Stacking RAW Files

[Tom_88 (Thomas)]

Hi everyone

I am new to astrphotography and I have afew questions about stacking RAW Files and editing them.

For starters I have been shooting JPEGS which come up quiet nicely through my 550d. I have tried stacking say, 7-12 jpegs WITHOUT darks, flats and bias in DSS and they also come up nice. I tried shooting RAW images and they come up well on the LCD but when they reach the PC they are high in detail but also quiet noisy aswell.

I read somewhere that you need to denoise them beofre stacking etc, but upon stacking them in DSS the final image appears a vertical strip with little to no detail.. The current photo editing software i have is Picasa3, DSS, PhotoShop 7.0 ( heh bit old eh ).

Any help would be greatly appreciated! Thanks heaps!
Cheers! Tom

[blink138 (Pat)]

hi tom make sure your internal noise reduction is activated on your 550d
pat

[Tom_88 (Thomas)]

The internal noise reduction was turned on, it might be the ISO, it was 3200 for a 20 second exposure at f/3.5. Bit of ovekill perhaps.

I'll try a lower ISO tonight, any ideas about the RAW stacking?

[CapturingTheNight (Greg)]

Hi Thomas,
I'm sort of working through a similar issue with DSS and RAWs with that vertical strip you mention. I don't have an exact answer for why but from my experimentations I think there are a couple of things that are going on. DSS stacks RAW images from my Canon 1000D without any problems at all but when I do similar images with my 60D I get that vertical strip with the RAW image stacks. Stacking the jpegs (I shoot in RAW + jpeg at the same time) is generally fine. This leads me to think that there is an issue with my version of DSS not correctly reading the RAW's from newer cameras, but I have updated to the latest version and it still happens. Another thing it could be is that with my 60D I am generally stacking widefield tracked shots, whereas the 1000D is hooked into my telescope so there are a lot less stars in the frames to stack. Maybe there is an issue with DSS overloading on stars? Sorry I can't help, but if you answer the following questions it might help me work it out. What sort of images are you trying to stack (widefield, deep space objects, etc)??? and have you tried stacking the RAW's versus the Jpegs from exactly the same image sets??
Cheers
Greg

[Tom_88 (Thomas)]

That sounds famaliar about the version of DSS, I seen somwher that there was an addition to DSS that supported RAW images for newer cameras or something along those lines.

The photos are widefield shots through an 18-55mm lense on a tripod. DSS stacks the JPEGs with no dramas even though the camera is on a fixed mount, so I would assume that it would also have no issues stacking the same in RAW format but the final black strip image has me stuck.

[CapturingTheNight (Greg)]

Just solved it Thomas. After seeing your post I got all motivated and had another try. It is def. DSS not reading the newer RAW versions. Download the following link and extract the three files, then open the DeepSkyStacker.exe file and use that version from now on. You should be able to use your RAW files now
http://deepskystacker.free.fr/downlo...r333beta45.rar

Cheers
Greg

[Tom_88 (Thomas)]

It works! Thank you very much! I spent the most of my sunday trying to figure this one out...

[CapturingTheNight (Greg)]

Originally Posted by Tom_88

It works! Thank you very much! I spent the most of my sunday trying to figure this one out...

My pleasure. Been bugging me for a while.

[jjjnettie (Jeanette)]

Deep Sky Stacker Beta is what you need.
As for noise with your Canon 550D, you'll find that once temps start dropping below 10C things will start to improve dramatically. This particular camera doesn't like it warm. Bring on Winter I say.

[Tom_88 (Thomas)]

Thank you also jjjnettie, i'll keep that in mind for sure! It has been cooling right down so hopefully the camera will do the same. I'll post up some pics soon! Any more tips or advice?

[2stroke (Jay)]

Make a cooler box for your camera, this should help out with noise a heap. If your got balls mod it with a TEC cooling and a cold finger now this is where the magic happens at high iso and noise Just do a google search for dlsr cooler box and you will find tons of info, building one is easy and doesn't require modding your camera or voiding warranty. Also try not to use live view and allow a cool down period between shots, this will also help out with noise