1) Shoot at the lowest ISO possible. The lower the ISO the lower the noise, and the better quality image. The base ISO of your DSLR is its sweet spot. For most Nikon DSLR cameras, that’s going to be ISO 200. Leave it there if you can.
2) Shoot tight. Frame your shot to fill the frame. Maximize those pixels. When you fill the frame with your subject, you get more image to work with. When you don’t shoot tight and have to crop, you lose resolution. When you fill your frame with your subject, you get the maximum resolution which translates into the best image quality you can get out of your DSLR.
3) Use the best glass you own, and know where the sweet spot is. Where is your lens sharpest with the best contrast and color characteristics? You should be shooting at that f-stop, or as close to it as possible. Know your lens and use it to its maximum potential.
4) Perhaps the most important of all, light your shot properly. Whether you’re using speedlights off camera, or more powerful lights like Alien Bees, spend the time to make sure your lighting is perfect. Lighting is perhaps the single greatest variable that can make or break a shot. You can get an incredible image from a small point and shoot like the Canon G10 if you light it properly. Lighting is the single biggest factor in levelling the playing field between crop sensor DSLR cameras and full frame DSLR cameras. Lighting is everything!
5) Shoot RAW to maximize image quality. If you’re not already shooting RAW, start now! There’s just no comparison between RAW and JPG. When it comes to maximizing image quality, RAW is where its at, not to mention all the additional benefits of RAW like overexposure recovery, white balance correction, and on and on. There are times when shooting JPG is fine. This isn’t one of them. When you’re looking to maximize image quality, shoot RAW.
6) For that little edge… to get that little smidgeon of image quality… develop your RAW image using your camera’s own RAW processor. If you shoot Canon, use DPP. If you shoot Nikon, use NikonView or Capture.You’ll almost always get a little better image. Nothing earth shattering, but it’s usually enough to be noticeable, if ever so slightly.
Follow these tips and you’ll find your images from your crop sensor DSLR are indistinguishable from those of a full frame DSLR camera. Not only that, you’ll find your images are just better all around. You might just surprise yourself at how good they are.