Nikon D3100 Gordon Laing, November 2010

Click here to find out about the Nikon D3100's Movie Mode

Nikon D3100 lenses, focus, sensor & drive


The Nikon D3100 has an F-mount which can accommodate most Nikkor lenses, with the DX-format sensor resulting in their field of view being reduced by 1.5 times; so the DX 18-55mm VR kit lens delivers an effective focal range of 27-83mm.

As with all Nikon DSLRs, you’ll need recent lenses to support the full focusing and metering modes. There’s a compatibility chart in the D3100 manual or specification sheets, but just briefly you’ll need a Type G or D AF (including AF-S and AF-I) Nikkor to support all functions including the most sophisticated 3D Colour Matrix Metering II system.


Like the D40(x), D60, D3000 and D5000, the D3100 does not feature a built-in motor required to auto-focus older lenses. These lenses will still work on the D3100, but they become manual-focus only. The D3100 will only auto-focus with AF-S or AF-I CPU lenses from the Nikkor range. If you want autofocus from third party lenses, look for models with built-in focusing motors like Sigma’s HSM series.

Like its predecessors, Nikon omitted the AF motor to save size, weight and cost, and while its absence will frustrate enthusiasts who want to use older lenses, it’s less of an issue for the D3100’s target audience which will mostly buy newer AF-S models.

Nikon's steadily releasing more and more AF-S lenses including a number of new primes. A great complement for a kit zoom is the Nikkor AF-S DX 35mm f1.8 which delivers standard coverage, a bright aperture and very respectable image quality at a low price; see our Nikkor DX 35mm f1.8 lens review for full details. If the lack of a focusing motor really is a deal-breaker for you though, trade-up to the D7000 (or an older D90) instead.

The Nikon D3100 is typically sold in a kit with the Nikkor DX 18-55mm VR lens. The VR stands for Vibration Reduction and provides the lens with anti-shake capabilities which you can see through the viewfinder, although with a longest equivalent focal length of 83mm, any wobbling isn’t that obvious. We found the lens stabilisation was good for around three stops of compensation in practice.


Nikon D3100 focusing

Nikon's D3100 inherits the same 11-point AF system as its predecessor, along with the D5000 and D90. This employs the same Multi-CAM 1000 module with a single cross-type sensor, and the options appear to be identical. As such there’s three main AF modes: AF-S (Single Servo AF), AF-C (Continuous Servo AF) and AF-A (an Auto mode which selects between them depending on whether the subject is in motion – this is the default option). These are selected from the main information display screen, where you’ll also be offered a Manual focusing option.

Unlike many affordable DSLRs which strobe their built-in flashes for AF assistance, the D3100 employs a dedicated lamp – it’s pretty bright, but much more discreet than the flickering flashes of Canon's models.

Support this site by
shopping below

Like the D5000 before it, there’s four AF Area modes: Single Point, Dynamic Area, Auto Area, and 3D Tracking (the latter only available in AF-A and AF-C modes). In Single and Dynamic Area, you can manually adjust the focusing point using the rocker control, with Dynamic Area also considering surrounding focus points if the subject moves. In Auto Area, the D3100 chooses the focus point automatically.

With 3D Tracking, you manually select a focusing point and place it over the desired subject. With the shutter-release half-pressed, the D3100 will then attempt to keep this subject in focus even if you recompose the shot. 3D Tracking also exploits colour information to help track a subject, although obviously if it’s the same colour as the background, the system will become confused. Nikon recommends using Dynamic Area for erratically moving subjects, and 3D Tracking when recomposing photos with relatively static subjects.

We’ve detailed the Live View auto-focusing options on the previous Design page, but just briefly here, the D3100 exclusively relies on contrast-based AF in Live View, with the choice of four modes: Normal Area, Wide Area, Face Priority and Subject Tracking. New to the D3100 over previous models though is the choice of AF-S (Single) or AF-F (Full-time Servo) in Live View, where the latter attempts to continuously autofocus – again we have full details in our Live View section on the previous page.

Returning to the main 11-point phase-change AF system, the D3100 unsurprisingly performs identically to the D5000 and D90 before it. Set to the default Auto Area it generally does a good job of recognising the primary subject and locking the lens onto it, with the active AF points highlighted – albeit with red lights as opposed to the LCD graphics of the D5000 and D90. In Dynamic mode with AF-C, subjects placed under the manually chosen focus point are tracked effectively as they move towards or away from the camera.

