I have a thread in the Nikon forum called "Nikon D7000 tips". Some of these tips and suggestions will work on many different models and brands of cameras. I invite you to read the thread and see if there might be something in it that you did not already know. I am cut and pasting my last tip here also because it might help some of you night shooters with your pictures. So take a look and see if you might benefit from it, Jeff
Nikon D7000 tips
Having trouble with auto focus in low light
Ever go out at night and the light is so low you just can't get your camera to focus! Well I have a simple answer.
Here is what you do
I have had this happen a few times and have found that with your camera on single area focus point activated on the spot you want to focus on, if your camera will not focus, all you need to do is buy a laser light pen at Walmart for about $2.50 and point it at the spot that your focus point is on and the camera will lock on followed by the little green light in the viewfinder magically appearing and your shot will be in focus. This of course is for stationary subjects taken in dark surroundings but it will make your camera lock on to the focus quickly.
Remember to not point the light in people's or animal's eyes and it is probably not a good idea to point it at the sensor of your camera.
NOTE: I normally wait several days in between posting tips but I am doing this one ahead of time due to getting ready for my trip to Disney World at the end of the week. Merry Christmas to everyone and a Happy New Year, Jeff