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Affinity Photo Desktop Windows, latest (non-beta) rev: 220.127.116.11 Win 10 x64 up-to-date, 16 GB ram, >45 GB on SSD, >400 GB on HD & defragged no SMART errors). GTX 1060 6GB. Camera: Sigma SD1M (M for Merrill, inventor of the Foveon sensor), X3F RAW files. Neither of these issues happen with my SD14. Reproducible. Two unexpected behaviours both occurring during RAW import, even with the same image file. Behaviour One Import B&W RAW image, and B&W setting is lost (appears with separate colour channels). Camera has two methods for obtaining high quality B&W images: 1) At time of capture, choose B&W setting on camera body, which flags RAW metadata to treat R, G, B results as one value (grey) per photosite. Actual raw data would still have RGB per photosite, but image should only open as greyscale. 2) In Post-Processing, extract only the Blue channel from raw RGB data, from every photosite. This method loses the photons from the R&G layers, but since the Blue layer is the top layer, it has the least noise, so is pretty good. The other side-effect to this method is that because only the Blue layer is captured, it would be like using a deep blue filter over the lens, making yellows black, reds very dark, etc. So some things may look a bit different from a full-spectrum B&W image. The advantage is that it is reversible (you can decide you preferred the image as a colour image afterwards, whereas the first method keeps everything B&W for good). I cannot find a way to achieve either method of getting a high quality B&W. I would prefer #1 (above) if I had to pick, as you get panchromatic response and lots of photons per photosite, resulting in ultra-low noise, just like from a Leica Monokrom. In this version, attempting this results in a lot of noise, even in a perfectly exposed image. In other RAW processors, I can use zero sharpening, zero de-noising (colour or luminance), and the images are clean. Also, default behaviour is to open as B&W, with only greyscale available (even Irfanview reads and presents the raw that way). I should note that it's not terrible noise, but the camera is capable of using these modes to deliver super creamy B&Ws, and I was hoping to be able to do that. Behaviour Two Import a RAW image taken at MED resolution, and the imported RAW will be auto-scaled up to FULL/HIGH resolution (I could not find how to defeat this default behaviour). Since it's not a perfect upscaling (I calculated around 47%), there are significant uprezzing artefacts, and it's not as sharp. The camera allows photos to be captured at LOW, MED or FULL/HIGH resolution. Again, it's not horrible, but it's nowhere near how other RAW processors handle it. The camera uses one of the native features (though not all manufacturers make use of the 'feature') of CMOS sensors, 'binning', where arrays can report as if they were a lower resolution sensor: for example, a 4x4 grid of photosites would electronically be merged to act like a single photosite, so that all the photons get added together, giving you lower resolution but super low noise images and more accurate colour. Plus, Foveon images are often upscaled 200% after the fact, and still yield as good images as a Bayer CFA, so the resolution impact isn't near as negative as one might think. Foveons are the best at detecting subtle colours and recording micro-contrast without destructive processing, but sadly, they only do that when shot at low ISO or under loads of exposure, so these are frequent methods users employ. Example: MED resolution photo (see green photo resolution) opened & upsampled/upscaled in Affinity Photo as a FULL resolution image (see yellow Affinity resolution). Also, this same photo was taken as a BW-only image, yet it is apparent that it contains hues. One positive upside I discovered from the comparative testing is that the GPU acceleration in Affinity Photo is faster than the GPU-aided processing in both Corel and much moreso than even Sigma's own software. Haven't benchmarked Rawtherapee or On1 on that yet. I have previously uploaded MED and FULL/HIGH resolution images, as well as colour and B&W images, from my camera to the Forum calling for sample images. Note that neither of these behaviours occur with my SD14 X3F (Foveon) images, so it is confined to the SD1M (aka Merrill). That exact same sensor is used in a few Sigma DP cameras as well (I believe it is the DP3 series), so they may exhibit identical behaviour for both these anomalies. Thanks very much. Still learning a lot about the software, but it has made some things that were unbelievably tedious and error prone into downright easy when using Affinity Photo. Perhaps I have overlooked something and that is also the case here.
I have a Sigma DP2 Quattro and while that camera is partially supported, I get better results from converting X3F files to DNG with X3F Tools and then develop the DNG in Affinity Photo (adjust white balance tint and it looks pretty good). The problem is that Photo doesn't honor the crop instructions. It does honor the size of the output file (5424 x 3616), but displays thick black borders along two sides and cuts off the opposite sides. Older versions of Iridient Developer used to do the same but their newest version works correctly. Here's a link to the tool in question: https://github.com/Kalpanika/x3f/releases/tag/0.54 Here's the announcement on Dpreview, you can find links to some DP Quattro RAW files (too big to upload) in that thread as well: http://www.dpreview.com/forums/thread/3890093 I have some ideas on how you can improve your own Sigma Quattro rendering, but the best would likely be to contact the authors of X3F Tools about integrating their import code in your own software. Their noise reduction is rather impressive...