Finally, the 3D Tracking option was effective at following subjects moving around the frame or as you recomposed with a static subject. This worked particularly well with strongly coloured subjects which stood out from the background, although as Nikon recommended, it’s best-suited to more leisurely motion. Technologically it’s also fun to watch the active AF point follow the subject around the frame, at least in the area covered by the 11 points, although in this regard Nikon’s higher-end models with their 51-point AF systems are ultimately more impressive.

As with all DSLRs which offer a variety of AF options, it’s a case of experimenting to see which works best for your particular application. But if you’re shooting a subject in motion and can keep it within the diamond area covered by the 11 AF points, the D3100’s Dynamic Area and 3D Tracking modes should keep it sharp. The only caveat is the supplied DX 18-55mm VR kit lens which as we've seen before is neither the quickest nor the quietest focuser in the range. If you demand snappier performance, or something quieter when recording movies, upgrade to a better model.

Finally, an interesting feature inherited from the D60 and D5000 is the Rangefinder option, enabled in the Custom Function menu. This uses the exposure compensation scale in the viewfinder (but not on the main screen) to indicate focus distance while manually focusing. As you approach perfect focus, the scale reduces to just two markers either side of zero. As you’d expect for a camera at this price-point though, there’s no AF micro-adjustment.



Nikon D3100 exposure modes and metering


The Nikon D3100 shares the same exposure modes as its predecessor, although one has been enhanced. The main dial offers the traditional PASM modes, along with direct access to six scene presets, flash off, full Auto (with scene detection in Live View, see screenshot right) and the newly improved GUIDE mode, more of which in a moment; there's no movie mode position on the dial as you can start shooting in any mode by simply entering Live View then pressing the red button on the rear.


The D3100 offers shutter speeds between 1/4000 to 30 seconds with a Bulb option in Manual; Program Shift is also available. Exposure compensation is available in a broader than average range of +/-5EV, but annoyingly – and bizarrely – there's still no exposure bracketing on offer. Normally we'd excuse an entry-level DSLR for only offering three-frame bracketing with a +/-2EV range, but like its predecessor, the D3100 doesn't offer any at all. You can of course just bracket by manually adjusting the required settings, but the absence of any automatic options feels like Nikon being deliberately awkward.

The Nikon D3100 shares the same three metering modes as the D60 and D5000 before it: Spot, Centre-weighted and 3D Colour Matrix II, the latter employing a 420-segment RGB sensor. Like most settings on the D3100, these are adjusted through the main information screen system. Note you’ll need a type G or D lens to deliver distance information for the 3D system, otherwise the D3100 falls back on Colour Matrix Metering II. We found 3D Matrix metering on the D3100 delivered consistently accurate exposures, although strangely the exception was our main real-life resolution composition which always seems to fool Nikon's DSLRs into over-exposing – see our first results page.

Regardless of your shooting mode, the D3100 is a very friendly camera. Like its predecessor, the D3100 has sensibly retained the context-sensitive help system which displays handy hints on the current setting or menu whenever you press the Question mark button. Sometimes you’ll see the question mark blinking in the corner of the screen, in which case the D3100 believes something’s wrong and wants to make a suggestion, such as to use the flash. If only all cameras were this friendly.

The D3100 however goes one step further by inheriting – and enhancing – its predecessor's innovative GUIDE mode which proudly has its own position on the main mode dial. Through a friendly graphical interface and series of questions, the GUIDE mode determines what kind of photo you want to take and then chooses the optimal settings to achieve the desired effect. It also teaches you as you go, allowing you to grow with the camera.


Like the D3000 before it, the D3100's GUIDE mode starts with three main options: 'Shoot', 'View / Delete' and 'Setup'. Choosing Shoot presents three options: 'Easy Operation', 'Advanced Operation' and 'Use a timer / quiet shutter'. In the Easy Operation section the D3100 lets you choose from what are effectively nine scene presets: Auto, No Flash, Distant Subjects, Close-ups, Sleeping Faces, Moving Subjects, Landscapes, Portraits and Night Portraits. Some simply recognise that in the specified situation the flash or AF illuminator would either be unwelcome or redundant, so prevent it from operating.

The first difference between the D3100 and its predecessor though is once you select the option to 'Start shooting', the D3100 asks if you'd like to use the viewfinder, live view or record movies.

Things get more interesting in the Advanced Operation section, where you’re given the choice of 'Soften Backgrounds', 'Bring more into focus', 'Freeze motion (people)', 'Freeze motion (vehicles)' or 'Show water flowing'; the latter and 'Bring more into focus' are new to the D3100. As you might expect, these options become friendly interfaces for using Aperture and Shutter Priority. 'Soften Backgrounds' and 'Bring more into focus' automatically switch the D3100 into Aperture Priority mode, and let you choose an f-number, with the camera explaining that lower f-numbers blur the background.


