Olympus TG-4 Exposure

Saturation & Hue Accuracy
Slightly below average saturation levels with average hue accuracy.

Saturation. The Olympus TG-4 pushes some colors likes strong reds and dark blues, but not as much as many cameras, and it actually undersaturates light green and aqua tones slightly, and yellow moderately. The TG-4's mean color saturation of 104.1% (4.1% oversaturated) is lower than average these days, yet the camera generally produces pleasant colors in its images (when the white balance is correct). The TG-4 does not offer a saturation adjustment, however you can change Picture Mode from the default Natural setting to Vivid or Muted, in addition to Scene and Filter modes. Most consumer digital cameras produce color that's more highly saturated (more intense) than found in the original subjects. This is simply because most people like their color a bit brighter than life.

Hue. The Olympus TG-4 shifts cyan toward blue, purple toward red, orange toward yellow, and yellow toward green by small to moderate amounts, but most other shifts are very minor. The cyan to blue shift is very common among the digital cameras we test; we think it's a deliberate choice by camera engineers to produce better-looking sky colors, and we don't find the resulting color objectionable. The TG-4's handling of yellows and yellow-orange colors is one of its weaknesses: Yellows are rendered closer to a yellow-green, and significantly undersaturated as well. With a mean "delta-C" color error of 4.79 after correction for saturation, hue accuracy is about average. Hue is "what color" the color is.

Exposure and White Balance

Indoors, incandescent lighting
Auto setting produced overly warm results, and Incandescent was too cool. Manual was pretty accurate. Average exposure compensation required.

Indoors, under normal incandescent lighting, color balance was warm and orange with the Auto white balance setting, and results with the Incandescent setting were too cool, with a greenish cast. The Manual setting was the most accurate and fairly neutral. The Olympus TG-4 required +0.3 EV exposure compensation, about average for this scene. (Our test lighting for this shot is a mixture of 60 and 100 watt household incandescent bulbs, a pretty yellow light source, but a very common one in typical home settings here in the U.S.)

See thumbnails of all test images

Resolution
~2,300 to ~2,400 lines of strong detail.

An in-camera JPEG of our laboratory resolution chart revealed fairly sharp, distinct line patterns up to about 2,400 lines per picture height in the horizontal direction, and to about 2,300 lines per picture height in the vertical direction. Some may argue for more, but aliasing artifacts start to interfere at that point. Complete extinction of the pattern didn't occur until about 2,800 lines in both directions. Adobe Camera Raw produced similar results, though with a lot more chromatic aberration and noise at default noise reduction settings. Use these numbers to compare with other cameras of similar resolution, or use them to see just what higher resolution can mean in terms of potential detail.

See thumbnails of all test images

Sharpness & Detail
Images are soft at default setting, though with relatively few sharpening artifacts. Strong noise reduction even at base ISO reduces fine detail.

Sharpness. The Olympus TG-4 produces somewhat soft images as is often the case with this class of camera, though without strong sharpening halos around high-contrast edges that we often see. Edge enhancement creates the illusion of sharpness by enhancing colors and tones right at the edge of a rapid transition in color or tone.

Detail. The crop above right shows high levels of noise suppression in the mannequins's hair, with most individual strands smudged together in areas of low contrast, even at base ISO. This is fairly typical performance for such a small sensor, though. Noise-suppression systems in digital cameras tend to flatten-out detail in areas of subtle contrast. The effects can often be seen in shots of human hair, where the individual strands are lost and an almost "watercolor" look appears.

RAW vs In-Camera JPEGs
As noted above the Olympus TG-4 produces somewhat soft images that suffer loss of fine detail as a result of aggressive noise processing as well as less than stellar optics. Compare a base ISO in-camera JPEG to an Adobe Camera Raw conversion below to see what we mean.

In the table above, we compare an in-camera JPEG taken at base ISO using default settings (on the left) to a matching RAW file converted with Adobe Camera Raw 9.1 using no noise reduction with strong but tight unsharp masking applied in Photoshop (in this case 400% USM with a radius of 0.5 pixels and a threshold of 0).

As you can see from the ACR conversion, you can extract a lot more detail from the TG-4's RAW files than what a camera JPEG contains, however there is quite a bit of noise already at base ISO, which is the challenge when dealing with RAW images from cameras with such a small 1/2.3"-type sensor. The TG-4's RAW images can also be quite soft depending on the focal length and aperture, requiring copious amounts of sharpening which tends to exacerbate noise. You can of course apply noise reduction (we converted with no noise reduction enabled above, to better show you what you'll need to deal with when working with RAW files). Bottom line: You can extract much better detail than the in-camera JPEGs contain with a good RAW converter (especially since the TG-4 provides no control over in-camera noise reduction), provided you're willing to experiment and apply fairly strong noise reduction and sharpening.

