DSLR Reviews

Sigma SD1 DSLR Review

George Schaub  |  Sep 30, 2011

The new Sigma SD1 uses a new Foveon sensor with a nominal resolution of 14,8 MP which is referred to by Sigma as nearly a 46 MP resolution (nominal resolution x 3 color channels RGB). The new camera has a lot of professional features.

The SD1 is Sigma’s new flagship SLR system. It uses a brand new sensor with Foveon technology and a nominal resolution of 14.8 MP. This means that the camera is able to record RGB information for every single pixel. Standard digital cameras use sensors with the “classic” Bayer pattern, which means that every single pixel detects only one color information (red, green or blue) and then must undergo color interpolation.

The camera uses the Sigma lens mount system. We used the standard zoom lens SIGMA 18-50mm F2,8-4,5 DC OS HSM and the Sigma MAKRO 70mm F2,8 EX DG for our tests.

The camera has a massive body. The right hand side grip is a bit small, however, compared to similar sized cameras among competitors. Nevertheless, the overall size is complemented by the camera’s large mode dials on the top. The left dial is used as power switch and for selecting shooting modes like single shot, continuous shooting or self-timer mode. The dial on the right hand side offers the standard exposure modes P, S, A and M. In addition, the camera offers three custom settings that are defined by setting up the camera with the desired parameters and saving them as C1 to C3 settings in the LCD menu.

The Sigma offers two mode dials on the top. The photographer uses the left dial to choose the image mode (single shot, burst mode, selftimer) and the right dial to choose the exposure program. Two setup dials (near the shutter release button and near the back)  allow for changing all parameters very quickly and efficiently.

The 3-inch LCD has a standard resolution of 460.000 RGB dots, which isn’t acceptable for a camera in this price range. The SD1 can’t be used in live preview mode; the LCD is used solely for the menu and for image review.

The camera has a 3 inch sized LCD with 460.000 RGB dots. For very fast setup it uses the “QS” button (two quick menus with most important parameters), a standard cursor field and a lot of dedicated function buttons.

There are numerous dedicated function elements that help to setup the camera very quickly and easily. By pressing the “QS” mode the camera will show the first direct menu for setting up ISO speed or exposure mode (spot, matrix, center weighted). Pressing the QS button allows setup of resolution, image mode (JPEG, raw, raw + JPEG) and more. Other parameters are changed by pressing the four buttons on the standard cursor field.

The photographer can use two setup dials to change images parameters while shooting. The front dial near the shutter release button changes the aperture, the dial on back side of the top (which can be reached with the right thumb) allows for changing of shutter speed. Both dials are also activated when changing menu parameters.

All interfaces are located on the left hand side of the body and covered by a rubber cap. The camera offers USB interface, TV interface, X-sync flash interface, a port for an optional remote control and a DC interface.

The camera requires what we consider a lot of time to save images in raw mode. During our tests we used fast SanDisk Extreme CompactFlash cards. With this card the camera needs 10 to 12 seconds to save a single raw file. The buffers size allows the photographer to take up to 7 images (same in burst mode with 5.5 images per second) and after that the camera will start to save the images on the CF card.

Comments on Image Quality:
The camera showed very natural looking images, although with an overcautious saturation. The test chart was reproduced with only 81.16 percent, but the resulting chart (see below) proves that the color errors are mainly based on this saturation. The colors shows a direction into the center area of the chart which means that they are desaturated, but show basically the right color nuance. The automatic white balance system tends towards very cool nuances, which is also visible in the portrait test shot. Only red colors are a little over emphasized. When taking images in raw mode the camera shows very precise color reproduction.

The camera displayed a remarkably performance in our resolution tests. The test chart was reproduced with 2936 lines per picture height, which is an excellent result for a camera with a nominal resolution of 3.136 lines per picture height. Maybe even more important is the extremely high quality of the data. There are absolutely no image moirés noticeable and all details look very clear and crisp.

The reproduction of details is excellent. Hair, eyelashes or the fabric of the model’s t-shirt is crisp and clear and shown without any color moirés or fractions in extreme details. The white balance system tends towards very cool reproduction. This effect is accentuated in this image shot with a fluorescent light system.

Take a look at the metal sieve in the upper left of the standard test box shot, which is reproduced in every single detail. There are only minor chromatic aberrations visible. The camera yields very fine details, especially when shooting in raw mode. Using these images, interpolations up to 200 percent are possible and still show really good results. We did printing tests with those interpolated images and achieved a resolution of 9408 x 6277 pixels.

Even though the camera has a nominal image resolution of 14.8 MP, its images really deserve Sigma’s “46 MP” label.

