I'm a beginner on dSLR as well as photography. I've gotten my first dSLR for 1.5 months. It's a Nikon D90. Sometimes after I focused and try to release the shutter, it just didn't work, and I would hear some sounds in my camera. At the beginning I thought it might because I did not have much skill, that was why it did not work. But the same problems just keep happening every once a while. I checked the web and found some people were having the same problem. I'm wondering if there are any chances that the shutter would behave like that? I'm not sure what should I do now, should I send it back to Nikon?