I'm currently using a Macbook Pro OS X Yosemite Version 10.10.4, I own Adobe Photoshop CS6.
When I go to Color Range (Quick Mask is selected) and select a point to the image it shows a transparent red, okay I know that's a mask selection, but when I try to adjust the setting of Color Range it's gray and not letting me adjust anything no matter what I do. I've tried duplicated the original image and it still doesn't work, I've tried mostly everything I can think of. Any suggestions? Here's how the image looks like:
have you ever tried to change "midtones" to "sampled colors"? because its completely normal that everything is greyed out, when you use "midtones" (or any other preset other than sampled colors).