Both were huge, and both needed a lens upgrade to go with it:
* D200, 18-55mm, 55-200mm consumer lenses
* D700, 70-200mm f/2.8, 17-35mm f/2.8 pro zooms (now a generation old)
* D800, 85mm f/1.4, 300mm f/2.8, 24mm f/1.4, 200mm f/4 micro

The D200 combo to the D700 combo gave me a 3-4 stop improvement for indoor volleyball. The D700 to D800 combo gave me amazing sharpness and clarity for portraits and general shooting. I didn't use the D200 for 6 months after getting the D700, and gave it away (it's still in use). I used the D700 only once since getting the D800, so that may not stay with me much longer either. Each jump was so big I couldn't see why I'd still use the older camera or lenses. The 70-200mm f/2.8 VRI is the only lens I still have from the D700 days, and it also only got used once by me (loaned to a friend for a few months, though).

The D7100 and D610 are both 24mp, but the FX sensor is 2.25x the area. If you shoot the D610 in DX mode, the sensor area being used is the same as the D7100, and you get a 11mp image, about 3900x2600 pixels, vs 6000x4000 for the D7100. If you're making an 8x12 print at 300dpi, you need 3600x2400, so the 11mp image is perfectly adequate, and at 200dpi, the D610-DX still lets you easily make an 11x14" print. Meanwhile, the larger D610 pixels give you less noise and better color because each pixel captures more light. With the D7100 image, the pixels need to be digitally averaged to get some of the same benefit. Of course, when you don't need to crop, it's no contest.

Hello everyone. I have been following this site for quite a while, but this is my first posting. I am hoping to get some advice from someone that has both a D600/610 and a D7100. I currently own a D200 and it has been a great camera for me. Love the layout and the feel of the semi-pro body. As long as I do not have to push the ISO too high, it performs great. My main interest in photography is high school sports. The D200 works great as long as there is plenty of light, but for night games under the lousy stadium lights, or inside a gym I am only good up to about ISO 800 before things get too grainy and too much loss of detail. So the question is, a D7100 or D610? Advantages of 7100; better focus system, more reach, slightly faster FPS and of course price. Advantages of 600, better high ISO image quality, which is very important. All my lenses are FX, including my main sports lens, the old but trusty 80-200 AF-S 2.8 By the way, I only shoot sports in JPEG so the buffer is not an issue, and I do crop most of my photos in PP. Thanks for any advice you can give me.

Hello everyone. I have been following this site for quite a while, but this is my first posting. I am hoping to get some advice from someone that has both a D600/610 and a D7100. I currently own a D200 and it has been a great camera for me. Love the layout and the feel of the semi-pro body. As long as I do not have to push the ISO too high, it performs great. My main interest in photography is high school sports. The D200 works great as long as there is plenty of light, but for night games under the lousy stadium lights, or inside a gym I am only good up to about ISO 800 before things get too grainy and too much loss of detail. So the question is, a D7100 or D610? Advantages of 7100; better focus system, more reach, slightly faster FPS and of course price. Advantages of 600, better high ISO image quality, which is very important. All my lenses are FX, including my main sports lens, the old but trusty 80-200 AF-S 2.8 By the way, I only shoot sports in JPEG so the buffer is not an issue, and I do crop most of my photos in PP. Thanks for any advice you can give me.

You guys are getting a little over my head here, but I am trying to follow you. I have always thought that there is a bit of difference between a crop camera, say a 7100 and a full frame camera, say a 600. Both have the same pixel count, but with the sensor on the 7100 being smaller the pixel density is higher therefore the image quality is better than taking a picture from the 600 and cropping it down to the same size. I don't know if that makes sense to you, but that is always how I looked at it. I might be all wet here.