Originally posted by HoustonBob Image #4 is not sharper
...it is on my monitor...
Originally posted by HoustonBob The grain in film pictures was why nobody sharpened pictures until digital came along.
Interesting notion...I have darkroom experience going back 4 1/2 decades and don't remember having the option of sharpening for optical enlargements. That being said, it is possible and common enough to apply USM to scans from film negatives/prints. Most scanners have native support for such and sharpening may be applied in post the same as with any other digital image. I tend to not do with high resolution scans due to artifact potential.
As for the role of grain in edge perception and acuitance, that is an interesting and complex topic. I am not sure it is directly applicable to noise in a direct digital capture. With film, grain is a byproduct of image formation and it presence is proportional to the amount of converted silver (i.e. part of the image) and has the potential to reinforce edge perception as a result. With a digital capture, noise replaces the image pixel-per-pixel and is not an intrinsic part of the image.
Steve
Last edited by stevebrot; 05-05-2016 at 04:10 PM.