People who read this know that I shot almost exclusively with a Nikon D700. Some people think it is out of date. I find it to be a tank and shoots in all conditions and give great images. Many of the problems people seem to have with image quality seems to be me is the person with the camera. Many times they want to use it as a point and shoot. You can but why? Some on the internet say to shoot jpg as raw is not necessary and takes up too much space. Sorry I totally disagree. I shoot RAW in the field as it can make up for a shoot that was spontaneous and not well exposed. Yes the file size is large but storage is cheap and one rule applies. If it is not a good shot delete it. Lightroom 5 and the new Nikon NX-D makes correcting the images shoot in haste easy. If you are going to call yourself a photographer get the tools to be one.
The question comes up about shooting DX lenses on an FX camera. I have one DX lens left from my D300 set of lenses. The slide show with this article shows the quality you can get. Make no mistake about it they are good but not great. With the D700 and others there is a setting on the shooting menu called image area that allows you to set the camera to automatically go to the DX mode when using the lenses or stay in the FX mode. I shoot in the FX mode. One of the attached images shows how that works with my lens in the wide angle portion. It the vignette clears when zoomed. I personally like the FX pixels for my images as they do seem to be better than the DX version. I do crop out the area I want but doing it from an FX image even with the round corners seems to be better resolution than the ones shot directly in the DX mode. You can also set up the FUNC button to switch between them if you feel the need.
The images turned out pretty well for the test. I am also including a couple of shots of the area that I was in a while back. The creek bed has a ledge in it that drops about 8 inches or so and a pretty good angle into the water. This is after a flash flood so it is pretty raw. You can see there is a big hole there so you need to be sure of the vehicle you are driving. This is not a place for a standard car of even a low sitting truck. With the angle of the entrance to the creek being as steep and high as it is ground clearance and angles of approach and departure are pretty important. I put the one image shot out the window while sitting in the middle of the hole in so you could understand the angle of attach and departure with the next shoot. It looks crooked but it is shot with the jeep going up the incline. You can see the mirror in the upper right hand corner of the image.
For those who might want to know the Angle of approach is the angle of a line from the front tire where it meets the ground to the bottom of the front bumper and likewise for the rear tire and bumper which is called the angle of departure. In the world of off road driving these are pretty important.
If you are going to places like these photos at least know the two of them. They will be listed with the vehicle specs. My Jeep Grand Cherokee an approach angle of 37.3 degrees and a departure angle of 28.3 degrees without modifications. Also if you add a trailer hitch do not add a bolt on that is below the bumper, it will kill the angle of departure on a jeep. The factory and some aftermarket trailer hitches go through the bumper itself. That allows you to keep the factory angle of departure. That should answer why I drive a Jeep.
If you already have DX lenses and are thinking about an FX body you can have some pretty good results with them. I am not sure about some of the other manufacturers as I have heard stories you cannot use their smaller sensor lenses on their full size sensor cameras. You will need to check that out based on what camera system you use. You can save some money using the DX lenses instead of the FX lenses but you will suffer in quality in most cases. However, in some cases proper shooting and post work can help eliminate some of the quality issues if you take your time and do them right. I personally am considering another D300 type camera as for wildlife the crop factor does allow me more range than the FX sensor. I may not keep the DX lens I have as it is a mild WA Zoom and I think a better option is the FX wide angle for now.
I hope you get out and shoot more. If you do not have a vehicle that can get through this type of situation you can always park it and walk in. Flooded creeks are another story and those you stay out.
Note in the last image of the slideshow that the mirror of the jeep is in the upper right corner of the jeep.