I got LR 5 on disc when I purchased a Canon Mark iii, I have since bought a Canon 750D and when I try to import my RAW files to Lightroom they are not recognised. Why is this?
Lightroom 5 does not support Canon 750D raw files.
You can either upgrade to Lightroom 6/CC or use free DNG Converter to convert raw files into DNG and access those DNG files in Lightroom 5.
Reference link: Cameras supported by Adobe Camera Raw
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