Camera Review: Sigma SD Quattro

March 30, 2017

By Greg Scoblete

Sigma SD Quattro

Did you know that Sigma makes cameras because of zombies? In a recent interview with LensVid, CEO Kazuto Yamaki explained that Sigma persists in the camera market because, among other reasons, his late father, the company’s founder, wanted to become a camera maker and if Sigma stopped producing cameras, “he would come back to me as a zombie and he may try to kill me.”

So when we handed the sd Quattro over to N.J. photographer and director David Patiño we were acutely aware that this camera may be all that stands between civilization and the zombie apocalypse.


The sd Quattro is Sigma’s first mirrorless camera and it accepts the company’s own Sigma-mount lenses (Sport, Contemporary and Art). Like the company’s existing line of Quattro advanced compact cameras, this model uses an APS-C-sized Foveon X3 sensor. Where traditional Bayer sensor designs split up pixels along a single surface to capture color data, the APS-C-sized X3 uses a three-layered, vertical design. One layer captures red chrominance information, the other captures green chrominance data and the top layer captures blue chrominance plus luminance information. The X3 sensor has no optical low-pass filter, either, so it’s soaking up as much resolution as possible.

Because of its unique design, the sd Quattro’s megapixel math gets a little convoluted. Sigma claims that the three individual sensors collectively have an effective resolution of 29-megapixels—the blue sensor accounts for 19.5-megapixels, the other two for 4.5-megapixels—but also says these 29-megapixels have the resolving power of a traditional 39-megapixel Bayer sensor found on most other cameras.

Beyond its novel resolution, the sensor offers a native ISO range of 100-6400. You’ll have a 9-point autofocus system with face detect capabilities and low light metering down to -1EV. Shutter speeds range from 30 sec. – 1/4000 sec. and there’s a bulb mode for exposures up to 2 minutes long.

Unlike most mirrorless cameras in its price range, the sd Quattro has a fairly Spartan feature set. There’s no Wi-Fi, no GPS and no video recording.


Sigma cameras are known for their off-centered industrial design and the sd Quattro is no exception. The camera’s body mushrooms out from the handgrip so that it looks like you’re holding a ping-pong paddle, not a camera. That said, Patiño says he was surprised at how well it handled. The grip is quite comfortable, but the sd Quattro is physically larger than every crop-sensor mirrorless we’ve used. What’s more, the lens mount protrudes more than an inch from the body, making every lens you mount to it stick out that much further. Compact, it is not.

There are only two dials (for aperture and shutter speed) on the sd Quattro so most of your navigation is button-based. There isn’t an abundance of external buttons and outside of assigning the direction of the dials’ turn, you can’t customize the camera.

The magnesium alloy body is nicely weather-resistant. You’ll frame your scene through a 3-inch LCD display or a 2.36 million dot EVF.

Image Quality

The sd Quattro is capable of capturing some very beautiful, film-like images, Patiño tells us. But you need to know the camera’s strengths and weaknesses to coax the best images from it, he adds. “This isn’t an everyday camera,” he says. Instead, it’s ideal for shooting landscapes and portraits with abundant light and plenty of colors.

The camera is not built to shoot at high ISOs or to catch even moderately fast moving action. Set the camera to any ISO value above 200 and your RAW files will be shot through with so much noise, they’ll be very difficult to patch up. Given how far other mirrorless cameras have come in the ISO department, the X3 sensor’s inability to function well is a serious drawback for anyone shooting in low light.

To coax the highest quality image from the sd Quattro, you need to process the RAW files using Sigma’s Photo Pro software.** Patiño tells us his experience with the software was often slow and buggy compared to other RAW image processors. It does provide a fairly comprehensive set of processing tools, plus some useful color profile presets to tweak images.


The sd Quattro isn’t built for speed. It takes roughly 7-10 seconds for RAW+JPEG files to write to the card, though the buffer memory is large enough that you can keep shooting while the files write. What you can’t do is shoot and instantly review your capture (sorry chimpers). In an era when cameras like Sony’s a6500 boast of hundreds of AF points, the sd Quattro has but nine—and even shooting single point isn’t super responsive. Patiño likens it a bit to a medium-format camera in that it requires a bit more time and composition to get the shot you want than your typical mirrorless.

While the sd Quattro has a sharp LCD and EVF when it comes to displaying menu items or camera settings, the feed from the camera’s sensor doesn’t appear as crisp and it’s not terribly responsive. A quick twist of the camera can sometimes make the live view warble.

Bottom Line

The mirrorless camera market is intensely competitive and if you run the sd Quattro up against all of its comparably-priced competitors, it’s going to come up short in a number of areas. It lacks Wi-Fi, 4K video recording, GPS, an electronic shutter, tilting or touch display. Speed-wise, it’s considerably slower than almost any camera in its price range. Low light capability is also lacking. What you do get is a camera that does produce truly film-like images that can access Sigma’s extensive lineup of lenses.

“When the image hits, it’s stunning,” Patiño says. But getting those hits isn’t easy.

** Since our review, Sigma has released new firmware for the sd Quattro (available here). The new firmware enables the following features:

  • Saving images in DNG format (RAW 12-bit)
  • Compatibility with the Live View Display of Sigma Capture Pro
  • Compatibility with the SFD mode of Sigma Capture Pro
  • Faster AF speed of Contemporary, Art and Sports lenses by about 10 – 30%; improved AF accuracy
  • Improved color rendering of the White Balance’s Flash mode when used with the Sigma Electronic Flash EF-630 (the latest firmware for the EF-630 is required)
  • Bug fixes – AF Shooting button did not work while the camera was using AF Lock; adjustments on the marked images could occasionally freeze the software when the card had an X3I file in it
  • Improved software performance to achieve better stability

Sigma sd Quattro

PROS: Can produce stunning images; comfortable ergonomics.
CONS: No 4K video recording; poor low light capability; lacks Wi-Fi and GPS; fewer features than comparably priced competitors; sluggish AF.
PRICE: $799


Want to see more mirrorless camera reviews? Check out PDN’s archive here.

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