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David Fitz-Henr
06-09-2009, 06:52 PM
At the behest of my astro-mate Marcus (marc4darkskies), I thought I would show some of my first images from my foray into the world of deep sky imaging. These were taken last night (Saturday) under the light of the full moon. Actually, I was struggling to align the camera square with the optical axis, but after a couple of iterations I thought it good enough to take some shots.

1. M8 (lagoon neb): 10 subs at 150 secs each with dark frame. I think this turned out reasonably good, just basic processing using ImagesPlus - I didn't try to enhance the colours and I think it works well. I did a final tweak in Photoshop Elements (adjusted the mid point marker under the Levels menu - I'm not used to ImagesPlus but there's probably just as easy a way to achieve the same thing there I guess).

2. M20 (Trifid neb): 9 subs at 150 secs each with dark frame. Looking at this now, it could perhaps have benefited with some enhancements to blue and red.

3. 47 Tucanae : 7 subs at 240 secs each with dark frame (although dark was 150 secs - forgot to take a matching dark). I had to partly re-process this after I transferred the image to my main PC. For some reason, the stars seemed to be banded or washed out a bit when looking at my monitor, although it looked acceptable on my notebook monitor. Both are set to display 32 bit colour quality so was a bit surprised by the difference.

All shots were taken using an unmodified Canon 400D on a home made 200mm Newtonian (using Paracorr) on a Paramount ME. I don't have a guide scope / camera, so all shots were unguided. I limited the first two sets (M8 & M20) to 150 seconds for each sub, and pushed the third (47 Tucanae) out to 240 seconds. The stars look reasonably round in all, but perhaps if the seeing was better you could detect some elongation - hopefully next weekend will have better seeing (well, at least the moon won't be full !).

bert
06-09-2009, 07:42 PM
Now all the work you put into atm seems worth it, eh?

I'm quite jealous of your unguided tracking... I have to get a PME.

Nice work.

Brett

AlexN
06-09-2009, 07:44 PM
The optics look brilliant.. very nice sharp star images.. the M8 and M20 shots could do with some more saturation, but apart from that its all looking good! I would have thought a Paramount ME could track longer than 150sec without causing issues? or is that more of an alignment issue than anything else?

Lester
06-09-2009, 08:10 PM
Hi David, welcome to IIS. The star images are so crisp, and goes to show the capability of your Astrograph.

Looking forward to more images from you.

David Fitz-Henr
06-09-2009, 08:26 PM
Thanks Brett,
Yes, all the work in building the 200mm Newtonian (18 months spare time) as well as all the work building an observatory to house it (another 2 years of spare time). The Paramount actually spent most of the first two years after I bought it sitting in its box!

Thanks Alex,
You might be surprised to know the mirror is a cheapie "made in China" 200mm f6. Since the seeing is typically at least 2 arc secs, it just has to be better than that - the Paracorr does the rest of the work correcting coma, etc. Also alignment is critical - the camera still isn't perfectly square yet and I can detect some slight elongation in some of the corners.

As for the tracking, the 47 Tucanae subs were all at 240 secs (4 minutes). Actually, I did do a few single jpeg frames a couple of weeks ago to test the tracking. I did a 5 minute image where the stars were slightly elongated, and a 10 minute image where they were definite eggs. It may be possible to take a sequence of many images though and cherry pick the good ones. I found that all the 47 Tuc images were quite good, so I guess I can easily push above the 4 minute mark.

Yes, the M20 image definitely needs some more colour, and probably a bit more for the M8 would be good as well. Although, I do like the colours to be a little more "natural" than many others might - it would be interesting to hear all the different views on this.

Regards,
David

marc4darkskies
06-09-2009, 08:34 PM
Aaahhh - imaging at last!! :) Good stuff David!! ... and welcome to IIS!

You're a bit light on for colour saturation (= a little too natural for my tastes), but you've got some nice definition going on there for sure. :thumbsup:

Given they are your first astro-images, they were made through a home made telescope, they were unguided and they were taken near full moon using an unmodded camera you should be very pleased with the result!!

Now on to some longer, guided exposures!

Cheers, Marcus

2020BC
06-09-2009, 08:50 PM
An astonishing first foray indeed. Do yourself, and us, a favor and shoot that M8 again with 60mins of total exposure. That unguided mount sure is a beauty. Well done.

tornado33
06-09-2009, 09:41 PM
Excellent focus and tracking there. I was amazed to see such long unguided subs till i saw you have a paramount mount, which are capable of that.

With such a high quality mount you wont need a very big guide scope. You could then do 10 minute subs and go very deep. That conbined with the high quality optics would bring great results.

I note stars lovely and sharp right to the corners.
Scott

Hagar
07-09-2009, 09:15 AM
The images are Awsome.... The scope looks like it will be a real image killer and coupled with the paramount and active guiding I forone look forward to some really magnificent images from you in the future. As others have said these images could do with little more work on the colour saturation but you have some lovely quality data to work with.

Well done
Looking forward to seeing some more from you.

David Fitz-Henr
07-09-2009, 09:23 PM
Thanks Lester, Marcus, Bill Scott & Doug.

Yes, I'll look at tweaking the colour saturation next time (have to find that tutorial in the ImagesPlus demos - still learning the software). Actually, being an unmodified Canon it will be less sensitive to red - so another good reason to tweak the colours a bit.

multiweb
07-09-2009, 09:44 PM
All those pics are quite awesome. Your optics are certainly excellent. Well done. :thumbsup:

RobF
10-09-2009, 01:49 PM
Congratulations David on what looks like being the start of some great astrophotography. M8 is my favourite. You can just look right into the heart of it and the detail is all there. I hope we get to see more as you continue the adventure!

TrevorW
10-09-2009, 03:42 PM
Very nice a little bit more colour as suggested

Octane
15-09-2009, 10:46 PM
David,

Wow! That M8 knocked my socks off. I can imagine just how incredible that will look with loads of exposure (and appropriate darks and flats).

Congratulations on what looks like to be an incredible setup for wonderful astrophotography.

Well done!

Regards,
Humayun