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What are the advantages/disadvantages of each image file format?
JPEG - This filetype has the lowest filesizes but compression artifacts may be visible as you lower the quality option, since JPEG is a lossy format, the quality loss is especially easy to see on sharp borders, on smooth borders and shading, like photos or realistic looking drawings, the quality loss is barely notable, if you choose a high JPEG quality. After you saved an image as JPEG, you should not open, change and save it as JPEG again, since it makes the image's quality drop dramatically.
PNG - This filetype is lossless and compressed, however it can take longer than JPEG to save files, and they come out a little larger than JPEGs, however, there is no quality loss at all, even if you re-open and re-save it as PNG.
BMP - This filetype is lossless, large and uncompressed, and is unsuitable for the web. We encourage you not to use this image type to upload your deviations, since many browsers will not even display the file while browsing.
When saving your file in the JPEG format, you have a quality scale option of 1 through 12, with 12 being the highest quality. If you are using the "save for web" choice, the quality scale option will show as 1 through 100%, with 100% being the highest quality. We highly recommend that you submit files in JPEG format, saving as a straight JPEG file at the highest quality level, as it offers the best combination of quality and small file size, making it easier for you to upload quality source files.
We do not recommend using the progressive saving method for JPEG print files, as it can cause processing errors for the printers.