Well, i'm stumped. Image stacking related

[Tenuous]

I've spent close to 6 hours on this subject now. My interest in basic astrophotogaphy led me to this website http://digital-photography-school.com/how-to-shoot-the-night-sky-introduction-to-astrophotography,

In the article, the author details a great method of taking multiple exposures and stacking them using Deep Sky Stacker, then links to a great YouTube video describing the processing stage. Looks like a lot of fun, so I head outside and take a set of pictures.

Everything sounded like it would be a cinch, and I followed each step and instruction. Where I have been hitting a brick wall for several hours now is Deep Sky Stacker. I'm supposed to load Dark, Light, Flat, Dark Flat and Unbiased images (according to this video http://www.youtube.com/watch?v=UWWaKkCUm6c) to stack the images and then create a TIF file with them. What in the heck are those? I can only load dark images, and I can't find any information anywhere explaining the process of creating sets for each of these types.

What am I missing here? Almost every article I've read makes the process sound so simple, yet I feel like everything is one homogenized mess.

 

[610nm]

Although I am the wrong person to answer your question, I think you came to the right place, because there seem to be a lot of knowledgeable 'sky people' here.
Don't worry about the TIF file, that is a great file format to work in, you can load one into PS and then save it as a JPEG when you want later.
The rest of the process sounds cool though, so keep at it, someone here will know about this.

 

[little big man]

I think this is what you're wanting to know:

http://deepskystacker.free.fr/english/faq.htm#lightdarkflatoffset

Sean

 

[Tenuous]

I think this is what you're wanting to know:

http://deepskystacker.free.fr/english/faq.htm#lightdarkflatoffset

Sean

Urgh. It was so simple. I must have missed this portion of the help section when I initially went through it. I was so tired and frustrated. Thanks for pointing that out.

Looks like i'll be going back out tonight, weather permitting. Much appreciated!

 

[milbournosphere]

The dark frames are taken at the same time you're taking the shots for the trails shot. After you're done, shoot a few frames at the same camera settings with the lens cap on. This frame should be entirely black, but will also capture the sensor noise. Load these in and the stacker will do its best to scrub out that noise when the photos are stacked. I've used two to three dark frames along with the shots and the results are usually pretty clean. Still a little noise left, but that's expected when you're shooting 30s + exposures.

 

[Tenuous]

The dark frames are taken at the same time you're taking the shots for the trails shot. After you're done, shoot a few frames at the same camera settings with the lens cap on. This frame should be entirely black, but will also capture the sensor noise. Load these in and the stacker will do its best to scrub out that noise when the photos are stacked. I've used two to three dark frames along with the shots and the results are usually pretty clean. Still a little noise left, but that's expected when you're shooting 30s + exposures.

So you use DSS then? I was going to go out last night and try it again (I did a test run with a picture I took inside and figured everything out), but I slept through the night. I'm going to try again tonight, but here's my question if you use DSS:

1. Do I need to incorporate Unbiased and Dark Flat exposures or are they redundant if I already have my dark exposures? One of the tutorials I watched recommended 20 of each type which would amount to close to 100 exposures. That's a lot of data for just one photo.

 

[Tenuous]

This didn't turn out like I wanted it to. I'm not too disappointed with myself, since it was my FIRST real attempt at astrophotography. It didn't help that I did it from my back yard with no tripod, and plenty of light pollution in the area. I plan to go out of city limits and try again. For now, this was more or less a test to ensure the stacking process worked.

Overall, pretty mediocre but at least I know my stacking worked. I still get a lot of vignetting, and for some reason when I edit levels and curves it works in the opposite way of the tutorial videos. So I end up getting a very light picture with little emphasis on blacks.

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