Achro for luna photography .

[brian nordstrom]

Hi , here is a couple of shots from this last week taken of the moon in its waning phases .The last was 3am this morning after work ISO 400 1/4 second .
I hear all the time that the lowely old Achromat is no good for AP , well I disagree as these shots show .

Zero CA , super sharp , very dark background .

Taken prime focus with my Istar 127mm f8 Achromat , sony alpha 200 DSLR , zero work on these just straight out of my camera into my computer and posted here .
Replies welcome :) .
Brian.

[naskies]

Nice shots, but the edges of the moon are clearly green? :question:

[Peter.M]

Interestingly they are blue on my screen, I have just bought a new screen so it might be that.

[asimov]

Well yeah, they are taken in colour, hence the colour fringing from the Achromat?

Take it in mono & no fringing.

[brian nordstrom]

;) Time to buy a decient screen then , the edges are white in my Compaq Q2009 .
Here come the doomsayers , but please keep it coming ,,,,,
You kinda forgot that this shot is raw , it would be easy to cheat and process any defects out but that's sort of cheating .
Brian.

[Regulus]

Thanks for posting these Brian. It's important to encourage people to try it for themselves, and pictures like this helps.
We see some truly stunning images here from IIS members, and we see the sophisticated and expensive equipment they use to achieve their results. The equipment used often puts it outside many peoples budgets (time as well as money)
Ur photo's are encouraging proof that amateurs can get satisfying results with the basics. Certainly good enough to make there own attempts worthwhile, and give them a whole new reason to get the telescope out. And it must be satisfying to have photos from your hobby to show friends and workmates.

I'd like to see people posting some of their solar system pictures taken with standard viewing equipment+camera just for this reason.

Trevor

[Larryp]

Nice shots, Brian. I find it very difficult to detect any colour fringing on my computer.

[MattT]

Nice Brian.
Trevor has it in one.
Achro's are telescopes too.:D
Matt

[Nikolas]

No colour fringing here either

[skytry]

hi Brian,
NO colour fringing on my laptop screen,
good pic's,well done,
Peter.

[Kunama]

Nice pics Brian! My iMac does show a thin rim of green but I think overall too many people worry too much about CA instead of what is actually in the image.

(It was so much simpler when all anyone had was an achro, none of this apo v achro banter existed.)

[MortonH]

Very nice. That Istar is excellent.

[Profiler]

To my untrained and old eyes they look very nice but if you want some perhaps more discerning evaluation post some of these pics in the Solar System Imaging section and see what some of the dedicated AP folks have to say.

[04Stefan07]

Nice shots Brian. :thumbsup:

Hoping to see more of your work!

[OzEclipse]

Nice shot Brian. If you filter an achro, say with a red filter, you'll get rid of any CA. That's how they did it in the old days. These days, you can just pull the red channel out of the digital image. Do that and the fringe disappears.

One thing about your pic confuses me. You say it's prime focus of your 5"f8 refractor and 1/4s ISO 400. Intuitively, that seems much too long an exposure for that optical train and ISO. Are you sure it wasn't 1/400s?

cheers

Joe

[brian nordstrom]

:thanx: OOPs yes 1/400th , on the CA it does now bother me at all , its so slight when looking at the moon any way , nice lense that Istar .

Brian

[brian nordstrom]

:) Thanks everyone ,
Trevor , I will do some Jupiter , Saturn and mars shots next year when they are all back at a reasonable hour .
And yes I will post in the solar system imaging section and see what comes out .
Brian.

[bigjoe]

Impressive shots Brian. You're too honest ! You can cheat you know !

GET EM OF YOUR BACK !

Seriously these big achros get hammered by some, yet you have had all kinds of

scopes and can vouch for them for crisp visual, and AP general use.

I'll get one eventually.

CHEERS BIGJOE.:thumbsup:

[Satchmo]

At about 20X - X40 prime focus magnification with an Achro - which these shots represent, CA will not be noticeable . At X400, using eyepiece projection for a descent close up shot the CA in these Achro refractors will be absolutely objectionable in the pictures - even for visual observing pretty useless....

I am not sure exactly what you are proving in these photos - the subtext being that somehow CA in achros is an overrated criticism ?