Just like the portrait photo, the standard test box shot shows all details in a crisp and clear way. In this case the white balance system did a good job and the shot shows a neutral gray background. Best results are achieved by shooting raw.

While the sharpness and resolution results are on a very high level, the results in the noise and dynamic range tests are only on a good level in lower ISO speed settings and unacceptable in the highest ISO ranges. The camera showed good results in images taken with ISO100 to 800, but noise will increase in an extreme way in images taken with ISO 3200 and 6400. While the luminance noise factor is on an average level (between 0.51 and 1.82) it rises considerably at ISO 3200.

The camera is able to shoot at up to ISO 6400, but showed some strange effects in the highest ISO mode. When making tests we take noise and dynamic range shots in manual camera mode, which means we are shooting with a fixed aperture and changing shutter speed to compensate for the rising ISO speed. For example: The first shot is done with ISO 100 setting and 1/80 s and f/8. The next shot is done with ISO 200 and 1/160s, f/8, and so on.

Using this technique we got standard image results with the Sigma SD1.  However, when taking the shot at ISO 3200 the image was remarkably darker, even though the shutter setting was only half the speed compared to the previous shot with ISO 1600. When we did the shot with ISO 6400 the image got even darker and very noisy, even “grainy.” Color noise is clearly visible in images taken with ISO 1600 and higher, images taken with ISO 3200 couldn’t be reproduced in an acceptable way.

Pro:
+ Excellent crisp and clear, richly detailed images.
+ Very good handling system (two mode dials, two setup dials and many function buttons)

Con:
- Very long time required for processing and saving raw images (55 MB per image)
- Very high noise results in higher ISO speed settings (higher than ISO 1600)
- No live preview on LCD screen, no video capabilities

This review was created using data and opinions of Betternet, the testing lab we work with in our association with TIPA.

COMMENTS
Scott Kennelly's picture
Submitted by Scott Kennelly on October 7, 2011 - 4:16pm

You need to tell that to Leica and all the other companies that are producing cameras for $20,000 or more. Do you know what resolution the Canon D1s Mk III screen is? Here's the answer: 230,000 RGB dots

So is the Canon screen not good enough? I think that is a silly statement, considering the Nikon D3x is just about the only camera with a higher resolution screen. It is a "review" screen, afterall, and that many pixels is certainly very high resolution. At a resolution of almost 768x600, that 3 inch screen gives a much finer detail image than what you can get on a computer screen. Most high-quality computer screens give about 6 times the resolution, but about 30 to 40 times the area. That makes their pixel density MUCH worse than the screen on the SD1. With a diagonal measurement of more than 6 times the SD1 screen, a 19" computer screen actually has much more than 6 times as much area to fill, but with only about 6 times as many pixels.

The fact is, even the 230,000 dot screen on the Canon 1Ds Mk III, which was heralded as a high quality screen when it came on the market, gives a more detailed view in it's 3 inch area than a similar area in even the highest quality 19" computer screens, or even the new 27" Mac screen. I'm not saying that looking at the whole computer screen does not give you such a detailed view, but if you take a similar area, then you will have a much more detailed view on the SD1 screen than you can get on a high quality computer screen.

Now does that make sense? Do we really need more than twice the quality that is on the most expensive Canon camera made?

I don't think so, and Leica didn't either. That's why when they recently introduced their S2 camera, they did NOT opt to match the existing Nikon D3x. Instead, they used a screen similar to the one on the SD1. That camera sells for more than $20,000. So please, tell me how you can say such a silly thing. What? Leica doesn't know what they're doing? That's what you're saying by making a statement like, "The 3-inch LCD has a standard resolution of 460.000 RGB dots, which isn’t acceptable for a camera in this price range."

I think that this article was written with a negative slant from the beginning. Without pointing out the fact that the camera has a superior resolution to the top Canon model and a similar resolution to the much more expensive top Leica model, you do an injustice to the SD1, and you make it look as if you are being negative from the beginning of the article. Your list of Pro: and Con: are very short, and you fail to point out that the SD1 gives the absolute best image quality in its price range and the best high-ISO noise levels in the entire range of APS-C size sensor cameras. In fact, you list the SD1 noise levels as a "Con:" - it is actually the best performer, when you consider its sensor size and resolution.

I was surprised to read, "Even though the camera has a nominal image resolution of 14.8 MP, its images really deserve Sigma’s “46 MP” label." At least you did not totally can the SD1, even though you do seem to be somewhat negative about it.

You fail to point out many more things in this article, both positive and negative. A more extensive review would have been helpful. I would like to see more photos of the camera, including what it looks like through the viewfinder, what the weather seals look like, etc.

Success is in the details, and I think this article is a failure.

X