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Noise Reduction Tools Color Correction on Saturn Image Mike Askew Photography
Saturn and Too Much Blue
On April 8, I got a nice image of Saturn. It was my first use of a new Televue 4x Powermate, and at f40, the image turned out quite well. I posted a link to it on the Yahoo! CGE Uncensored group. Lyndon Thompson commented that the sky was a little too blue (it was very blue in the original) and Mike Dodd noted that the histogram had some strange characteristics. I went back and looked at the original and Mike was right -- the blue black point was too low and both the green and red looked clipped at the black point. That led me to try another version of the image
This is the original image exactly as it came out of Registax. Click on the image for a larger version.
Here are histograms of the original image. You can see that the red looks clipped to begin with, green looks normal for an image, and clearly there was a lot of blue in the sky that night. Processing details are included on the photo gallery entry.
Here is the original processing. I took quite a bit of blue out by adjusting the color balance, but it is still quite blue.
This is the reprocessed version. There is much less blue. The green mottling that is in both images is more visible as well. I took Mike's advice on processing this image and slightly reduced the saturation overall.