The Nikon D3100 is a great little hybrid digital SLR camera for users who haven't used an SLR before. It's relatively small, has a comfortable body, and includes some built-in guides that can help you take the type of shot you're after. These guides can help you learn the effects of different aperture and shutter speed values, which will allow you to one day successfully wrestle with the camera while it's in full manual mode. The other neat thing about the D3100 is that it can capture impressive Full HD (1920x1080) video.
The Nikon D3100 does a great job of capturing both still images and videos, and because you can swap and change lenses, you can be as creative as you want to be. In kit form, the D3100 ships with a decent 18-55mm zoom lens, but you will want to get something better eventually. It also ships in dual-lens kits.
The 18-55mm is a lightweight lens that suffers from excessive barrel roll, so straight lines invariably end up looking skewed when taken at a wide angle. But the overall picture quality is good, as the lens has little to no chromatic aberration and it can also be used effectively for close-up shots. It's easy to focus in manual mode and it produces a nice background blur for portraits and macros.
You can choose from 11 focus points very easily when focusing. In this picture, we planted the focus on the duck's beak.
The camera has a 14.2-megapixel CMOS sensor takes very good photos considering it's only an entry level SLR. Photos will look clear and vibrant by default (you can change the colour setting in the camera to make them more saturated if you wish) and you can even use a high ISO sensitivity without noticing any discolouration and grain in your photos.
In fact, images look great, even when shot at ISO 3200, and this is a big improvement over the previous version of this camera, the Nikon D3000. Only when viewed at their native size will you be able to notice any softness around the edges of images and some slight discolouration. We don't think you'll have any problems at all printing out your images at A3 size or bigger.
The high ISO performance of the D3100 is excellent.
Photos can be framed either through the optical viewfinder or by using LiveView mode. There is a little timer in LiveView mode that tells you when the mode will be switched off. This serves a couple of purposes: it helps you conserve battery life, and it helps keep the camera from overheating. It should be noted that in LiveView mode shots don't always come out the way they appear on the screen, especially if you are dictating the exposure settings yourself.
Another little annoyance is that the screen doesn't swivel rotate, so you can't flip it around to capture self-portraits or shoot at awkward angles. It's not a feature that's common in entry level digital SLRs though, so we're not too mad, the competing entry level digital SLR from Canon, the EOS 1100D, also lacks a swivelling screen.
In terms of shot-to-shot performance, the Nikon D3100 feels reasonably crisp, but it has one of the softest sounding shutters we've ever heard. Instead of a crisp click, the shutter produces a more electronic sound that is somewhat similar to a vinyl record being quickly scratched back and forth. Focusing with the 18-55mm is sometime slow, but we expected that, especially in low-light conditions.
We do love the fact that it is very easy to change focus points by just using the thumb pad on the rear of the camera's body. There are 11 points to choose from. The camera can also focus automatically when taking video, which is great, though sometimes it selects an unintended focus point. We prefer using manual focus in movie mode, especially as autofocus makes a lot of noise and there is no option for attaching an external microphone.
Even in low-light conditions, the Nikon D3100 works well.
The layout of the buttons is logical and it includes a single thumb dial so that you can quickly change the shutter speed and aperture values. To change between the values in manual mode you have to press the +/- button next to the shutter.
One thing that's lacking is a dedicated button for changing the ISO speed. In order to change the ISO speed you have press the 'i' button at the bottom-left corner of the camera, which then displays all the settings, and then you need to press it once more to actually alter them.
A slider is located under the mode dial of the D3100, and it allows you to quickly switch from single-shot mode to burst mode, timer mode or quiet mode. Quiet mode allows you to take a picture while making the least amount of noise possible. When you take a picture, you can halve the sound the camera's shutter makes, which is useful when taking photos of a sleeping baby or a pet, for example. You can hold down the shutter and move to another location before letting it go. The speed of the camera in burst mode is adequate; and we were able to get around 2.8 frames per second in our tests.
While the D3100 is designed to be easy to use and to actually teach the user a little bit about how to use a digital SLR camera, we feel that the interface could stand to be a little better. In particular, the scene modes on the mode dial are only indicated by their icons instead of labels, so many users won't know what they mean. We also wish the screen was a little better, as it sometimes does not reflect accurately what you have taken.
But apart from that, it's hard to fault the Nikon D3100. Its picture- and movie-taking capabilities are top-notch and the camera feels small and comfortable to use. We would recommend it to a user who wants a manageable digital SLR to take with them on holidays, or indeed to anyone who wants to know more about the art of photography and what effect apertures and shutters can have in different scenes.