe the 90mm will have to be recommend as the minimum that is, well easy enough, as it was not done in a TV85; but let's see !

PS: Can not wait till you try the 90mm at f/11; that could be in the easy enough class!! Question is ..Will you have enough time?

bigjoe.

[bigjoe]

Too true Adrian; but let's see how low we can go with ease - 90mm perhaps?

bigjoe.

[MattT]

I should add that the Pup is defiantly there in the 70mm just not a clean split. Think it's called 'detection' for the real observers :)

[bigjoe]

Great that you got detection and were almost able to get a clean split with only 70mm Matt!

However Squashed, Figure Eights, and Kissing Doubles are not considered a clean split - at least we need a hairline split; some black between the stars.

This could still happen though, at that aperture, but the seeing would need to be extraordinary!

Maybe this could happen at 90mm, but it was difficult even in a TV 101!
And as usual; the more reports on this the better!

bigjoe.

[Tropo-Bob]

Matt, can U tell us what magnification and EP were you using? Also, a little more about your 70mm scope (brand & focal length). Were U using a driven EQ mount to track Sirius?

[MattT]

Hi Bob,
The 70mm is a Skywatcher 70x900 so a focal length of f13 or close to. I think I stated earlier that there is no visible CA in this scope. Sirius did show up with the slightest purple haze out of focus all of which disappeared when in focus. Eyepiece for this is a UOVT 6mm which gives 150x (University Optics Volcano Top) I did try a 19mm Panoptic with a 3x ES focal extender
(Powermate)...there was no difference in the image.
I could see 2-3 diffraction rings around the Star which I think means that was too much mag for the conditions, as nice a sight as it was. Didn't think to try some other longer FL eyepieces, next time.
Used two mounts and EQ3 with tracking which is a great match for the 70mm and also my old pillow block EQ which also has tracking.

[AG Hybrid]

Well done Matt.

[Tropo-Bob]

Matt, that's amazing that you saw the Pup with a 70mm scope. I am gobsmacked!!! I was pleased to finally find it in an 8" and thought I had done well.

Big Joe, maybe your list needs to state a minimum aperture for initial detection, and perhaps a minimum aperture that the Pup can be seen by experienced observers who are already familiar with the double.

[bigjoe]

Amazingly so Bob !! As it was not seen in a TV85 in good conditions, with a very experienced observer !! So the long focal length with the steadier image it seems, and good optics, seeing, plus the observers visual acuity, have all helped here in this very modest aperture refractor; so well done Matt:thumbsup: - those long focal length refractors are something else when it comes to doubles: I'm sure of it!

PS: And it seems no real need for an Apo!

bigjoe.

[bigjoe]

AMMENDED SUMMARY OF DOUBLE STAR OBSERVING TIPS SO FAR
- VIZ SIRIUS:

1: SEEING - Must be excellent.

2: ALTITUDE - Well above the horizon in
most instances.

3: APERTURE - 100mm+, Cooled and well collimated, though probably no more than 12" due to the affects of seeing on large obstructed scopes; though it now appears certain, that even a 70mm achromatic refractor of long focal length can result in DETECTION!

4: POWER - The use of it is necessary - Helps darken sky background, and with limiting magnitude ; 200x + may be needed.

5: USE A MASK - Hex , may be necessary.

6: ORIENTATION - Is your diagonal/scope displaying an upright E/W view; If not adjust accordingly.

7: PRACTISE on Rigel say - Bright, with similar separation. Know what a separation of 10" will look like in your go - to EP - VIZ - Know your field.

8: DRIFTING - Let Sirius A drift past the field stop , and disappear, as B will surely follow.

9: WARM CLOTHING , and stool if necessary.

10: PATIENCE - and lots of it - It could take many attempts!

11: LESS GLASS - Use of EP with fewer elements 4/5 max to increase contrast and detection, may be of help.

12:AVERTED AND DIRECT VISION - Go back and forth between direct and averted vision, until the companion is held in direct view.

13: ZOOM EP - Use of a good marked zoom EP, to find the optimum power for the seeing and filters if necessary.

14:HIGHLY ACCURATE FOCUS - TOGETHER WITH A NICE FLAT FIELD, FREE OF CURVATURE - this is a must also , and you may have to re-focus often.

