I am new here, although I've had a account for awhile. I'm currently shooting with an Aquatica D7000, so I've been reading this thread with great interest since I am currently debating the D7200 vs the D610 or D810. I am mainly shooting wide angle on wrecks in New England. I do travel as well and between bringing my rebreather and the camera, I barely have any room left in my luggage for clothing. So, the comments about the weight/size of a full frame set-up really is giving me something to think about with travel, and even when diving wrecks where I'm going in on a shot line or dealing with a lot of current.
Going to full frame from the D7000 seems like a huge step. Although I have a Tokina 10-17 and a Nikkor 16 mm fisheye, I prefer rectilinear lenses and use a 10-24 Nikon now. It seems like I really would need to invest in new lenses, most likely the 16-35 mm, which would lead to a new dome port and extension ring, increasing size and weight. The cost investment is big and it seems like continuing on the DX path makes more sense.
At the same time, I am drawn to the full frame option like a moth to a flame...
Looking at the D7200 on paper compared to the D7000, the sensor sizes seem very similar. I see the other differences with ISO, effective pixels, autofocus, etc. From what I have read here though, the D7100 was a big improvement over the D7000, and going to the D7200 from my current set-up would indeed be an upgrade.
Does anyone have any additional advice or thoughts for me to consider? Based on the comments and choices others have made, it seems like the D7200 might be the right choice.
I recently switched from the D7000 to the D810 several months ago, and I couldn't be happier. Yes, it is a financial commitment and the gear weighs more (on the surface), but you can't beat the IQ of the D810. I shoot primarily wide-angle in Southern California, and dabble in macro and super macro.
I sold my Tokina (thought I would miss it but I do not), and purchased the Sigma 15mm fisheye and the Nikon 16-35mm. I also invested in the Zen 230mm and Nauticam 140mm domes.
For safety during ripping currents and when you need to be hands-free to shoot a bag, etc., I use the Beneath the Surface Beach Strap System. The clips are always on my BC and strobe ball mounts, just in case I need them. Regardless if you switch to FX or not, I highly recommend the BtS Beach Straps for your set-up. Here is a video my friend and I produced for BtS for that product.
Hope this information helps!