ggibson
Well-known member
I picked up a Sigma SD Quattro with 30mm f1.4 kit lens last month and tested it against my Sony A7rII and Sigma DP3M. I thought I would share some comparison images and impressions here for folks who might be curious to how image results from these cameras compare. Standard disclaimer--I'm not a pro reviewer here so you must take results with whatever grain of salt you would like. I don't have a perfectly comparable focal length to compare across each camera, so the framing is obviously not perfect between the different cameras (I'm using primes here). These shots are taken by moving the camera/tripod setup to keep the object approximately the same size in the frame. This gives a pretty good look at resolution of the sensor. I also ended up shooting these wide open so that I could see the different bokeh/compression results from each lens. Focus is on the green leaf in the center.
Processing: for the Sigma X3Fs and X3I, I process them in Sigma Photo Pro and export them as 16-bit TIFFs. Then, I import these into Lightroom with the Sony RAWs and the Sigma DNG. After attempting to color-match these results and find the best balance of noise reduction for each file, I exported the Jpegs here. This part is difficult to find a single process that works well for all files (Sigma DNGs and X3Fs behave a bit differently in my experience), so insert your grains of salt here as needed. They are the best results that I could come up with for each file type in a reasonable amount of work.
Here's the lineup all together:
Large jpg files for download:
Sony A7rII + Leica 40mm Summicron-C f2
Sigma SD Quattro + 30mm f1.4 DNG
Sigma SD Quattro + 30mm f1.4 X3F (Single Shot)
Sigma SD Quattro + 30mm f1.4 X3I (Multi Shot/Super Fine Detail)
Sony A7rII + FE Zeiss 55mm f1.8
Sigma DP3 Merrill 50mm f2.8 Macro
Bonus:
Sony A7rII + FE 28mm f2
Sony A7rII + FE 16-35mm f4 @ 35mm f4
My takeaways:
Sony vs. Sigma: Not too surprising that the A7rII wins in terms of detail and clean files. Not really surprising considering the A7rII costs 3x more. The Sigma Quattro files (DNG and X3F) and Merrill X3F were all relatively noisy even at ISO 100. Much less latitude to push/pull these files in post than the A7rII.
Sigma Quattro DNG vs. X3F: Detail-wise, they produce similar levels of output, but I think that Sigma's noise reduction in SPP is more finely tuned to the particular Quattro signal noise than the tools in Lightroom. Like DPR mentioned in their review, it was impossible for me to color-match between these files. The DNGs come out looking closer to the Sony A7rII files color-wise, although there are still differences. I liked the X3F files slightly more, but DNG is definitely more simple for me to process. At least you have both options, but for "the" shot, I'd go with X3F or X3I.
Super-Fine Detail Mode on the SDQ: I feel like SFD mode on the SDQ produced some of the most spectacular files I've ever used. Super clean signal/noise with noticeable improvements in detail. Maybe not quite as high-res as a single A7rII RAW, but close enough and with beautiful colors. I might actually prefer SFD's files if I could use it all the time. The biggest downside is obviously that it's a multi-shot mode and subject to movement artifacts between shots. This can be remedied with extra effort by extracting a single image and cloning if you're willing to put in the work. If you're shooting in a studio with controlled lighting, however, the SDQ delivers amazing results at a fraction of the cost of the A7rII. Another takeaway for me after using this mode is that I should try some multi-shot processing with the A7rII at some point. I know the Smooth Motion app does this in-camera, although it does not bracket to increase dynamic range like the SDQ.
Sigma DP3 Merrill: This little camera continues to impress me with its output. While it doesn't deliver the same level of resolution as the A7rII, the micro-contrast/edges on the Merrill file can stand out more distinctly. I definitely plan to keep it at least for panoramic stitching. In my experience with the camera (not just from this test) it really does have some distinctly different look to its files. Clouds and night shots especially can look completely different. The Merrill output can be very noisy, so maybe some shot stacking would be a good technique with these files as well. Overall, quite a bargain for its image-quality if you can shoot within its limitations (ISO 100, slow AF).
Conclusions? Well, I sold the SDQ but mostly because I didn't want to start investing into another lens system and also ultimately my goal is to move towards a smaller camera kit. I like Sigma cameras pretty well as a specialized compliment to a bayer system, but I rely too much on fast continuous AF, high ISO, and high dynamic range in most of my shooting to let me keep the SDQ. For certain photographers they can really be great cameras. I found the SDQ to be the most usable Sigma camera I've tried so far (I've had the DP1x, DP2Q, DP3M, and now SDQ). If Sigma can come up with a new smaller DP camera, I'd be really interested. Until then, I can get my foveon fix from the DP3M.
