jeff_grundman

<p>I was never very happy with my 70-300. It often, but not always, seemed soft. I never did any extensive testing to pin down exactly where it failed, I just know it disappointed me often enough that I eventually replaced it. Since I was usually shooting it at 300, not its strong point, and often wished It had more to give, I replaced it with Sigma's 120-400. It is a heavy beast but gives much better results.</p>

<p>I shoot a D7100 and a D600. My wife shoots a D7000. There is no question in my mind that FX is better in low light. The D7000 is slightly older and the D7100 is slightly newer than the D600 yet the D600 easily has a one stop advantage. It is actually more, but "at least one stop" could not be considered controversial by anyone looking at the images.<br /><br />To answer the posters question... If by 'detail' you mean resolution all sensors of the same megapixel value have the same number of pixels. If you print the images the same size, say 8x10, from a 16mpx DX camera and a 16mpx FX camera both images will be at the same resolution.<br>

If by 'detail' you mean something else then newer tends to be better, and the glass is going to tend to matter more than the camera.</p>

<p>I know I am moving out of the price range you are thinking of but I would recommend the D600. You will get superior low light performance and be able to take better advantage of wide angle lenses for your landscape work. There is the D610 of course, but I expect that because of that the D600 will be a real bargain by the first of the year.<br /><br />I also do nature photography and for me the D600 & D7100 make an awesome team. Yes, I do get sensor spots, the problem is real, but cleaning the sensor is not especially tricky once you get past the intimidation factor and for the way I shoot it is not like it has to be a daily ritual. I have shot something like 12,000 images on my D600 and only cleaned the sensor twice.<br /><br />I would have a very hard time moving from the D7000, which my wife shoots, to a lower end D5xxx series camera. We had a D5000 a year ago and while it was a very nice camera it really wasn't well laid out for serious work. Most of the same tools are there, but digging through menus to get to them is a real mood killer. That said the swivel screen is awesome. Laying in the mud on low angle shots to see what you are doing is also a mood killer.</p>

<p>Any contact with water. My D600 became partially unresponsive after shooting a wedding in the rain. In my case it behaved as though the shutter button was half way down all the time. I pulled the battery, packed it in silica gel in a warm spot for a couple of days and the problem cleared up.<br /><br />I would at the very least try pulling the battery for half an hour to completely power it down, and see what happens.</p>

<p>Sam, it doesn't matter what I find acceptable. Take some test shots and see what you are willing to put up with. I just got a D7100 last night so I have not answered this question for myself yet. <br>

With my D600 I start to be concerned when I exceed 800 ISO but I will shoot at 6400, and even above, rather than not shoot at all, but I know there will be compromises. I have not proved it out yet but due to the much smaller pixels of the D7100 sensor at best I expect it to be no better than the D600, probably a little worse.</p>

<p>I shoot the D600. I find the 9 point focus to be more reliable in AF-C. Lots of good advice above, but this is one more thing you could play with.</p>

<p>Something else to consider... The D7000 has a built in focusing motor. The D5200 does not. If you have any "D" series lenses they will not auto-focus on the D5200. </p>

<p>The focus does not look too bad to me, given the resolution. What are you unhappy with?<br>

Are you using single point focus or are shooting in area mode and letting the camera figure out what to focus on? The D90 also has a 3D focus mode that I have heard is less than perfect. I have not used it so I don't know its quirks. <br>

I also don't use AF-A so I am not that familiar with it. AF-S focuses when you press the shutter button half way down and then locks the focus at that point until you release it or take the picture. If your subject moves closer or farther away before you press the button all the way down to snap the picture then they will be out of focus. AF-C is supposed to focus continually so that subject movement is tracked, but it is not always as accurate as AF-S. It is usually quite good though.<br>

The depth of field seems quite high here. What aperture are you using? With very small apertures you loose sharpness to diffraction. Is that a possibility? Are you using a poor quality lens? Shutter speed too low?</p>

<p>My D600 has more dust issues than my wife's D7000. Perhaps because she has an all-in-one 18-300 that she rarely changes while I am constantly swapping lenses in the field. Perhaps because the D600 is more suseptable to dust issues. I don't know. What I do know is that I am aware of it, so I am able to keep it under control without it being a major issue. If I had it all to do over again I would still buy the D600. It is a fantastic camera for the money.</p>

<p>There is also angle of view to consider. The DX gives you 1.5 times the reach of a full frame sensor. That may matter to you for shooting sports that aren't up close and personal. What you may be used to seeing with 300mm glass will suddenly look like 200mm glass.</p>

<p>I bought a D600 that ended up having the oil spot issue. It was only visible on images with large uniformly light toned areas and I easily fixed those in Lightroom with the spot healing tool. It was annoying but not really a big deal. After a couple of thousand images, most of which had no problem, and when I was confidant that it had splashed around all of the oil it was going to, I got a full frame sensor cleaning kit at the local camera store, cleaned the sensor and have had no problems since. Yes, the oil problem is real and it does happen on at least some D600s. It is not however as big a deal as everyone seems to be making it out to be. If I had it all to do over again I would buy the D600 again in a heartbeat! It is an unbelievably good camera for the money.</p>