What are some good tips for astral photography?

[Audionut]

WB/Tone/Clarity/Vibrance

The adjustments vary depending on the lens/body/exposure.

Here it is direct from camera.

[glubber]

Has anybody tried making a star-timelapse using silentpics?
Even with applying NR and heavy tweaking in Lightroom on the DNGs the results are unusable.
While doing a timelapse with CR2 and the same exposure values (13"/f2.8/ ISO1600) look very pleasing.

I know about the lineskipping with "simple" silentpics, but is it just a WONTDO or have simply done wrong? 

[dmilligan]

@glubber,
Night photography is incredibly demanding on the camera. I can't imagine some liveview hack being useful for it in any way. People are so afraid to use their shutters and I don't really understand why (yes I know shutters do eventually wear out). At night you must do everything you can't to get every last ounce of performance out of you camera just to get a picture that's not terrible. That means use the shutter.

For me time under the stars is very precious and I want to make the most out of it. I wouldnt even consider wasting precious time with silent pics or even shooting on jpeg quality. Do the math on how much it costs per hour to take 30s exposures assuming your shutter wears out after 100-150k uses and it costs $200 to replace and I think you may see my point.

Haven't been able to get deep sky stacker working how I want it yet.  But here is a single frame from my adventures.

This was using my brother in laws Tonika 11-16mm f/2.8 @ 16mm on the FF body.

I've never had success stacking wide angle shots that aren't tracked (and if you can track there's not much reason to stack, just take a 10 or 20 min exposure). If you think about it it makes sense why. Wide angle lenses introduce significant distortion. This means as the stars move in your frame, stars in different places are going to move different amounts, in slightly different directions. This makes registration extremely difficult b/c the software has to take into effect distortion (I'm not sure if DSS can do this, I know that the software I use, pixinsight, pretty much chokes on them and it is significantly more advanced than DSS), not just linear translation and rotation. I read about some guy who managed to do some wide angle stacking with some rather sofisticated math/custom software he designed to take the distortion into account. And even then the results where not particularly impressive, very blurry toward the edges (where distortion is the greatest).

Fortunately tracking is not very difficult esp. with wide angle lenses b/c you don't have to be all that accurate. I use my telescope's equatorial mount, which would probably only cost around $150 by itself (my scope and everything was like $400). You could probably put together a simple barn door mount for less than $50.

[Audionut]

I actually didn't have much trouble in aligning the images.  My main concern was getting the required information in the tiff file.  I just can't seem to get the tone adjustments out of the tiffs as I can with the original raw files.  This is probably from my own lack of understanding of all the options in DSS.

Wide angle with tracking mount would simplify matters greatly.

[RenatoPhoto]

@glubber,
I've never had success stacking wide angle shots that aren't tracked (and if you can track there's not much reason to stack, just take a 10 or 20 min exposure).

Here is a stack of 20 photos taken with 5D3 without telescope mount or tracking, just used my Canon EF 300mmf/4+2X = 600 f/8.  (I wish i had the f2.8, but cant afford it)
Image taken at 2 seconds (lots of blurr) ISO 6400

DSS aligned them pretty well and got rid of tons of noise.

[dmilligan]

Explain to me how a 300mm lens is considered wide angle.  Last time I checked they were called super telephoto. He's using an 11-16mm lens, your using a 300mm difference is night and day. Yes stacking anything more telephoto than about 50mm works fine, I do actually successfully stack photos from my nifty fifty. I was talking about wide angle lenses, which have way too much distortion to align and stack

[RenatoPhoto]

Explain to me how a 300mm lens is considered wide angle.  Last time I checked they were called super telephoto. He's using an 11-16mm lens, your using a 300mm difference is night and day. Yes stacking anything more telephoto than about 50mm works fine, I do actually successfully stack photos from my nifty fifty. I was talking about wide angle lenses, which have way too much distortion to align and stack

I did not mean to offend you!  I have done some stacking of fisheye and still works, it certainly helps reduce noise.

[dmilligan]

Sorry that came off a little snipy.

No doubt it helps with noise, but how do you align them? Alignment algorithms typically work by analyzing distances and angles between stars and matching them up to stars in other frames. If distances and angles are changing due to distortion, the algorithms are going to have trouble matching stars. Also, typically these algorithms are only capable of applying linear corrections to the images such as translation, rotation, and scale. Distortion requires nonlinear corrections to be applied to images, which like I said is possible, but only with some rather complicated math and modeling of the distortion created by a specific lens. And nonlinear transforms are also going to reduce resolution as you move out from the center of the image.

Watch how the stars move on a fisheye timelapse to see what I mean.

[RenatoPhoto]

No doubt it helps with noise, but how do you align them?

I dont know but DSS does a great job IMHO, but I am not an expert by a long shot.  I have played with this software and always the outcome (Autosave.tiff) seem a lot better than any single image so in my opinion it works but maybe not to perfection.

[fotojohni]

The fps over ride is an absolute must!!

http://www.jakeevansphotography.com/85/

Also, ettr as much as you possibly can. Then crush in post.  I suggest using a wide angle prime because of the reduced vignetting when stopping down.  Vignetting is the biggest enemy, next one is sharpness in the corners.  Look for a lens without a curved plane of focus. 

It can be very difficult to deal with the shadow areas in the photo.  You can try to speed light them, but it usually looks like shit.  You have to be creative.   

The most important thing is to take some time to analyze the scene and compose shots effectively.