Similarly 'Freeze motion' or 'Show water blurring' switch the D3100 into Shutter Priority mode and allow you to adjust the shutter speed, with the camera advising shutter speeds should be chosen to ‘freeze’ motion. The people and vehicle options advise using shutter speeds of at least 1/200 or 1/1000 respectively.

What makes all these advanced options easier to use than its predecessor though are small thumbnail images which change to preview the effect of the current settings. Reduce the f-number on the 'Soften backgrounds' setting and you'll see the background gradually become more blurred as the person in front of it remains sharp. Similarly in the Motion settings, you'll see the subject gradually become more blurred as the shutter speed is reduced. This is really helpful stuff.

If you try and choose too fast a shutter speed or too small an aperture for the available light, the D3100 warns the subject will become too dark. Rather than automatically bumping up the sensitivity though, the D3100, like its predecessor sticks with a fixed value and ‘lets’ you change it manually later, which seems less helpful than it could have been. Once you’ve chosen the desired shutter or aperture value, the D3100 then asks if you’d like more settings, or start shooting. The more settings option lets you adjust the picture control, exposure compensation and flash compensation on a first page, followed by flash mode, release mode and sensitivity on a second page, each accompanied by thumbnail images showing how each might be used. Interestingly the AF mode option of the earlier D3000 has been removed.

The Timers / Quiet shutter section simply shows a photo of the top of the camera and tells you to turn the release mode switch to the desired position – yeah, thanks for that. Likewise, returning to the first page, the View / delete and Set up options present simplified versions of the normal menu sections for each.

In use, the Guide section certainly presents a beginner-friendly interface to operating the D3100, and we can imagine many first-timers leaving it on this mode most of the time. But it’s certainly not 100% foolproof across all the options. As mentioned above, the Advanced modes can let you dial-in an aperture or shutter speed which will result in under or over-exposure, and while the D3100 will warn you of this, the Guide mode won’t automatically adjust the sensitivity to solve at least some of these situations. For example if you choose to Freeze motion in the Advanced mode with too fast a shutter speed for the available light, the D3100 simply says the image will be too dark, rather than increasing the ISO to compensate, or at least suggesting it. A shame since the D3100 has its new Auto ISO option in other modes to get round similar problems.

We're dwelling on this point since the stumbling-point for most beginners when first trying shutter and aperture priority, is getting an exposure that's too bright or dark. Many understand that a big f-number will bring lots into focus and a quick shutter will freeze fast action, but they may not realise why shooting at f22 or 1/4000 may result in a dark image. The D3100 is in the ideal position to explain why and where possible even bump-up the ISO to compensate again with an explanation to its consequence. But like its predecessor, it holds back at this point and lets the photographer work it out for themselves.

This aside though, the D3100 remains one of the friendliest DSLRs on the market. The Auto mode works well, the scene presets provide the usual flexibility, while the GUIDE mode allows you to take more control and learn without becoming intimidated by too many technicalities. It's arguably the best DSLR for beginners.


Nikon D3100 sensor and processing

In a major upgrade over its predecessor, the D3100 employs a new 14.2 Megapixel CMOS sensor. This gives the D3100 four extra Megapixels, along with a switch of sensor technology from CCD to CMOS; now the entire Nikon DSLR range employs CMOS technology.

The sensor measures 23.1x15.4mm, a fraction smaller than the CCD in the D3000, but still conforming to the DX standard, so all lenses effectively have their field-of-view reduced by 1.5 times. The D3100 delivers 3:2 shaped images with a maximum size of 4608x3072 pixels, giving the D3100 roughly 800 pixels more horizontally and 500 more vertically than its predecessor – this in turn allows you to make prints measuring 15.2x10.2in at 300dpi, compared to 12.9x8.6in on the D3000.


Images can be saved with Basic, Normal or Fine JPEG compression, or recorded as a 12-bit compressed RAW file either by itself or accompanied with a Fine JPEG. Best quality Large Fine JPEGs typically measure between 5.5 and 6.5MB each, while RAW files measure around 12MB each.

Like Nikon’s other consumer DSLRs, there’s only basic software supplied for converting RAW files – you’ll need to invest in Capture NX 2 or third party software to perform more sophisticated processing. On the upside, the D3100 allows processing of RAW files in-camera, although you can only adjust the resolution, compression, white balance, exposure compensation and the Picture Control.

