ASICap fits and Tiffs are greyscale, but PNGs are RGB and look distorted?

JasonMathias

Im using the colored camera ZWO533 with the ASICap selected on moon mode. I am shooting in R16 and so it should be in full color. The display on my computer screen looked perfect and full of color. But after I was done shooting and pulled the fits into the fits viewer to see how they came out it was grey and no color, or completely weird looking like too dark with a magenta effect?. When I saved as a Tiff to look at it in photoshop it says greyscale and looks good but grey. But when I save the fits as a PNG it says RGB and has some color in it but barely as it still looks almost grey and looks way darker and funky than the tiff? When I increase saturation the color barely comes out at all. When I used ASILive I didnt have this problem and had nice full color. Please Help! How can I get color back in my images of the nice red eclipse from last night like how it looked on the display?

These are my settings:
[ZWO ASI533MC Pro]
Auto Exp Max Exp = 30000ms
Auto Exp Max Gain = 300
Auto Exp Target Brightness = 100
Bin = 1
Brightness = 1
Capture Area Size = 3008 * 3008
Colour Format = RAW16
Debayer Preview = ON
Debayer Type = RGGB
Exposure = 100ms
Flip = None
Gain = 375
Hardware Bin = OFF
High Speed Mode = OFF
Mono Bin = OFF
Raw Format = ON
StartX = 0
StartY = 0
Temperature = 32.8 C
Timestamp Frames = OFF
USB Limit = 100
USB Port = 3.0
White Balance (B) = 95
White Balance (R) = 52

johnpd

I also used an ASI533MC Pro to take a number of images of the eclipse controlled by an ASIAIR Pro.

What was the F/Ratio of your scope or lens. I asked this because your gain seemed rather high, but your exposure was shorter than mine so that might have been ok.
++ I was using a 5" refractor @ f/4.8, Focal Length of about 620mm. I used Unity Gain (100) and the best image I got was at 1 sec. I might have gone slightly longer.
When I viewed the FITS images in the ASIFitsView program, it also ended up very strange, although what appeared on the screen was not that bad. ASIFitsView displayed a very washed out image. When I loaded it in GIMP, it was almost all black. I am not sure how to process it using that program. When I saved the .TIFF and looked at that, it was also almost all black.
When I load it into my favorite image processing program, i got very different results. I use Affintiy Photo which has a number of astronomy-related image processing features included in it. Affinity Photo will directly load and process .FITS files. No conversion needed. You need to go through the following steps:
a. When first loaded, it asks to verify the FITS Bayer pattern (RGGB).
b. After applying that, you need to merge all visible layers that exist for the image. Affinity Photo automatically generates a "Curves" and "Levels" adjustment layer for any FITS image.
c. Next you select the "Astrophotography" > "Remove Background" Filter option. There will be a small circle in the middle of the image. Move that off the Moon and click "Sample at handle position". Now you image will look more normal.

So there is something strange about how ASIFitsView is seeing these images. I have attached four images: (1) What I see in ASIFitsView with my 1.0s image, (2) Initial view after loading FITS image into Affinity Photo, (3) Initial screen of image before applying "Astrophotography" > "Remove Background" filter, and (4) the image after applying the filter. That is a big difference from what the other software programs are giving you. I don't know if Photoshop has such an option. Affinity offers a 30-day free trial. It is very Photoshop-like in its functions and only costs $55 if you like it.

JohnD