Astrophotography - M8/M20/M17

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Finally got to get out and use my Astrotrac setup I built to get some astro shots...I'm still combing through them but I did a quick edit on 1 image before I head to bed.

this is M8 (aka lagoon nebula, the largest one on the bottom portion of the screen)
M20 (aka the Trifid nebula, which is the smaller pink and blue one just above M8)
and M 17 is up at the top left corner (akla omega nebula)

Its late so I may need to go back and re-edit when I'm a bit more rested...I'll probably also crop a closer shot of the nebula too...

This was a single image taken at 135mm, f2.2, 30s, ISO1600 (no stacking multiples/darks/lights/bias/etc, just a straight single raw edit and conversion) Luckily I live close to some extremely dark skies, and this was taken a couple hours after the moon set so the sky was nice and dark...

M8-M20-M17_zpsc9052608.jpg~original


I'll try to get more up as I'm able to process them in the next few days.
 
Gorgeous! Tlhe thing about starry fields, is that the noise kinda blends in with the real stars. So looking at the image, I'm tempted to say "what noise"?
 
Thanks! yeah, plus this is probably like 70-80% of the full frame too, so the downsize to a small web size image also eliminates the majority of the noise too. if it was 100% crop you'd see it for sure...I'll need to get working on some more tomorrow.
 
One thing I learned is to not take 30 seconds. I have a friend who does this and he said for me to do half that. $DSC_4898.jpg$DSC_5070.jpg $DSC_5070-2.jpg these are my shots with 30. Wish I would have done it at 15. I wish I did not have to put these pictures on here so small. Because it does not do its proper justification. I love the first shot, but love the second one with the two love birds in it.

I wonder what would take place if you pulled back a little in the zoom. If that would help with the noise. I know when I zoom in on my crap lens, it gets noise about 120-150 depending on the hour I am shooting.
 
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this wasn't with a zoom, it was a Zeiss 135 f2.0 ZF.2 APO prime lens...the noise is due to the 1600ISO, so adjuting the focal length shouldn't make much, if any, difference in noise. I've got a mount which tracks the stars movements so the 30s exposure wasn't much of an issue with star trailing, maybe slightly higher heat noise, but nothing some stacking shouldn't help with.

I got probably 12 exposures I should stack which will virtually eliminate the noise, this was just a single shot I wanted to get edited right after I got home to see how it'd turn out. all the white dots in the image (tons, I know) aren't noise, they're actual stars (or other real celestial objects), I live close to some of the darkest skies in the nation, so getting away from city lights is pretty easy. its the color noise and luminance noise that I'll get taken care of with the stacks.
 
Wen I first saw it I thought it was more stars. but then was unsure with the comments. so thanks for clearing that up. And that is awesome that zoom did that on it's own. I thought those shots were only possible with telescopes. So now I want to go take my cheap lens and see if I can pull off anything close to your shot. (but my major problem is being in Georgia. I can go out into the woods. but still there is always lights around and light pollution no matter where you go in Georgia, in my opinion.)
 
heh, the zeiss 135 isn't a zoom, and is is anything but a cheap lens, I actually recently sold it (just waiting on payment, so I'm using it in the interim) because it was too expensive to justify keeping it around (retail on them is $2200 I believe). its THE sharpest lens ever tested by DXOmark, beating even the otus and 200f2. I wanted to mount my telescope on it but I'm still fabricating a counterweight system to get it to balance correctly on the astrotrac, I might be able to get my 500f4 to balance though, I'll have to try that next time, I'll need to do a better alignment for those kinds of focal lengths though.

yeah, light pollution in the south will be very hard to get away from, but you can try to get as away as possible. remember to be aware of your shutter speed if you're on a fixed tripod though, you can easily get star trailing. my astrotrac actually counteracts the earth's rotation so I can do longer exposures.
 
yep that is why mine has the blur in it. I'll have a better shot this weekend of it.
 
cool! post 'em up when you get a chance.

yeah you can also lower your shutter speed, and take multiples to stack them together to combine their light, so for example 2x 15s exposures stacked can roughly equal a single 30s exposure, and you can take even more to stack for the purpose of noise reduction, and reduce or eliminate the star trailing depending on what focal length you're using...though stacking becomes more difficult if you've got something terrestrial (land/trees, etc) in the frame since each frame will be a different relationship between the stars and the landscape...still do-able, but just more time consuming.
 

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