Instruction: Extract information from the supporting document to answer the given question.

Input:
Question: Is this lens compatible with the D7100?
Document: Wonderful lens, fast focusing, high contrast, great saturation, light and solid. You get what you pay for.
I wish they had a way to protect this lens, but then it wouldn't be this wide, would it? A wonderful lens. I'm quite happy with it.
I wonder where to use this lens with the new and better lens in 14-24mm F2.8.....this is an obsolete lens by my definition!
Was a grey market lens....I don't buy grey select lenses....sent it back.....Amazon said it was an USA warranty.....was not....S***! S***!
I purchased this item sight unseen. I did not realize that the lens was curved, like a fisheye lens. It will not take a protective UV filter or any other filter.
I have a Nikon d600 and this lens wasn't auto focus, I had to return it. The seller was very honest and kind. I was sad the lens didn't work on a full frame.
I like who this lens will affect the picture though. Not quite a fisheye, but it has a little of that affect to it. great for landscape or tall buildings. Indoors in small spaces also.
This is an amazing lens. I was initially concerned about distortion that bulged from the center out to the edges but the lens does a fantastic job of dealing with it. This lens is one of the best additions to my glass collection.
This is so much better than any other 14mm on the market. As far as the complaints regarding the inability to use a filter, if you just dropped $1600+ on this lens, you should know that a 14mm doesn't allow for filters. This is the greatest ultra-wide out there. Bravo Nikon!
What the sofware did was take that fishbowl look away and make the photo a rectilinear image by reshaping the perspective.If that is true, it's probably what makes this lens such a joy to use. Your angle of view is amazing, and the results give you that rectilinear quality, and it's right in the viewfinder.
Answer: Yes, it will act as a 21mm due to the DX capabilities of the D7100.