First session with the Argo

[Lismore Bloke]

Finally some scope time after weeks and weeks of cloud and rain.
This one is just a list of objects (mainly bright ones) spotted to test the Argo in tour mode:

GALAXIES:
NGC 1097, NGC 1316, NGC 1365, NGC 289, NGC 253, NGC 134, NGC 55, NGC 134, NGC 55, NGC 7793, NGC 7713.

PLANETARIES:
NGC 7293 (Helix), NGC 7009 (Saturn), NGC 6818 (Little Gem), NGC 6853 (Dumbell), NGC 1360 (in Fornax). This last one was particularly striking and distinctly oval shaped. It will bear closer examination. I think an O-III filter might find its way into Santa's bag of presents this year ... if I'm good!!

GLOBULARS:
NGC 6934, NGC 7099, NGC 6981, NGC 7089. I think there were a few others as well.

Uranus and Neptune were also picked up.

Conclusions are that the Argo is an excellent aid in maximising my precious telescope time. It needs some fine tuning, as not everything was in the FOV, but it was close enough to be picked up. Thanks for looking, Paul.

[sheeny]

Its a good bit of gear, isn't it Paul?

A little tip I use... not sure if you're doing this or not... but when I find an object is a bit off (particularly when you slew to a new piece of sky) when I find it, I exit the tour, do an align on it (in this mode it doesn't have to be a star), and then resume the tour.

There's nothing like an Argo, I reckon, for maximising the number of objects you can view in a given time.

Al.

[erick]

Which scope, Paul? and which eyepiece were you using as you moved to a new object?

[astroron]

Great stuff Paul:) you will never look back after getting the best out of your ARGO.
The best will come when you fine tune your technech:thumbsup:

[Gas Giant]

I installed an Argo on my 25cm Dob some years ago. I've had this telescope 14 years and I've been looking at the latest large aperture go-to Dobs that cost about the same as my telescope did back then before the Chinese manufacturers of Skywatcher etc. got into the market. In 1996 I paid $2,200 for an Orion Premium Deep Space Explorer with a JMI Crayford focusser. Now for under $3000 I could buy a 14" Synscan Dob.

The trouble is, I don't want to say goodbye to the Argo Navis. If I ever sold this 'scope the main selling point is that it is fitted out for the AN.

I thought I would buy an auto-tracking Dob and get new encoders for the Argo - but unfortunately the encoders won't fit these 'scopes.

As you are by now probably aware, I'm a BIG fan of the Argo. I will use my old - but very good - scope a while longer while I ponder - preferably out under the clear night sky.

Happy hunting:)
Andrew

[Lismore Bloke]

Thanks everyone,

The main 2 EP's used were the Nagler 22 and 17. My alignment stars were a bit too close for my liking, Achernar and Al Nair (Grus). Everything else was below the horizon, behind the house or trees. I don't know if that affects accuracy.

Al, I was wondering if you could re-align on it or somehow reset it. It seemed to be off by about the same amount, but only in one direction. I might email Gary if the book doesn't shed any light on it. Overall though I'm very impressed by the system. Gary needs to revise the book though, as there are lots of posts asking about setup and other basic issues. Seems to indicate that the instructions are not worded clearly enough.

[Lismore Bloke]

Sorry Eric, the scope was the GSO 12" dob bought from Andrews in Sydney.
I used the 22mm and 17mm to ensure a wide field. I usually use the 12mm for galaxies unless the targets are big units like NGC 4945.

[erick]

Hi Paul. I think you'll find that the manual is clear but we just don't quite "get it" on the first few reads in some bits.

I asked about the scope because I suspect your dob base might be a bit "sloppy". The older GSO ones were. Watch for flexing of the two side walls as the scope is elevated and lowered. Also look to see whether the tube unit is moving a bit along its altitude axis (the axis through the trunions) as you move it up and down. I found that a little mechanical work on the base to deal with both these problems assisted.

[Lismore Bloke]

Thanks for the reply Eric. Sounds like a bit of bracing might stiffen the structure up a bit. These dob mounts are not exactly precision engineered!!

[Paddy]

Good to see a post from you again in this section Paul, it seems a long time - more so for you if clouds have kept you from observing. Quite an impressive list - clearly the benefit of the Argo. Looking forward to more reports

[andrew2008]

Sounds like it was a great night. With so little time to spend observing these days I really will have to invest in the Argo also.

[Lismore Bloke]

Thanks Patrick and Andrew,

I know there are some who don't really agree with devices like the Argo, thinking that one should learn the sky by star-hopping. While I respect those views, my telescope time is rather precious and anything that will help me find things quickly, and spend quality time at the eyepiece is worth having. I saw more in that short session than in any 3 normal sessions trying to find things by map, torch and star-hop.