Have attached a picture of Copernicus using frame stacking , by Anthony Wesley using a basic 10" F6 reflector in 2005 - just to put some perspective on this !

[LewisM]

I see blue CA on the fringe at the bottom of the second shot, but it sure does NOT detract from the image at all.

I tried DSO imaging in a 6" achro when I had it. The DSO was fine, the stars were VERY objectionable.

[TheFacelessMen]

I have a professional colour calibrated monitor for editing and the shots show green fringing on my screen as well

[killswitch]

There is some green fringing on the first photo, very faint no biggie.

1/400 is a bit too fast imo. Slow it down to 1/200~ so you can lower the ISO for better noise and dynamic range.

[casstony]

It's entirely normal to see a little fringing at low power and more fringing as the magnification increases, in addition to a subtle (or not so subtle, depending on the observer) mauve haze across the image, but even fast achromats can give very sharp and detailed images with the addition of filters.
In any case they're very nice pics Brian :)

[brian nordstrom]

So , in your expert opinion ( that you are more than welcome to share) what's so ( in your words) , ' Absolutely Objectionable' , about this shot ?
Taken with my terrible for luna photography 127mm Istar Achromat ?
This was taken eyepiece projection , 5mm TV Radian giving 200x , not quite dark , using my HTC one smart phone . Here it is .

Take your best shot old mate .
Zero processing , just a raw shot cropped a little for the page .;) .

On the Copernicus shot , just stunning ! awesome shot . Reminds me why I am a Luna , Planetary observer , so very well done .
But I need to ask how much computer enhancements have been done to acheave this beautiful shot ? :shrug: .

Thanks and keep em coming .
Brian.

[h0ughy]

Firstly, I think in my own opinion acromat’s are pretty ordinary for Astro photowork except mono work, and yes I can see fringing and colour on the edges – I have colour with my cheap 127ED as well. BUT, you asked a question or postulated a statement? – You got an opinion and because you don’t like and now you are prepared to belittle and bait the person that posted?

What gives :screwy:– an achromat is an achromat?


if you like it visually then great:thumbsup:

[Satchmo]

I said that I found the colour in my 6" F8 refractor objectionable for high power lunar and planetary observing.

Seeing as you ask , your shot has no contrast - the blacks are all bathed in a purple haze ..just as your high power views would be .

May I suggest stopping your scope down to 4" F10 - it would show less false colour . :hi:

[Kunama]

With ref to the pic posted in #24, I am getting a purple tinge on my screen on the left and some greenish hues in the highlights.
My screen has been calibrated for my son's graphics/photography work.

I think the effect is going to be there with any achromat. Personally I did find that the Istar 6"F10 I had was better than other achros I have used but that may have been due to the F10 ratio. My 135year old 3" F15 is the least colourful achro I have used. I did not really understand how much extraneous colour the achro showed until I put it side by side with the TSA120, the difference could not be missed on the moon, Jupiter, Saturn or brighter stars. But if I had not come by the Tak at such a great price at the right time I would have gladly kept the Istar.

But seriously these discussions of Achro v Apo v Mirror happen all too often and cause so much disharmony. Such a shame !

[Lee]

I think they are great shots Brian. :thumbsup:

The miniscule amount of false colour there (which I had to strain to see after it was pointed out) is certainly not objectionable to me....
I should do one through my Skywatcher 100mm f/5 - so much colour, it would look like there was a mardi gras up there!

[sheeny]

At the risk of inflaming the situation... a few people have mentioned that imaging in mono will fix the CA, but that, in itself is not quite right.;):)

Imaging in mono will hide the CA as another shade of grey. To get a truly sharp image requires the use of a filter before capture to narrow the bandwidth of the light being captured.;)

Al.

[UniPol]

I'm seeing every colour of the rainbow on my monitor, wait, I'll get back to you soon when I've sobered up :P

[Kunama]

B.......B.......BEROCCA for you today ! and cut out those magic mushies ..:thumbsup:

[issdaol]

Personally I thought the original two shots were nice shots especially having no post processing done so I dont see anything Absolutely Objectionable to the shots.

However the shots do show CA which also would have been visible visually so I dont think you could use them to support any claim that an Achro has no CA either visually or for AP.

