Originally posted by biz-engineer Can I apply a ratio to radius/amount , based on the ratio of display resolution/print resolution, so that to achieve the same look on display and in print?
I think that's the key: sharpening algorithms work on pixel counts (radius etc), but we view images in terms of spatial resolution (dpi, lines per inch, whatever). That's why one can/should sharpen on the resolution for printing, viewed at the dpi the screen/print will look like. Otherwise if I take a 36mp (or whatever) image, sharpen it, then downsize it to 2mp so it has 300dpi for a 4x6 print, whatever effects were on the 36mp are lost due to down sampling. As pixel density, the 36mp image would be technically able to produce 1200 dpi for 4x6 print size, though I think we'd need a microscope at that point to see any more detail.
btw this was a great thread to read so far on sharpness vs actuance, something to think about when processing even if I'm not printing