With a new sensor comes a new ISO range, with the D3100 offering 100 to 3200 ISO in single EV increments with Hi 1 and Hi 2 options delivering equivalents of 6400 and 12800 ISO. An Auto ISO option allows you to enter a maximum sensitivity and minimum shutter speed, and if enabled, will kick-in for PASM modes when the selected sensitivity fails to allow the desired shutter speed. Auto ISO can choose from sub-1EV increments and is the fixed option for the Auto exposure modes. In practice we found Auto ISO regularly opted for relatively high sensitivities around 1000 ISO, even when using the flash for close-range portraits, so if you want to maximise the quality you may want to reduce the upper limit.

Noise Reduction is On by default and applied to long exposures or high sensitivities. Even if you disable it though, it's still applied at very high sensitivities, albeit to a lesser degree.


Image processing duties are carried out by Nikon’s EXPEED processor. White Balance can be set to Auto, Incandescent, Fluorescent, Direct Sunlight, Flash, Cloudy, Shade or a custom preset. The D90’s manual entry of colour temperature is not available here, but its impressive choice of seven Fluorescent sub-categories remains present, as do the fine tuning facilities for the other presets.

Like other recent Nikon DSLRs, EXPEED automatically removes – or at least greatly reduces – the effect of lateral chromatic aberrations, also known as purple fringing. This correction is applied automatically to all JPEG files whether you like it or not, but not to RAW files; it's very effective in practice as you can see by the absence of fringing in our samples and results images. Canon, please take note and offer automatic corrections of fringing in-camera; the EOS 60D's option to do so when processing RAW files is a step in the right direction, but it really needs to be done automatically on JPEGs.

The Vignette control of higher-end models is still not available in-camera (although it can be applied using Capture NX 2), but the D3100 inherits the D5000's Auto Distortion Control. This applies digital correction for barrel and pincushion geometric distortion, where straight lines can appear to bend outwards or inwards towards the edge of the frame. It would appear to be the same option offered in the Playback Retouch menu, but applied automatically to JPEGs as they’re generated. It’s visually impressive at reduced sizes, but remember such adjustments involve significant pixel-wrangling with potential loss of quality or a slightly cropped image. It's sensibly disabled by default.

The D3100’s Retouch section also offers Perspective control to straighten the converging edges of subjects when the camera’s pointed upwards – although again like Distortion control, this will stretch portions of the image with quality artefacts as a result.

Nikon D3100 JPEG
Active D-Lighting Disabled
Nikon D3100 JPEG
Active D-Lighting On (default)
1/100, f5.6, 100 ISO
1/100, f5.6, 100 ISO

The headline processing feature remains Active D-Lighting which adjusts the tonal curve of images in an attempt to boost darker areas without blowing highlights.

Unlike the D5000 which offered a variety of settings though, Active D-Lighting is either on or off on the D3100. On is the default option, so the one we’ve used in our main Results and Gallery pages, however since it can introduce noise to dark areas, we disabled it for our High ISO Noise results page.

You can see two examples on the left, showing roughly the same handheld composition without Active D-Lighting (far left), and with Active D-Lighting (left). Both were taken in Aperture Priority at f5.6 and 100 ISO, where the camera metered an exposure of 1/100. So both pictures share exactly the same exposures.

It's quite clear how Active D-Lighting has brightened the dark fencing, while darkening the bright blossom and background hills. These changes are reflected in the histograms below each image. While there's still a little highlight clipping, the image with Active D-Lighting is preferred over that without.

More traditional image processing options are applied using a series of six Picture Controls, matching those on the D5000 and D90, with the same degree of adjustment too. The Standard, Neutral and Vivid, Portrait and Landscape Picture Controls all offer adjustment of Sharpening (0-9), Contrast (+/-3), Brightness (+/-1), Saturation (+/-3) and Hue (+/-3), while the Monochrome Picture Style swaps Saturation and Hue for nine Toning and four Filter Effects, the former fine-tunable by seven values. If Active D-Lighting is enabled, it takes over the Contrast and Brightness settings, and if you’re in a real hurry, a Quick Adjust option can boost or lessen a group of settings in one go.


As always we used the default processing option for our test shots – in this instance the Standard Picture Control. As you’ll see in our Results and Sample Images Gallery pages, the D3100’s default JPEG output, like other recent Nikon DSLRs, is fairly restrained and laid back. This delivers very natural-looking images, but we can't help but feel its target audience would prefer something more vibrant and punchy. Fortunately that's easily achieved by tweaking the Picture Controls, or simply selecting the Vivid preset. Better still, shoot in RAW and make the adjustments later.


