Lagoon Nebula through unmodded 50D

[jmx]

Went out for my 2nd night of astrophotography ever and had a great time seeing new stuff. This photo is about 30 minutes of exposure (33 1 minute exposures stacked) at ISO 800. 750mm @ f/5.

http://jmx.ls1howto.com/pics/m8_medium.jpg
There may be a tad more detail in the full res one, but not much: http://jmx.ls1howto.com/pics/m8.jpg
I wasn't too sure I'd get much since people seem to say you are better off with a modified camera (one without an internal filter) but I think it came out just fine.

[gjl711]

Very nice shot. I agree with you, came out great.

[Nighthound]

This is amazing, your second night out and you grab this kind of data. Fantastic work. Maybe the best 30 minutes I've seen on this object. I'm pretty sure you could coax out a bit more detail in Photoshop using curves.

If you can frame this up the same way(or close to it) next time out you can add to this batch and really step it up.

I don't underestimate the ability of unmodified DSLRs. There's plenty of red channel info in this, less than a mod yes, but not an outrageous amount. I've been shooting with an unmodified 20D and 5D for years and like the results plus they can pull double duty during the day.

Don't forget to enter your M8 or M20 shots in Challenge#4 on this page.

Great work, keep 'em coming.

[jmx]

Nighthound, thanks for the feedback. I actually took over an hour of shots with it, but about 50% of them were throw-away due to what I assume is periodic error in my mount. I was left with 33 minutes worth of shots (33 of 62). It's frustrating to have so many ruined shots, but rewarding to still get neat images out of the cheap gear (CG5 mount, no guiding, coma-hell newtonian).

I do think I can get more detail, but I didn't want to go overboard. I did do another pass or two of curves for a version I had printed since prints seem to come out darker. I suppose I could apply one or two more passes on the "for web" version as well.

Thanks again.

BTW, where can I find this "challenge 4" contest?

[Celestron]

Very Very Nice !

[Nighthound]

Nighthound, thanks for the feedback. I actually took over an hour of shots with it, but about 50% of them were throw-away due to what I assume is periodic error in my mount. I was left with 33 minutes worth of shots (33 of 62). It's frustrating to have so many ruined shots, but rewarding to still get neat images out of the cheap gear (CG5 mount, no guiding, coma-hell newtonian).

I do think I can get more detail, but I didn't want to go overboard. I did do another pass or two of curves for a version I had printed since prints seem to come out darker. I suppose I could apply one or two more passes on the "for web" version as well.

Thanks again.

BTW, where can I find this "challenge 4" contest?

You're very welcome. Click on page two of this section. Not many entries so it got bumped from this page.

It's hard to determine if periodic error, alignment, balance or any combination of these can be the issue. And then there's the possibility of some other mechanical hitches that can play in as well. It took me about a year to work out issues and fine tune my G-11 to get the most from it. I started by learning to drift align my mount. Then I cleaned all gears with denatured alcohol(w/toothbrush) and relubricated them with a high quality lubricant. My last tasks was to get the worm gears adjusted properly and then learn to properly balance my scope/camera/accessories at set up.

I'd ask you to post a poor subexposure if you still have one but since the exposures are so short it likely won't tell us anything definitive.

Shooting at 700mm is going to be challenging with a fine tuned CG-5 that is balanced and aligned well. So in order to have the best results it might require some troubleshooting to try and eliminate as many obstacles as possible. I realize you are just starting out so I'm not suggesting that you must do these things to get good results because you've already shown you can. But in order to go deeper(longer exposures) and get the best yield of keepers per night you will eventually need to address any gear and set up inaccuracies. Down the road you may want to consider a guide scope for autoguiding which will help quite a bit. For now I would say keep doing what you're doing, learn all the basics and have fun first and foremost.

[Catanonia]

wow awesome shot on an unmodded dslr

[A.S.I.G.N. Observatory]

Your second night out? WHAT? Your kidding?!!!

Fantastic work, just fantastic. The colour is good, stars are sharp, black-point set nicely.

There is a bit of vignetting (darkened extremities)and some elongated stars in the corners. Using a field flattener can fix the stars and taking some flats via a white t-shirt stretched over your scope with an even light behind it will get rid of vignetting.

Other than that, very well done!

Baz.

[jmx]

Nighthound, I think the orion autoguider is in my future, however I'm concerned about weight on my CG5, and I also do these shots with no laptop at all. Just the SLR attached to the scope, and the little canon timer device plugged in. I'd want to get a stand-alone autoguider if possible, and that up's the price of entry.

Catanonia, Thanks for the compliment.

Baz, I have practiced a couple nights on my patio, but I can see maybe 10 degrees of the sky at most and the light pollution in los angeles is pretty extreme. I see maybe 15 stars in the night sky? Gotta drive 80 miles away to get shots, and this was the second time to really be able to shoot subjects.

The "field flattener" you speak of is also called a coma corrector right? Maybe its a coma corrector for newtonians and a field flattener for refractors? If so, I don't think I have any options there....my telescope is a 6" newt with a 1.25" focuser, and there seem to be no 1.25" coma correctors. In hindsight I should have bought an 8" newt that came with a 2" focuser, but hey...first telescope, gotta make the mistakes to learn something I suppose.

Thanks for the advice on flats...I've been ignoring them totally since I haven't really understood what it added, but I think that is a good thing to tackle this month.

[T&E Run]

That is an amazing picture. I have no idea what you mean about 30 one minute pictures stacked. I guess I have some learning to do. I love it.

[gabebalazs]

Wow, this is a great image!!! Inspires me to try something like this (dreaming...:) )

[MidnightSun]

Not a bad shot for your second year out.....Nice Shooting

[markjpcs]

Excellent shot!