Sigma SD1 review

The new Sigma SD1 may look like your average DSLR but beneath it basic exterior it packs a big megapixel punch

Its early announcement back at Photokina in 2010 meant Sigma’s new flagship model, the SD1, generated quite a buzz in the camera world from the beginning. However, its actual release back in June 2011 was considerably more subdued than we had anticipated. Keen to see if it lived up to the initial hype and find out whether it’s worth the heavy financial investment, we put the SD1 to the test.

Essentially this camera is all about image quality and size. Offering up a staggering 46 effective megapixels, this wouldn’t come so much as a surprise if the SD1 were a medium format, however, for a DSLR it’s unheard of. So how does a seemingly regular DSLR provide so many megapixels? The answer lies in the featured Foveon sensor and here’s how it works.

Each pixel in a regular DSLR sensor is responsive to a select primary colour of red, blue or green (RGB) in one layer. Generally these pixels, which are laid out in rows, will alternate between blue and green in one row and then red and green in another, this pattern will then repeat through the rest of the sensor. Green is the most dominant colour and appears on every row due to the fact that the human is more responsive to green light than it is to red or blue.

What the SD1’s sensor does differently is make each pixel responsive to all three RGB colours. This works through using three layers of light sensitive photodiodes, meaning that a direct image sensor, which has 155,000,000 pixel locations, can receive and capture full RGB colour information in every pixel.  This layering system enables the image resolution to be multiplied by three, as each pixel potentially encompasses three pixels when comparing a regular DSLR sensor to the SD1’s.

This concept, on the surface, is a little confusing and has left many photographers’ arguing over the accuracy of the technology, but really the image results speak for themselves. We put the camera to the test out on location and in the studio. Shooting in both RAW and JPEG file formats, we were keen to see how the SD1’s image quality and performance faired.

Under controlled studio light conditions the camera surpassed our expectations and is clearly built for this kind of shooting environment. With a built-in flash sync terminal, it’s ideal for pro studio users and features all the necessary shooting controls on the body. On review of our studio captures, images appeared well exposed and the camera’s auto white balance setting, which we also tested, did well to neutralise any colour casts from the flash light.  Given that the camera can produce large image sizes of a professional quality, the SD1 proved ideal for shooting commercial projects where images may be required for billboard size.

Although great in the studio, the camera wasn’t as versatile as we had hoped out on location. The SD1 struggled when working in direct sunlight and could be quick to blow out highlights, particularly in the sky when exposing correctly for the foreground. We were also a little disappointed by the camera’s ISO performance when shooting under low lighting conditions. Fairing well up to around 800 ISO, noise became present and image quality began to noticeably decline in settings upwards of 1600 ISO. However, when the SD1 wasn’t contending with low light or bright sunlit conditions, it did well to manage colours. Tones appeared realistic as apposed to being overly saturated or soft and we were pleased to see that when zooming in, detail was exceptional and sharp even for JPEG files.

Easy to use, the camera is built with a professional user in mind, and features all of the essential adjustment settings on the body. With two dials on the top plate, you adjust your drive mode and exposure settings quickly, and the additional quick set (QS) button on the back of the camera enables you to preview all of the camera and exposure settings before you shoot. There is even a depth of field preview button on the front of the camera that is fantastic for assessing the DOF effect via the optical viewfinder.

Unfortunately there is no live view mode available which is most likely down to the fact the SD1 doesn’t feature a built-in movie mode. This can of course be forgiven, as although video capture is a feature many photographers have come to expect from a high-end DSLR, the SD1’s technology has been focused towards the fantastic still imaging sensor. You can however still shoot in continuous burst mode, capturing up to 5fps in RAW format. Provided you are using the correct memory card, writing speeds are relatively quick in camera, which is thanks to the featured two TRUE II image processors.

Surprisingly lightweight, the camera’s magnesium alloy body made it easy to work with particularly during long studio shoots. The pronounced grip and deep finger groove on the front also means it fits comfortably in hand. Being weather sealed, the SD1 can also brave the elements on location and has a noticeable feel of durability and strength.

However one of the SD1’s biggest letdowns was the back LCD. The featured three inch screen doesn’t do captures justice when previewed in playback. Although 460,000dot, colours appear muted and almost entirely unsaturated on the screen, with noise appearing much sooner in ISO shots than it does realistically. Although a fairly good resolution screen for any other DSLR model, featuring in the SD1 it struggles and doesn’t match the quality of the images, sensor or camera build.  That being said, we anticipate the SD1 is most likely to be used in a studio setting, meaning you can slightly overlook the LCD quality by opting instead to shoot tethered, which will enable you to preview your captures more clearly out of the camera.

Overall we enjoyed testing the SD1 and were impressed by the camera’s incredible image quality and performance. With a recommended retail price of around £6200, it is an extravagant spend and we would have liked to have seen fewer flaws with improvements made to the LCD and ISO performance in particular. Still relatively new to the market, it will be interesting to see how the SD1 fairs amongst other pro camera choices and we are looking forward to seeing what Sigma do next with their incredible sensor technology.