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This is probably covered somewhere on the forum, but I couldn't find it. A recent forum discussion piqued my curiosity about AP's JPG compression algorithm regarding quality loss, file sizes, etc. So, I took an original image (from an old Canon 40D, 2538 x 3866 pixels) and exported to 8-bit RGB TIFF and 15 separate JPGs of varying quality levels (quality 0 to 100). I have generally used Quality 85% up to now, since it usually retains very acceptable quality with a significant reduction in file size. All the exported files are in the attached ZIP file. I picked an image with some fine details and some smoother areas, as JPG compression works differently in high and low frequency portions of the image. I found that anything below a quality of about 20–30% generally resulted in severe posterization and artifacts. JPG quality of 100% results in huge file sizes and is probably not required, except perhaps for special cases. Even lowering the JPG quality from 100% to 95% or 98% results in a significantly smaller file size. Interestingly, large portions of similar, low frequency color (e.g., skies, gradient backgrounds, smooth walls, etc) probably require higher quality levels to avoid visible posterization and artifacts. Higher frequency images can often get away with more compression (i.e., lower quality and smaller file sizes) without it being as noticeable. Below are the file sizes for the various JPG compression qualities (all files were 2538 x 3866 pixels in size). Different files will compress differently depending on saturation, brightness range, amount of detail, etc. JPG 0% 82KB JPG 5% 104KB JPG 10% 157KB JPG 20% 262KB (ones in red were generally pretty bad and resulted in extremely noticeable artifacts) JPG 30% 379KB JPG 40% 497KB JPG 50% 622KB (Not too bad, at least in this test image, but a little soft) JPG 60% 891KB JPG 70% 1.1MB JPG 80% 1.5MB (Acceptable quality in this test image) JPG 85% 1.9MB (A good compromise for my general needs, unless maximum file size reduction is critical) JPG 90% 2.5MB JPG 95% 3.8MB JPG 98% 5.9MB JPG 100% 9.8MB TIFF 8-BIT 15.5MB (no compression) If smaller file sizes are critical, I'd be inclined to reduce JPG Quality level to 50% or even lower, depending on the image, especially on images that are mostly higher frequency. Where gradients and smooth, similarly colored areas are prominent, you may wish 50% or higher. On size doesn't fit all, so some experimentation is usually in order. JPG Quality-Filesize Comparisons.zip

Hello, I just faced a situation which makes me worry, and I'd like to understand whether I do something wrong or it is a real issue. I just bought a Nikon Z8, and I dowloaded all the Nikon softwares (NX tether, NX studio) for tethering. For developing and editing I wanted to keep using Affinity Photo, but when I sent to raw file from NX Studio to Affinity photo I realised that they are different. Please have a look at the attached pictures: 1. back of the camera, 2. in NX STUDIO 3. Affinity Photo develop persona. The histogram in the camera and NX studio is the same, but different in Photo and the overall, sharpness, and image quality as well. If I choose don't apply cone curve, the histogram is just even more different, and goes tot he darker side. If I change RAW Engine to Apple it's quite the same. My question is, whether this is something that can be fixed by some settings, or Affinity just can't process the NEF files equally well? Thank you very much in advance for your kind answer. I would love to be able to continue working in Photo. Zoltán

Every eps file I import into Affinity Designer 2 looks awful. The graphics are separated into unusual sections and gradients and shadows are changed (misplaced or redrawn) and some graphic elements look as though they have been rasterized (The graphic no longer appears smooth and well drawn.... they look pixelated). Every single eps I've tried to import turns out this way. Is there a setting that needs to be adjusted? Not sure how useful Designer will be if it can't handle eps files. Please help. I've attached and eps and a jpg of the same file to you can see the two and how Designer is treating the eps. Daniel Christmas background blue v kr.eps

Hi Guys, I am looking for some direction here as I have read through many of the forum articles on this topic but it just doesn't seem to work for me. I am uploading my cover photo image to facebook and no matter how I export from designer it still looks like crap and pixelated when uploaded. I have set me size to 851px by 315px made sure I am below 100kb selected SRGB and no matter what it still looks like crap. What am I doing wrong? am I exporting it incorrectly? I have tried it in both JPEG and PNG and the result looks the exact same. Any advice would be greatly appreciated.

Hello, I would like advice on how to downsize a photo without losing the sharpness and quality. I have images that are too large for my website - eg 4896x3264 px. I want to have them 900px on the horizontal dimension but when I use 'Resize Document' the quality is drastically reduced with lots of pixillation. I can use Unsharp Mask to improve it a little, but it is nothing like the larger image in quality. Is there a way to downsize without this high level of quality loss? I have attached the two versions of my image for refrence

So this is a brand new issue I just started having. I am doing pixel work and whenever I move or flip the image, or even merge two layers, the pixels suddenly become a blurred mess. I am not even resizing them. They just blur randomly whenever I try basic editing. This pixel work is very important for the game I am working on but this blurring problem is stopping my entire production ORIGINAL: Flipped: Merged The same blurriness also occurs whenever I move these around the canvas if there is objects on the background. Please help.