I hope this comparison is useful or interesting. Let me know what your experiences are or what you think of the examples I've shared.
Processing: for the Sigma X3Fs and X3I, I process them in Sigma Photo Pro and export them as 16-bit TIFFs. Then, I import these into Lightroom with the Sony RAWs and the Sigma DNG. After attempting to color-match these results and find the best balance of noise reduction for each file, I exported the Jpegs here. This part is difficult to find a single process that works well for all files (Sigma DNGs and X3Fs behave a bit differently in my experience), so insert your grains of salt here as needed. They are the best results that I could come up with for each file type in a reasonable amount of work.
Here's the lineup all together:
Large jpg files for download:
Sony A7rII + Leica 40mm Summicron-C f2
Sigma SD Quattro + 30mm f1.4 DNG
Sigma SD Quattro + 30mm f1.4 X3F (Single Shot)
Sigma SD Quattro + 30mm f1.4 X3I (Multi Shot/Super Fine Detail)
Sony A7rII + FE Zeiss 55mm f1.8
Sigma DP3 Merrill 50mm f2.8 Macro
Bonus:
Sony A7rII + FE 28mm f2
Sony A7rII + FE 16-35mm f4 @ 35mm f4
My takeaways:
Sony vs. Sigma: Not too surprising that the A7rII wins in terms of detail and clean files. Not really surprising considering the A7rII costs 3x more. The Sigma Quattro files (DNG and X3F) and Merrill X3F were all relatively noisy even at ISO 100. Much less latitude to push/pull these files in post than the A7rII.
Sigma Quattro DNG vs. X3F: Detail-wise, they produce similar levels of output, but I think that Sigma's noise reduction in SPP is more finely tuned to the particular Quattro signal noise than the tools in Lightroom. Like DPR mentioned in their review, it was impossible for me to color-match between these files. The DNGs come out looking closer to the Sony A7rII files color-wise, although there are still differences. I liked the X3F files slightly more, but DNG is definitely more simple for me to process. At least you have both options, but for "the" shot, I'd go with X3F or X3I.
Super-Fine Detail Mode on the SDQ: I feel like SFD mode on the SDQ produced some of the most spectacular files I've ever used. Super clean signal/noise with noticeable improvements in detail. Maybe not quite as high-res as a single A7rII RAW, but close enough and with beautiful colors. I might actually prefer SFD's files if I could use it all the time. The biggest downside is obviously that it's a multi-shot mode and subject to movement artifacts between shots. This can be remedied with extra effort by extracting a single image and cloning if you're willing to put in the work. If you're shooting in a studio with controlled lighting, however, the SDQ delivers amazing results at a fraction of the cost of the A7rII. Another takeaway for me after using this mode is that I should try some multi-shot processing with the A7rII at some point. I know the Smooth Motion app does this in-camera, although it does not bracket to increase dynamic range like the SDQ.
Sigma DP3 Merrill: This little camera continues to impress me with its output. While it doesn't deliver the same level of resolution as the A7rII, the micro-contrast/edges on the Merrill file can stand out more distinctly. I definitely plan to keep it at least for panoramic stitching. In my experience with the camera (not just from this test) it really does have some distinctly different look to its files. Clouds and night shots especially can look completely different. The Merrill output can be very noisy, so maybe some shot stacking would be a good technique with these files as well. Overall, quite a bargain for its image-quality if you can shoot within its limitations (ISO 100, slow AF).
Conclusions? Well, I sold the SDQ but mostly because I didn't want to start investing into another lens system and also ultimately my goal is to move towards a smaller camera kit. I like Sigma cameras pretty well as a specialized compliment to a bayer system, but I rely too much on fast continuous AF, high ISO, and high dynamic range in most of my shooting to let me keep the SDQ. For certain photographers they can really be great cameras. I found the SDQ to be the most usable Sigma camera I've tried so far (I've had the DP1x, DP2Q, DP3M, and now SDQ). If Sigma can come up with a new smaller DP camera, I'd be really interested. Until then, I can get my foveon fix from the DP3M.
I hope this comparison is useful or interesting. Let me know what your experiences are or what you think of the examples I've shared.