[erick]

Did my time star-hopping. Worthwhile for everyone cutting their teeth on that, I think. I find it sad when someone just wants an NGC number to punch into a Go-to, and has no idea of where in the sky the object is - and what is in its vicinity. But after long searches to find the Blue Planetary (should have been easy :shrug: )and Hind's Crimson Star, I thought - if there is a tool to maximise viewing and minimise searching, why not employ it?

With regard to the GSO base, I effectively did two things:-

1) I tied the two vertical supports rigidly together closer to the open end (rather complicated given the OTA has to go in and out of this gap)

2) I added two metal plates that kept the trunions from riding back and forwards across the teflon pads. (pretty easy)

[Paddy]

I think the question of time is very important (BTW I'm pretty sure that you know the sky quite well by now). I feel that I have quite a lot of time for observing under good dark skies and so feel quite luxurious about mucking around finding things. If you don't have this luxury Argo is the way to go. So I imagine your obs reports are going to be quite a bit longer now - excellent!

[sheeny]

Exactly.

Al.

[Lismore Bloke]

[QUOTE=erick;650137]Hi Paul. I think you'll find that the manual is clear but we just don't quite "get it" on the first few reads in some bits.

You're dead right guys, I'm just impatient. Fortunately Gary from Argo seems to be a very helpful and obliging chap. He helped me at all sorts of odd times, business hours or not. Outstanding customer service and dedication to supporting his product.

[sheeny]

[QUOTE=Lismore Bloke;650274]

:lol: You're not alone there, Paul. We're all like that when we get new toys!

Al.

[ngcles]

Hi Paul,

Good to see you've joined the "Argo" club and you can see the benefits already -- more (much more) productive observing!

I'm confident you get the small pointing errors fixed up pretty soon -- don't sweat it. On my 18", about 70% of the time my targets land in the inner half of a 12mm Type II Nagler field that is 27 arcminutes across. Therefore, most of the time, the pointing error is about 7 arcminutes or better and that is impressive in a home-made truss-tube dob that (like all long telescopes) will sag a fraction depending on where they're pointed.

Yep the customer service is 1st class. It'd be hard to beat anywhere in the world.


Best,

Les D

[Lismore Bloke]

Thanks for the encouragement Les,

I think I'll add a couple of brackets to brace the inside of the side plates. perhaps another couple to stop the alt trunnions from squirming about.
The closeness of the alignment stars (Achernar and Al Nair) probably contributed. Need more alignment stars for the Argo!

Cheers, Paul.

[mental4astro]

Oh you lucky, lucky boy!

We expect much more extensive reports now, mate!

[astroron]

Hi Paul, if there are not any convenient stars available you can also use the planets to align your ARGO NAVIS, or a combination of both Star and Planet.
Read the manual as to how to do this:)
Cheers

[ngcles]

Hi Paul,



Yep, the alignment stars may well be part of the problem. They are probably a little too close to each other and maybe too similar in altitude.

With a dob, from my personal experience, steer clear as far as possible from stars close to zenith (Dobsons hole) where the encoder tics are very, very closely spaced on the sky. Pick stars as far as reasonably possible apart and at significantly different altitudes. I personally don't use stars above 60 degrees elevation (as I suspect Al Nair might have been when you aligned) for aligning at all and try and aim to have one at about 30 degrees elevation and another at about 45 degrees elevation as far apart as possible. Might I suggest this month for early evening (about 8pm) Alpheratz (Alpha Andromedae) (bottom right in the Great Square of Pegasus when you face north) and Achernar (Alpha Eridani).

When you are doing a re-align on another object (as someone suggested) bear in mind where the last thing you aligned on was. For example, if you aligned on Achernar and then Alpheratz (in that order) when setting up, and then a half hour later decided to do a re-alignment on M15 while you were observing it. The alignment objects it then works on from that point are those last two (ie M15, Alpheratz) -- and they too close to each other for the alignment to be "well sampled".

Some people tend to go a bit overboard in the accuracy with which they align, using ultra high-power reticles etc to make sure it is exactly centred at x500. I don't think this is really needed if you take my advice above. I align usually using a 12mm or 9mm Nagler at x185 or x247 and just make sure the star as close as can be easily managed to centre of field and then hit the button.

Make sure your "Fix Alt Ref" step is done properly and that the two axis of movement are at right-angles to each other (or at the angle you have set anyway).

Also, make sure your "refraction" is on too.

I'm certain you won't regret this purchase -- excellent piece of kit! Best to run it off a small lead-acid 12V battery -- they are power hungry.


Best,

Les D

[Lismore Bloke]

Thanks Les and Ron, I really appreciate the advice. My restricted northern horizon eliminates many guide stars in that area. The planets, however, are nearly always visible above the roof, even in winter. If I can't achieve the necessary accuracy suggested by using the standard Argo guide stars, I may just do that. Read ze book!!!!!

Cheers, Paul.