15:VERY STABLE MOUNT - Absolutely no wobbles!

16:VIEWING AT TWILIGHT - Can reduce the glare of Sirius A - and this goes for other bright primary doubles as well!

17: HOOD or COWL; this WILL help if streetlights or other bright light sources are a nuisance -- I rarely observe without one in any case!


PS: If something has been overlooked, we would all welcome further additions!

bigjoe.

[The_bluester]

A quick report from Snake Valley. Last night was not looking at all promising until near dark when the sky cleared up nicely.

In short, we got it! For about an hour, Sirius and the pup were clearly visible and separated in the C925 and a couple of other people snagged it as well both through my scope and their own (most of which were a lot bigger)

It took a few minutes to see and I resorted to moving Sirius just out of view but once spotted it was repeatable with Sirius centered in the FOV. After about an hour the seeing deteriorated and the airy disc of Sirius put an end to seeing the pup.

[bigjoe]

Glad you found it Paul.

bigjoe.

[The_bluester]

Yeah, it was a very nice moment, very nice to grab a personal first for the weekend. I had another try the following night but the conditions were not as good leaving it just not quite there. Then it clouded over completely and it was a night for wine and talk rather than observing.

I thought a couple of times I could see it on the second night but was never quite sure so I am putting down to wishful thinking rather than an actual detection second time around, the first night there was no doubt once I detected it initially. I will hopefully have another try from home in the near future and see how I go there. The sky is not quite as dark as Snake Valley but pretty good and we often get pretty good seeing (I live about 6KM out of a smallish rural town and 60KM away from a major city)

Edit: to talk to a couple of the pointers in the list above.

1: SEEING - Must be excellent.

Yes, very good seeing in the early part of the night I was successful.

2: ALTITUDE - Well above the horizon in
most instances.

Sirius was near it's peak elevation above the horizon at the time.

3: APERTURE - 100mm+, Cooled and well collimated, though probably no more than 12" due to the affects of seeing on large obstructed scopes; though it now appears certain, that even a 70mm achromatic refractor of long focal length can result in DETECTION!

Detected in a CPC925 so about 235mm aperture. I tried with a 130mm refractor as well but did not manage detection, but I did not have a short enough EP to stack on the magnification.

4: POWER - The use of it is necessary - Helps darken sky background, and with limiting magnitude ; 200x + may be needed.

Detection was at 313 X mag in my case.

5: USE A MASK - Hex , may be necessary.

No mask used in my scope nor in the big dob where we also had success. The pup was nicely between diffraction spikes in the dob.

6: ORIENTATION - Is your diagonal/scope displaying an upright E/W view; If not adjust accordingly.

Caused a little bit of mental adjustment between scopes due to different orientation.

7: PRACTISE on Rigel say - Bright, with similar separation. Know what a separation of 10" will look like in your go - to EP - VIZ - Know your field.

That was the first step, a seeing check and mental check of the rough separation on Rigel first.

8: DRIFTING - Let Sirius A drift past the field stop , and disappear, as B will surely follow.

First detection made by this method, I used slow motion slew controls to move Sirius just outside the field stop.

9: WARM CLOTHING , and stool if necessary.

10: PATIENCE - and lots of it - It could take many attempts!

Thrilled to bag it on the first attempt. Failure on the second night I think an indication of the seeing conditions on the first.

11: LESS GLASS - Use of EP with fewer elements 4/5 max to increase contrast and detection, may be of help.

Possibly yes, EP in use was a Plossl in a 2X Barlow.

12:AVERTED AND DIRECT VISION - Go back and forth between direct and averted vision, until the companion is held in direct view.

Done, initial detection with Sirius out of view, later detection with averted vision, a bit more practice with direct vision in the C925. Easy with direct vision in the big dob.

13: ZOOM EP - Use of a good marked zoom EP, to find the optimum power for the seeing and filters if necessary.

14:HIGHLY ACCURATE FOCUS - TOGETHER WITH A NICE FLAT FIELD, FREE OF CURVATURE - this is a must also , and you may have to re-focus often.

A small focus change and it was gone.

15:VERY STABLE MOUNT - Absolutely no wobbles!

16:VIEWING AT TWILIGHT - Can reduce the glare of Sirius A - and this goes for other bright primary doubles as well!

First detection was in late twilight.

