This was taken on a warm breezy night last week with a bit of burning off in the area so not the best conditions. The images after the meridian flip had to be rotated about 0.3 degrees, The scope is level, (something I can control), so I wonder what happened. I also have three questions about the processing side for any willing to offer some advice...
Despite using calibrated blacks and the pixel filter in Maxim, I am still getting a lot of hot pixel trails. Any thoughts?
When using colour balance to tweek colours in PS, is it better to click off the 'preserve luminance' option?
Finally, my last 2 images have had a faint split colour background tint, the left half of the image red and the right blue. Am I pushing the saturation too far?
L 45xmin RGB 20x1min each Stacked in Maxim. LRGB combined and cleaned up in PS
Thats a great looking NGC55 for the trying conditions.
Hot pixel trails? I sometimes get something like that when I use the 'Average' combine method for stacking, when I use median it does not happen.. Thats about all I can offer on that...
When I tweak color balance I click Preserve Luminosity, I dont know if its the right thing to do, but it seems to work for me..
How far are you pushing the saturation? Sometimes saturation tweaks can bring out color noise (depending on how big the tweak is)
Hi Matt. The image looks pretty good to me . You have captured a lot of detail but may well be pushing a bit hard in PS. Hot pixels or pixel trails are a problem but there is not much you can do to avoid them. If your camera is uncooled you may well have a thermal gradient accross the chip which would account for the colour gradient in your image. Processing is the way to remove most of these problems but over doing the processing will introduce problems of it's own such as megga noise etc.
Nice image just the same. Easy to be critical but harder to come up with a solution.
Keep at it.
Alex, I use a Sigma clip so mybe the threshold is too low. Will try a median for the heck of it. I try not to push the saturation beyond +25 but by the time I finish with curves the actual gain my be higher. Thanks
Hi Doug, The DSI II is not cooled and that may well be the problem with the gradient. Re noise I suppose what i really need to do is to go out and get a guider and take longer exposures. Thanks for your input.