For me, not only was the color, variety, lighting, and texture crystal clear, but I noticed that when I mentally "cut into" the apple, I could see where the pigment from the broken skin cells had been smeared by the action of the knife into the fleshy white interior of the apple. This happened "by itself", I didn't have to try to make it happen. It was at a level of crisp detail that would be difficult to see with the naked eye without holding it very close.
That was the first time I had paid attention to the exact level of detail that appears in my mental imagery, and it hadn't occurred to me before that it might be unusual. Based on what other people describe of their experience, it seems pretty clear to me that there is real variation in mental imagery, and people are not just "describing the same thing differently".