Well here is the first thing. Whenever you do the color for your background. Actually choose white, or #ffffff. That way you know it's white. Secondly, it's your monitor settings.
Detecto - have you ever had your color vision tested? You may have some degree of color vision deficiency. http://colorvisiontesting.com/ishihara.htm It's not common, but isn't that rare, and only affects males. The above test should really be done with printed cards, but this may be helpful.
I give up. I'm done sitting and painstakingly imaging all of my coins, editing them for proper color and luster, cropping them, etc.
I took those tests before, I have good vision. It wasn't me, it was my monitor being off. I reset my monitor and now I can see it.
Well this morning I was feeling optimistic. In auto mode, it kept overexposing my images, causing them to be very washed out. I was using a slower shutter speed, but that still did not work like I wanted to. So I went into the menu and lowered the exposure on the camera. It's not bad. A little shadowy, and part of the reverse is oof.