Nikon D3100 drive modes and remote control

The D3100 offers four 'release' modes: Single frame, Continuous, Self-timer and Quiet shutter release. Rather than use buttons to select them though, Nikon's fitted the D3100 with a rather classy lever on the right side of the main mode dial. This chunky tactile control makes it very quick and easy to check and adjust the release mode – it's an unexpected but welcome upgrade over most entry-level models.


Switch the lever to Continuous and the D3100 can shoot at 3fps with a buffer that can accommodate up to 100 Large Fine JPEGs, 13 RAW files or nine shots taken in RAW+JPEG mode. To put this to the test we fitted the D3100 with a freshly-formatted 8GB Lexar Professional 133x SDHC card, rated at Class 6.

With the D3100 set to Large Fine JPEG, we fired-off 50 frames in 17 seconds with no sign of the camera slowing – this corresponds to a rate of 2.94fps. Set to RAW, we managed 16 frames in 5.5 seconds before the camera stalled, which corresponds to 2.9fps. Finally in RAW + Fine JPEG we fired-off 11 frames in just under four seconds, again corresponding to a fraction below 3fps. In each case we shot at 100 ISO and the buffer took around 15 seconds to completely clear.

As such we're pretty satisfied the D3100 delivers its quoted continuous shooting speed of 3fps. The JPEG rate matches that of the Canon EOS 1000D / XS, although that model slows down when shooting RAW. The D3100 is however more expensive than the Canon, so a fairer comparison would be with models costing roughly the same. Nikon's D5000 for instance was similarly-priced at the time of writing, but offered 4fps continuous shooting. While Canon forces you to spend considerably more for models like the EOS 60D to enjoy significantly faster continuous shooting, Sony offers a number of mid-range models with very quick burst speeds which only cost a little more than the D3100.

Support this site by
shopping below

The bottom line is the D3100 may offer a step-up from entry-level DSLRs in many respects, but continuous shooting isn't one of them. Considering it's priced higher than budget models, this is a bit of a disappointment. Three frames per second is pretty basic, and most action or sports sequences will be over before you've managed to fire-off more than a couple of shots. So if action photography is your thing, we'd recommend going for the D5000, or spending a little more on one of Sony's models instead.

Flick the release lever one notch further and the D3100 goes into self-timer mode, with the choice of either two or ten seconds selected from a menu. The five and 20 second options of the D5000 are absent here, as is the ability to take up to nine shots once the countdown is complete.

The final position on the D3100's release mode lever is Quiet shutter release. This takes the photo as normal when you press the shutter release, but doesn't reset the mirror until you let go – so you could press the shutter release to take the shot, but keep the button held until you're somewhere less quiet. Obviously during that time you won't be able to take any more photos.

In practice if you press and let go of the shutter release as normal, you'll notice virtually no difference in this Quiet mode, but by pressing and holding the shutter release, the mechanical sound is slightly reduced – or at least delayed. To be honest though it made very little difference in our tests. Probably the greatest benefit was that Quiet mode automatically switched off any beeps, so it could be a quick fix in certain situations.

As you'd expect for an entry-level model, the interval timer facilities of the D5000 aren't available on the D3100, and neither is the stop motion movie mode; clearly these advanced release modes, along with the different self-timer options are reserved for the D5xxx line and above. And while there is a mirror lockup function, its purpose, like the D3000 before it, is only to clean the sensor.

Like other Nikon DSLRs, the supplied software bundle is also lacking compared to Canon's models. You do get View NX for basic manipulation and RAW processing, but for more powerful features, you'll want the optional Capture NX software, while for remote control using your computer, you'll also have to pay extra for the Camera Control 2 package. In contrast, Canon supplies all of its DSLRs from entry-level to top professional models with its powerful Digital Photo Professional software and the EOS Utility, the latter offering complete remote control over a USB cable.

What you do now get on the D3100 though is an HD movie mode, and we've devoted an entire page to it. So to find out the full details, please see our Nikon D3100 Movie Mode page. Alternatively if you're not interested in movies, find out how the D3100 compares against its rivals in terms of image quality in our results pages and sample images gallery. Or if you've already seen enough, head straight to our verdict.

If you found this review useful, please support us by shopping below!
All words, images, videos and layout, copyright 2005-2017 Gordon Laing. May not be used without permission.

/ Best Cameras / Camera reviews / Supporting Camera Labs