ISO & Noise Performance
Fairly typical high ISO performance for a 1/2.3"-type sensor.

As you can see from the above crops, the Olympus TG-4's strength is not high ISO performance, and even at base ISO, a lot of fine detail is lost due to fairly aggressive noise reduction which can't be adjusted. For in-camera JPEGs, you'll want to keep ISO sensitivity as low as possible, as image quality deteriorates very quickly as sensitivity rises above ISO 400.

We're of course pixel-peeping to an extraordinary extent here, since 1:1 images on an LCD screen have little to do with how those same images will appear when printed. See the Print Quality section below for our evaluation of maximum print sizes at each ISO setting.

Low Light
Decent low-light capabilities for its class.

The longest shutter speed supported by the TG-4 is 4 seconds which is rather limiting, however the camera does have some scene modes which work well in low-light, including Handheld Star Light and Live Composite modes, the latter giving you bulb mode capabilities.

The Olympus TG-4 was able to autofocus down to below 1/16 foot-candle unassisted, and in complete darkness with the aid of its AF assist lamp when shooting at wide angle at f/2.0. That is excellent performance, especially for a pocket camera.

See below for test results with the built-in flash.

Coverage, Exposure and Range
A weak flash with narrow coverage, but range is helped by the fast lens.

Coverage. Flash coverage was quite uneven at wide angle, leaving very dark corners and edges in our flash coverage test image, and you can also see some unevenness in illumination vertically as well. Narrow coverage at wide angle isn't unusual, though, and some of the corner darkening is likely from the lens itself. We no longer test flash coverage at telephoto, as it is invariably better, making wide angle the worst case scenario.

Exposure. Using full Auto mode, the TG-4 performed fairly well with our Indoor Portrait flash test producing a well-exposed image, though Auto white balance produced overly warm results. Still, not a bad performance from such a small flash, though the camera did boost ISO to 400 and used a somewhat slow shutter speed of 1/30s to achieve those results. (Slow shutter speeds like 1/30s can result in motion blur unless your subject is reasonably still during the exposure. We'd rather see a speed above 1/50s for flash shots of people.)

Manufacturer Specified Flash Range Test. The Olympus TG-4's flash range is rated at 7.9m / 25.9 ft at wide angle, and 3.1m / 10.2 ft at full telephoto at ISO 1600. In the above shot at the telephoto range, the TG-4 produced a reasonably bright flash target, indicating Olympus' flash range rating is credible. We shoot this test shot using the manufacturer-specified camera settings, at the range the company claims for the camera, to assess the validity of the specific claims.

Print Quality
A good 13 x 19 inch print at ISO 100; and a good 5 x 7 at ISO 800/1600.

ISO 100 prints are good at 13 x 19 inches, which is a reasonably large size for such a small sensor. There is a decent amount of fine detail and pleasing colors at this size, although for critical printing purposes the 11 x 14 inch prints here are slightly sharper.

ISO 200 images are best limited to 11 x 14 inches, which have decent sharpness and color, though not quite as good as ISO 100. Some contrast detail is now lost in our tricky target red-leaf swatch, but it's otherwise a good print overall.

ISO 400 shots are usable at 11 x 14 inches for less critical applications, but in order to pass our "good" rating we needed to reduce the size to 8 x 10 inches here, which exhibit enough fine detail, good color and virtually no apparent noise to make the grade.

ISO 800 images are not bad at 8 x 10 inches for certain uses, but 5 x 7's are the highest size here that we can award our good rating. There's virtually no contrast detail remaining in our target red-leaf swatch, but the print is otherwise usable.

ISO 1600 prints at 5 x 7 inches just pass our seal of approval, retaining full color and exhibiting low noise. Similar to ISO 800, contrast detail is now lost in our red-leaf swatch of fabric, but the rest of the print remains reasonably sharp.

ISO 3200 delivers a 4 x 6 inch print that may work for certain less critical applications, but overall the print is a bit too "scorched" looking and the colors a bit too muted to attain our good seal.

ISO 6400 does not yield usable prints and this setting is best avoided.

The Olympus TG-4 delivers nice printed images at base ISO, up to a fairly large 13 x 19 inch print given the 16-megapixel resolution and the modest-sized sensor of this camera. We had hoped for somewhat larger prints as ISO sensitivity rises, but the 1/2.3"-type sensor size really hinders good print quality above ISO 400, especially if you like printing 8 x 10's. Unless you're content with smaller prints, remaining at ISO 400 and below is a good bet with this camera, and base ISO is quite nice for most purposes.