Been playing with my new EOS 60D, and trying out stacking images in DeepSkyStacker. I've had a few trial runs from the backyard, but had a chance to take some shots from a dark site south of Sydney recently. 6x 30s exposures at 18mm, f/3.5, ISO3200, also added 20 darks and 20 bias. No flats so there's vignetting in the first image. I used my Astromaster (there's a handy piggyback mount bracket) to manually guide the exposures with the fine adjustment controls and basically eliminate trailing. That trick works for short focal lengths, but is very hard beyond 40-50mm focal length.
I'm a total novice with DSS, and still not completely satisfied with the results. The images still feel over-processed, and I'm not quite getting the full benefit of the stacking just yet. I couldn't get DSS to accept my RAW images so I had to convert to TIFF in Digital Photo Professional - I think this affected the pixel noise, and I'm experimenting with other settings now to see if DSS does a better job as a result.
[Working directly with individual RAW images has been fun too (some of the editing tools in Digital Photo Professional are great for noise reduction, curve adjustment and vignetting adjustment), but I need to learn how to stack the products effectively.]
First image is the 6-shot stacked image, second image is a processed single image.
Grab the beta of the DSS - that may help with using RAW files for your camera.
For these images, you need a bit more post-processing work, particularly with levels to fix the blackness more.
I took your second shot, and in GIMP, did some messing around, mostly with the levels and contrast. As it was a jpg to start with, I probably went a bit far - starting from a higher quality image will make this work a lot easier.
Hi Chris, thanks for the info and efforts! You're probably right about pushing the black a bit more - bit it's a tricky balance between getting too much of a 'posterising' effect and not having a very rich black. More experimentation required!
Yeah, I think you've gone a bit far with the adjustment, but not easy using the jpeg as opposed to the RAW or TIFF files.
I ran a median filter to smooth the noise on the single (2nd) image and tweaked the levels to darken the black for another version, still need to work on the stacking though!
Looks great Andy well done. Have you downloaded the beta DSS version, that'll solve your not being able to load RAW files. I think we've all been through this, it's like a right of passage.
Thanks Carlos and Chris - I've downloaded DSS beta and got it loading my raw frames. Haven't yet managed to get a significant improvement over using the TIFFs (but only tried once), so will fiddle a bit more with settings. It may well be more of a case of taking longer subs and more images on my next dark site trip... maybe tonight!
I'm still pretty happy with these first images - honestly didn't think I'd capture so much of the dust around Antares and elsewhere!
You're probably right about pushing the black a bit more - bit it's a tricky balance between getting too much of a 'posterising' effect and not having a very rich black. More experimentation required!
