Hi. I purchased a Nikon D5100 in October 2012 (Sam's Club online), according to the manual it should take about 660 pictures on a full charge. Every since I've had this camera, I've only be able to take about 150 pictures and then I get a low battery sign. I purchased a back up battery soon after buying this camera because I was afraid the battery would ran down. It's already been sent to Nikon once and it's currently there for the 2nd time. The first time I used it after getting it back from Nikon (which they said there was nothing wrong), with the battery fully charged, I took 178 pictures, then low battery and that was it. This is my first DSLR and one of the reason for buying was for longer battery life and good quality pictures. I'm happy with the camera and the pictures it takes but I can't understand why it won't take the # of pictures mentioned in the manual or even half that amount. I basically keep it on Auto and use the eyepiece to take pictures. I'm REALLY hoping Nikon will take a closer look this time and find the problem. Other Nikon users I've talked to are like "I can't even remember the last time I charged my battery". Are you kidding me! I wouldn't even leave the house without my backup battery. Please help, I don't want to be disappointed but... and I sure can't take the chance (nor the money) and buy another Nikon and run into the same problem. Also, this happens no matter which battery I'm using or which lens, still the same problem. Thanks!