On the other hand and not to disagree with anyone wrt sharpening but I have found the only accurate preview for an export is what you see at 100%… the DT preview as you zoom out scales and at least for me hides noise and detail pretty quickly…so you can call it pixel peeping but you do have to experiment a bit to get to know DT. There was an old thread … ( Denoising high-ISO images: a sourdough bread - #54 by Underexposed ) The OP wanted to know why his image had so much noise still after denoising when he saw none on the screen. It was a black and white version and really you only saw it at 100% and what you saw there matched the export… there can be other artifacts as the one I noted just the other day playing with a playraw image… Windows build of R&Darktable.... - #56 by priort So what I am saying is there is also the factor of what are your preview conditions and are they a reliable representation of the final output and as @MarcoNex mentions the intended media and viewing conditions for output will play an important role as well… The above example is related to noise but would likely apply to sharpening as well…