Last night I had the opportunity to push the D3100 to the limit in some low light, hand held shooting. Let me just say that I am very impressed with how the camera handled shooting in low light, with the 18-55mm F3.5-5.6G VR kit lens no less! I took the photo below while shooting through the widow of a car. The VR sure kept the image stable on the bumpy road!
Myst In The Sunshine Valley
Later in the evening I stopped at a mountain resort and took some more images, most of which were at ISO3200. Shutter speeds were often no greater than 1/25s, like in the image below, but the VR in the 18-55mm VR insured that I got sharp images for the most part. The images themselves turned out rather well, and with a little noise reduction they aren't overly noisy either!
As you can imagine from the image above the weather was very cold, but the D3100 kept on going, I didn't even notice any slowness in auto focus or a reduction in battery life. I wasn't shooting outdoors very long mind you (10-15 minutes). You can look at more sample photos from the D3100 in the sample gallery.
Like most entry level cameras the D3100 has only one cross type AF sensor in the middle of the frame and that was the most reliable AF point in the low light I was shooting in, but for the most part the other AF points worked just fine. There were a few times that I had to try focusing more than once when not using the center AF point, but considering the subjects that I was shooting, all stationary, that wasn't a problem. For moving subjects, I'd stick with the center point. I haven't run into any issues with the D3100 so far, and to be honest this little camera has performed far better than I expected it to. In terms of auto focus the D3100 is a big step up from the likes of the D40, D40x and D60.
On a side note, I've got to say that I'm impressed with the 18-55mm VR, which has been bashed by a lot of people, but I think it performs rather well considering the price is less than $200. During the last few weeks I haven't be able to do much outdoor testing with the D3100, due to heavy rainfall, so last night was a real treat. I was thinking about delaying my full review of the D3100, but I think I'll aim to finish the review next week.