Personally I just dont like to see CA visually but as I say that is just my personal preference and thankfully my scope shows no CA but that comes at a cost.

[brian nordstrom]

:thumbsup: Thanks Phil, at last some one with some common sense on this subject .
Spot on mate .:) .
This is what was trying to get across .

The CA is that slight its irrevelovent in my eyes .
On that the photo of 3rd quarter is almost identical to the absolutely beautiful image my TV Radian 14mm throws up , same image scale and lack of CA or any other aberrations as this shot shows , just beautiful .

On that , this is a $630 OTA not !! a 5k +APO ;) .
One more thing I hear you on the cost thing , my Takahashi Mewlon 210 is perfect in every way .

Brian.

[multiweb]

You can pick up a nice APO for under $1k these days, don't have to spend a fortune. I got a 90mm - F/7 last year to use with my OSC as the ED80 had bad color correction. You get green around the limbs because the blue doesn't focus where the red and green are. If you shoot mono it's still not as sharp as an APO but you can manage colors betters with a filter wheel.

[brian nordstrom]

:shrug: Maybe but I would hate to see the short cuts made to sell a 5 inch APO for 'under a grand' , thanks but I will stick with my 127mm f/8 Istar / saxon thank you very much , nice optics for sure .

Your shots are a great eye opener , but in the 'Blue' looks a bit sad tho ? and its a shame your ED80 was a dud , the one I had ( now sold ) had awesome optics .

Brian.

[multiweb]

:lol: Man... this is like talking to a wall.... you need to read all the previous post in this thread. Who knows? You might learn something. :)

[brian nordstrom]

:shrug: Say what ? easy Tonto .
Brian.

[multiweb]

This is a crop of your shot btw. Just wanted to illustrate that the blue was out of focus and explained why as did many people in previous posts so you know where to go from there.

[Regulus]

Did anyone here happen to notice the camera used to get these photo's?
HTC one smart phone.
So, of course it isn't to the standards that can be gotten with a more dedicated set up.
It was a bit of fun posted for a bit of fun, so get a grip.

What it says is that amateurs can have some fun AND have photo proof of the excitingly innocent way they spend their nights.

btw - if Brian says the CA is unobtrusive then... it's unobtusive.

Trevor

[brian nordstrom]

:lol: Cool , but I don't use/need filters with my Istar , it good enough for me , that's the whole point of this thread was to show how good our 'Lowely' old achromats can perform for lunar photography , not spending hours at a computer screen with X- amount or processing power to extract the last bit of info from the shot , Stacking , Mono , Colour ,, bla , bla , bla that's invisible to the naked eye anyway ,,, whew ;) .
And NO filters , thank you very much , I like my moon a,la natural ..:rofl:.. , that's the way it is in real life if I ain't mistaken , warts and all :thumbsup: .
Brian.

[brian nordstrom]

:thumbsup: Thanks Trevor , old mate , warts and all .:eyepop:It aint a perfect world is it ?
Brian.

[Satchmo]

Theres a nice ED120 going on this site for $1190. Or you can get a new Istar 127mm Achro for USD $1500 :shrug:

[brian nordstrom]

:thumbsup: I seen that , someone's going to get a bargain .
I have given my darling my credit card until that sells , great buy for a FPL53 f7.5 120mm doublet , I bet it performs very nicely ( without filters :rofl: ) The build of the Istar is in another league tho and the optics will be smoother , better figured and coated than the sweet mass produced Synta . But yes it will show CA but it will be very well suppressed , like mine .
Hand figured and built that's where the extra $300 comes from .
By the way a new 120mm ED Synta is in the 2k+ ball park dollar wise .
Brian.

[brian nordstrom]

:) Just to get us all back on track .....
This is a different photo , like all I have posted , different settings , I am still experimenting .
Brian.

[cometcatcher]

I think your raw Moon shots through an achro are quite pleasing Brian. I also like to view and shoot the Moon with my achro.

[Den]

Hi Brian,

I think your shots look good, I have got a Megrez SD 80 which shows some CA but she is very sharp.
I used my cheap mobile phone to take a shot (camera on a steep angle) using my TAK. I have found the blue moon. This is why you have this colour too it was a blue moon last month.:rofl:

Regards

Den