Re: Pelican Nebula and M33
Robert Chozick <rchozick@...>
Thanks Stuart. I think we have had this discussion before. I do use Photometric Color Calibration in PI. I pre process in Nebulosity (I am a Mac user) then I go to PI and use SCNR to remove green, Photometric Color Calibration and DBE. Then I go back to Nebulosity to use its Digital Development for its final stretch to a 16 bit Tiff for Photoshop. Then I finish the rest of the way in Photoshop. I have attached what M33 looked like when it went to Photoshop:toggle quoted messageShow quoted text
I did a quick processing in Photoshop without the galaxy color change described below. I just took a bit of green out.
When I do galaxies I use Curves in Photoshop to bring up the red in the core and blue in the arms. These are slight adjustments at specific points with the opposite color being reduced where the other is increased. I manually play to create which part of the galaxy becomes core and which part starts the arms. I know this is not kosher to many but I am not trying for exact reproduction. I think of it as art more than science. In the end I am not trying to get the exact colors just what looks nice to me. I do think I overdid it the effect on this one.
Again the version I posted tonight
I did M33 a while ago without doing the color correction. This one was LRGB plus a good amount of Ha.
I intend to get a lot more subs of M33 and also adding Ha. The one I posted tonight was really only meant to be a test of the new camera.
On Aug 1, 2020, at 8:09 PM, Stuart <stuart.j.heggie@...> wrote:
Robert, both of these shots are really nice! I have been going back and forth on them and wonder about the constraints that OSC cameras put on you for colour. How do you calibrate them for colour? I shoot monochrome with filters and use PixInsight's PhotometricColorCalibration tool which is simply amazing.
I mention this because the M33 shot seems like it could stand a tweak on colour but not an arbitrary one to "make it look like everyone else's". You mention that you use PixInsight. Have you tried that calibration tool?