I am really with Rick on this. If I do any photo editing it's because the camera I have to take the pics with provides a very lackluster representation that is not at all what it really looks like in my tanks.
It really is in the integrity of the seller to properly represent the coral for what it really looks like no matter what the means to get it done.
Anyone could say they don't photoshop and not be lying if they are using a different photo editing program. Or could say the same and just use a color enhancing filter, or set the color enhancement inside the camera. I mean there are a hundred ways a guy could get around saying they are "photoshopping" but if they are lying they are lying. Not to mention the obvious that there are color differences between most monitors and in different brands, wattage, and kelvin of lighting.
The bottom line is that any type of color "enhancement" is wrong, to make a coral look brighter, more colorful or have stronger contrast is misrepresenting the product. But if I was to take what comes out as an 18' photo and cut it down in photoshop to a photo that is 6' and ready for a listing I would still technically be photoshopping.