Was just collecting some rgb data on Ngc 7217 and I was just curious; how long does everyone go for each filter when doing an LRGB image?? How much RGB do you think is sufficient to properly bring out good color in galaxies??
clear skies!!!
RGB integration time for LRGB images (mostly galaxies)
Engaging
I just finished the same galaxy and used all 600 sec subs, about 30 of each for the integration (of course about 1.5 times that many were taken before rejects). Of course your f ratio matters a lot. Mine were taken at f 7.2….
Bill McLaughlin · Sep 27, 2025, 01:26 AM
I just finished the same galaxy and used all 600 sec subs, about 30 of each for the integration (of course about 1.5 times that many were taken before rejects). Of course your f ratio matters a lot. Mine were taken at f 7.2….
I am mainly imaging at f7.2 also with a cdk14, I’m thinking I just haven’t been integrating my rgb data enough, I usually do 300 sec lrgb and 600-900 narrowband. I have the rouz astro cdk reducer kit on the way so I’m super excited to see how the cdk performs at f4.7 and was thinking of setting it up so I can use my osc 2600mc pro to collect all my rgb data at once with a quick swap.
now that I have had a chance to use the cdk for a little it’s honestly shocking how much I can notice the difference between my old idk at f6.8 and the cdk at f7.2. You wouldn’t think that would be that much of a difference!!
For galaxies for RGB, you want the skies as dark as possible, but seeing only needs to be average. For luminance, some moon can be out, but you want the seeing to be excellent. Try to find the shortest luminance exposure that works with your camera and scope. Luminance is where you will find all your fine detail.
This TAIC video has a lot of great info galaxies https://www.youtube.com/watch?v=1XBon7x6kio&list=PLgfsCOEP9cRWXnTwKLCHQfuMKGfqboJ8i&index=194
Helpful Concise