17: HOOD or COWL; this WILL help if streetlights or other bright light sources are a nuisance -- I rarely observe without one in any case!

[bigjoe]

Just goes to show Paul, it's not as easy as some might suggest.

A big scope you have really, 9 1/4 with its flatter field than most SCT's; would have been very good for this, but not the 130mm refractor that's interesting!

You did everything right as per list, so well done!:thumbsup:

PS: A personal first too. Sirius B is something every Amateur should bag.

bigjoe.

[The_bluester]

I am probably not being entirely fair on the refractor which was very very nice to observe through and gave lovely low powered views of the same objects that we were observing at higher power through my SCT. Mainly M42 and Eta Carina.

In it's defence time ran out to stack on the power, with the EP we had handy for it we were limited to about 115X mag though it might still have been doable with more patience. Hopefully I get the chance to view through it visually again (It is chiefly used as an astrograph by its owner) and if it is still early enough in the season, have another crack splitting Sirius with it from home.

Something I found very interesting was the difference in the airy disc between my C925 and the big dob. The SCT at high power produced a disc looking pretty much exactly as the Celestron manual would lead you to expect when collimating, basically a small but sort of broken, fuzzy disc made up of lots of little concentric ring sections buzzing around the centroid of the image. The dob produced a noticeably tighter and cleaner star image which led to better apparent separation between the two with the obvious addition of diffraction spikes from the secondary spider vanes. The biggest issue was that Sirius was almost painfully bright, it was easy to project a clear image of the star on your hand a couple of feet away from the EP!

[MattT]

Have given it a go over the last couple of nights around 11:30pm. Sirius at that hour is about 40º above the horizon and descending into the western murky sky. Melbourne on both nights was pretty awful and all I saw with the 70mm f13 and 90mm f11 Achro's was a ball of glare and no sign of the pup at all. Finding a sharp focus was impossible....conditions are everything.

Will now wait for early Spring mornings for the next try.

Matt

[Tinderboxsky]

Well, at last I can report in that I have been able to spot the Pup this viewing season.
Last night was the first clear night without the coastal cloud that has been a constant companion for many months. Seeing and transparency was excellent but with a near full moon approx 60 deg away.
The Pup popped out easily when holding Sirius just outside the field stop at 320X. Once seen, the Pup reminded visible when moving Sirious back into the FOV. I reduced magnification to 200X and was able to maintain seeing the Pup. scope was NA140SS with Baadar Fringe Killer filter on TRex mount. I did not have my ED103 on hand to try the Pup with that aperture.
Then got distracted by some magnificent views of Jupiter.

Steve

[Tropo-Bob]

Well done Steve.
As for me, I have not had a clear night since I have seen the Pup!

[MattT]

Good one Steve :thumbsup:

To prove to myself I wasn't seeing things I decided to throw my biggest scope at it and got out the 10" f4. 8 Newt. After a few minutes I was rewarded with the Pup...a dull slightly green star, further out from Sirius than I remembered it to be. Eyepiece an ES 8.8 82 giving roughly 133x with a 2mm Exit Pupil.

As the finder on the Newt is a 60mm f5.5 ED refractor I put the 8.8mm eyepiece in that scope and saw...nothing.

[Tinderboxsky]

Thanks Bob and Matthew.

I have made up some simple aperture stops and if I get another good night I am going to experiment stopping down the aperture and see what happens. I will only bring them out and try on a night of excellent seeing and Sirius is still reasonable high.

Steve.

[goober]

Tried from Melbourne last night with a 127mm APO and a variety of eyepieces. Seeing was quite good for Melbourne at 9pm. Spent an hour on it with no luck. Rigel was absolutely no problem with any eyepiece I threw at it, from a 13mm Ethos down to a 3-6mm Nagler zoom.

I could see the E star in the Trapezium with no difficulty, and the F star popped in and out.

The pup still eludes me.

Can anyone confirm the PA is similar to Rigel? I know the separation is at around 8-9". I was looking east of Sirius for the Pup, similar to Rigel, letting it drift into the FOV hoping to snag it before Sirius appeared.

[The_bluester]

Other way around, It follows Sirius so you need to let Sirius drift out of view not into it.

[goober]

Thanks. I am a muppet - talk about rusty...

[The_bluester]

No worries, good luck!