JPEG and ePIC images are stored in a compressed format. Compression is lossy which means when you save a JPEG or ePIC file, there will be data loss. Data loss is the result of JPEG and ePICs ability to achieve high compression ratios. Higher quality settings result in less compression, while lower quality settings result in higher compression. Quality versus compression is a tradeoff.

The image compression ratio can be adjusted by setting the SaveJPEGLumFactor and SaveJPEGChromFactor properties. The SaveJPEGLumFactor adjusts the luminance or gray scale quality and the SaveJPEGChromFactor adjusts the chrominance or color quality. Lower settings for these properties result in higher quality images with less compression. Higher settings for these properties result in lower quality images with more compression.

For general use photographic type images, the settings of 32 for luminance and 36 for chrominance provides about a 12:1 image compression ratio with minimal data loss. Compression ratios and perceived image quality will vary depending on the image.

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