Sigma DP1 Digital Camera Review

After much hype since the first announcement of Sigma's new compact DP1 camera way back at Photokina 2006, the first production models have arrived in the UK shops.

Sigma DP1: Specification

• Sensor: Foveon X3 Direct Image Sensor (CMOS)
• Sensor size: 20.713.8mm
• Ratio Aspect: 3:2
• Resolution: Effective 14.06mp (2652×1768×3 layers)
• Focal length: 16.6 (Equiv: 28mm)
• Lens: 6 elements in 5 groups
• Storage: SD/SDHC/MMC
• Recording mode: RAW (12 bit), JPEG (High, Wide, Medium, Low)
• White balance: 8 settings
• Autofocus: Contrast detection
• Shutter speed: 15sec to 1/2000^th (variable)
• Metering: Evaluative/centre weighted/Spot.
• Exposure modes: Auto, Program/Shutter & Aperture priority/Manual
• Power: Li-ion BP-31, AC adaptor (Optional)
• Weight: 0.25kg (excl. battery)

Sigma DP1: Modes and features
The DP1 sticks to Sigma's philosophy of keeping things as simple as possible with a single control wheel on the top of the camera along with the power button and the shutter release.

There are seven positions on the mode dial which are Program, Aperture priority, Shutter priority, Manual, Auto, Video and Audio record.

The menu system is simple with only Setup, Shooting and Playback as the main headings with the drop downs from these numbering seventeen, fifteen and six respectively. These are scrolled through using the five-way controller in a logical manner.

The most noticeable feature of the camera's simplicity is the fact that it sports a fixed focal length lens, so there are no zoom controls. The focal length of the optic is 16.6mm and this equates to a 28.2mm lens in 35mm format, due to the APS-C sized sensor, a sensor that really makes the camera a specialised one. The reason being that Sigma had one aim in mind when designing the camera, that of Image Quality.

As well as autofocus, the camera can also be focused manually with the use of a small dial at the back of the camera behind the shutter release.

There is a voice recording and video recording capability that, although they are not going to win any prizes, prove useful as a notebook and sketchbook that do not need a week in the menu system to activate.

Sigma DP1: Build and Handling
The build quality is solid with no real pretensions to ergonomics and again, this keeps things simple. All of the controls are positive and easy to get at and the camera is not cluttered. The camera will not switch on with the lens cap in place, as the lens needs to extend some 24mm prior to use and this takes a moment to achieve. The auto-focus takes a further part of a second to achieve a lock, but once at that point the shutter release is almost instant. There is no provision for a cable release, with a two stage self timer the only means of triggering the camera from afar.

The 2.5in LCD screen, sporting 230,000 dots, is adequate and doesn't swamp the back of the camera, leaving plenty of space for the other controls and room to operate them. There is an optional optical viewfinder, VF-11 available to fit in the hot shoe should you wish to acquire it. Being a spectacle wearer, and the accessory having no dioptre adjustment, I did not find it particularly helpful, which is a pity.

Sigma DP1: Flash Options
The DP1 is fitted with a pop-up flash unit needing a press on a small but sturdy catch to enable it.

With a guide number of 6 (ISO100/m) it's useful if not that powerful and a separate, dedicated flash unit EF-140DG with a guide number of 14 (ISO100/m) is much more useful. Exposures using either system are pretty near spot on, so well done Sigma.

Sigma DP1: Performance
This is the area that Sigma have really aimed at with this camera. Not so much in the area of speed, the real performance is aimed at the image quality. With its 14mp (2652x1768x3 layer) Foveon sensor, the same as in the SD14 SLR camera, along with the latest TRUE (Three-layer Responsive Ultimate Engine) processor algorithms the camera can produce some stunning results for a compact. The sensor is some seven to twelve times larger than regular compact cameras. The dedicated lens, designed especially for the camera is sharp from the widest aperture of f/4 right through to the smallest aperture of f/16, a good range for a compact.

Shutter speed surprisingly has a variable maximum dependent on aperture used, varying between 1/1000^th when the lens is wide open to 1/2000^th when stopped right down. This is due to the shutter being fitted in the lens rather than the focal plane shutters used in SLR type cameras. It is an interesting diversion.

With a prime lens dedicated to the camera and no possibility of dust reaching the sensor, image quality is easily a match for most APS DSLR cameras on the market today and what the DP1 lacks in gizmos it more than makes up for in the output department!

The supplied software is good and has a well laid out GUI although some might deem it a little slow compared to programs dedicated to converting Bayer patterns.

It does, however, contain a number of useful features and the output is first rate.

Output in JPEG tends to warm the colours slightly.

Primary colours are boosted, the tones are even and the skin tone looks balanced.
Colours are rendered well, especially the Greens, although in JPEG colours are warmed slightly throughout the spectrum.	Fine detail, as in the masts in this image, are recorded with ease on the DP1.

The lens is sharp, even when wide open, and shows virtually no distortion.

Sigma DP1: Imatest colour

Sigma DP1: Imatest grey

Sigma DP1: Imatest noise

Sigma DP1: Noise Test
The DP1 supports ISO100-800 in full stop increments, and the Foveon sensor has come a long way since the first incarnation in the SD9. Noise is handled far better now than it was then. It is not until you reach ISO800 that any real evidence starts to show, and even there it is manageable in comparison to the earlier examples of the X3F sensor technology and the area where the system was most slated.

The ISO100 test.	The ISO200 test.
The ISO400 test.	The ISO800 test.

Sigma DP1: Verdict
The Sigma DP1 is certainly a specialist item designed for those to whom image quality is their key requirement. It's aimed at the professional and advanced amateur image-makers who want the quality it can provide in a pocket-sized bundle. The camera is simple and robust with no pretensions to being pretty, but it is practical with a sensible interface that's not full of fairy-ware!

Sigma DP1: Plus points
Simple, practical design and operation.
Outstanding image quality for a compact camera.
Robust build quality.
Useful optional extras.

Sigma DP1: Minus Points
Single focal length.
The lens cap.
Price.

FEATURES

HANDLING

PERFORMANCE

OVERALL

The Sigma DP1 costs from £550 and is available from the ePHOTOzine shop here.