Slimline

Olympus has increased the resolution at the entry level in its popular 'Tough' series of digicams with the 8-megapixel Mju 850 SW, which has a 3x optical zoom lens. This second-generation digicam confirms the success of the 'Tough' series and present some interesting new updates to previous models. It's the same size, weight and design as the earlier Mju 790 SW model and is available in silver, black or an arresting lipstick pink.

The Mju 850 SW's slimline metal body  is waterproof to three metres, snowproof to -10 degrees Celsius and can withstand a 1.5 metre drop. These characteristics make it an excellent choice for family snapshooters who want to take photographs at the beach, in the pool or in the snow. It's also a worthwhile addition to a bushwalker's kit and will suit people who like snorkelling and 'messing about in boats'.

Front view of the pink version.

Rear view in pink.

The 850 SW's  image sensor is the same size as the 790 SW but boasts higher resolution and the same lens and LCD are used in both models. Even the Face Detection and Shadow Adjust functions are the same. The 850 SW adds the same Pre-Capture Movie scene mode as the Mju 840 but otherwise has the same features as its predecessor, including four underwater modes (Under Water Snapshot, two Under Water Wide settings and Under Water Macro).

Not unexpectedly, many of the 850 SW's features are identical to those in the Mju 840 (click here for review), as you can see if you compare both cameras' specifications. However, the 850 SW's zoom range is shorter and the wide setting is narrower. Interestingly the speed of both lenses is the same, although the 850 SW's lens can't focus as close.
In addition, the 850 SW only offers ISO-boosting image stabilisation. Like the Mju 840, the 850 SW include the Olympus TruePic III image processor. It also comes with a MASD-1 microSD card adapter, which allows memory cards from mobile phones to be used for image storage. 

Underwater Shooting
One of the most attractive features of the 850 SW is its ability to be used underwater. To assist photographers, Olympus has provided four dedicated scene pre-sets: Under Water Snapshot, two Under Water Wide settings and Under Water Macro. The first is for taking photographs of subjects at middle distance and appears to set the lens to the wide position. We couldn't see much difference between it and the two 'wide' underwater modes.

The Under Water Macro setting adjusts the lens to the tele position and appears to apply some digital zoom magnification. You can, however adjust the focal length with the zoom rocker but the close-ups we took in our backyard fish pond were all out-of-focus, suggesting that true close-up shooting is not possible with this mode, although it would probably be OK with fish at about a metre from the camera. The best shot we obtained is reproduced below.

With a close focusing limit of 7 cm and a default position of the longest focal length, it is impossible to shoot underwater close-ups in confined areas.

The flash fires automatically in all four modes. Fill-in flash appeared to be relatively well balanced in our tests. ISO is not boosted be default and no filtration appears to be applied to correct for the loss of longer wavelengths underwater. Sample pictures are reproduced below.

Underwater snapshot mode.

Underwater wide mode.

Performance
Imaging performance was not quite as good as the Mju 840, largely as a result of the differences in their lenses. Although both cameras turned in almost identical colour reproduction graphs, Imatest showed resolution to be below expectations with a significant difference between centre and edge resolution. This difference increased as sensitivity was raised and grew greater from ISO 200 on, as shown in the graph below.

Lateral chromatic aberration was severe and we found strong coloured fringing in many outdoor shots, particularly at the edges of frames.

 
Both coloured fringing and edge softening are shown in the above enlarged section from an outdoor shot.

Digital zoom performance was better than average and close-ups taken out of water, using the macro and super macro settings produced good results. The white balance, panorama and face detection functions were similar to the Mju 840.

The flash required at least ISO 200 before it could illuminate an average-sized room and flash exposures appeared to be generally about 1/3 stop under-exposed. We also found the anti-shake function was not particularly effective at controlling either camera shake or subject movement in dim lighting.

We measured a consistent average capture lag of 0.5 seconds, which reduced to 0.1 seconds with pre-focusing. Shot to shot times averaged just over 3.5 seconds, extending to almost six seconds with flash. Continuous shooting performance was similar to the Mju 840 but the buffer memory filled after three high-resolution shots. In the standard continuous shooting mode, the camera recorded four high-resolution shots at 0.9 second intervals.

With the high-speed burst mode, shots were recorded at 2048 x 1536 pixel resolution with an interval of 0.13 seconds between frames. It took five seconds to process a high-resolution burst and 6.5 seconds to process high-speed burst.

IMATEST GRAPHS

Centre-of-field resolution.

Edge resolution.

SAMPLE IMAGES

Auto white balance with incandescent lighting.

Auto white balance with fluorescent lighting.

Digital zoom.

Macro.

Super Macro.

Close-up with flash.

ISO 1600 at night.

Image sensor: "1/2.35 type" CCD with 8.5 million photosites (8.0 megapixels effective)
Lens: 6.7-20.1mm  f/3.5-5.0 zoom (38-114mm in 35mm format)
Zoom ratio: 3x optical, up to 5x digital
Image formats: Stills – JPEG (Exif 2.2); Movies – AVI Motion JPEG with sound
Image Sizes: Stills - 3248x2436, 2560x1920, 2304x1728, 2048x1536, 1920 x 1080, 1600x1200, 1280 x 960, 640 x 480; Movies - 640 x 480 at 15/30fps, 320 x 240 at 15/30fps
Shutter speed range:  1/2 sec. - 1/1000 sec. (up to 4 sec. in night mode)
Image Stabilisation: ISO boost (“digital”)
Exposure Compensation: +/- 2 EV in 1/3 step increments
Focus system/range: TTL iESP auto focus with contrast detection; range 50 cm to infinity; macro to 20 cm; super macro to 7 cm
Exposure metering/control: ESP or Spot metering; auto or Program AE plus 24 scene presets
ISO range: Auto, ISO 64-1600
White balance:  Auto, Overcast, Sunlight, Tungsten, Fluorescent (x3)
Flash modes/range (ISO auto): Auto, Red-Eye reduction, Fill-in, Off; range 20 cm to 5.3 metres
Sequence shooting:  1 fps high-resolution; 6.8 fps at 3M output
Storage Media: 14.8MB Internal Memory plus xD-Picture Card slot
Viewfinder: n.a.
LCD monitor: 2.5-inch LCD (230,000 pixels)
Power supply:  Li-42B rechargeable lithium-ion battery
Dimensions (wxhxd): 93.6 x 60.9 x 21.3 mm
Weight: 136 grams (without battery and card)