Well here's another thing to think about..... what is the dpi of the image out of camera??? If you are upsizing from say 72 dpi or 96 dpi image out of camera to 300 dpi, the software is using interpolation to create pixels that don't exist..... You will see a degradation of image quality, even if you don't save as a jpeg. You seem to be doing everything else right, and that is the only thing I can think of that may be the cause.

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