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pdurrant · 07-10-2016, 04:55 AM

The image you posted is not 8-bit (indexed colour) but 24-bit. That is, 8 bits each for Red, Green and Blue. You won't get any benefit from going to 16-bits per colour.

The problem is as Jellby said - moire patterns from the poor resizing algortihm. Looking at the image you posted, that doesn't look like a scan of an actual print from an engraving, but a halftone image of an engraving.

The way I'd handle it would be to apply some guassian blur to rmeove the halftoning, and then apply just a little unsharp mask, barely enough to be noticeable at 200%.

And doing that gets the image I attach, which should look pretty good, even in ADE.

[now uploaded as a jpg full size]

07-10-2016, 04:55 AM	#8
pdurrant The Grand Mouse 高貴的老鼠 Posts: 74,002 Karma: 315160596 Join Date: Jul 2007 Location: Norfolk, England Device: Kindle Oasis	The image you posted is not 8-bit (indexed colour) but 24-bit. That is, 8 bits each for Red, Green and Blue. You won't get any benefit from going to 16-bits per colour. The problem is as Jellby said - moire patterns from the poor resizing algortihm. Looking at the image you posted, that doesn't look like a scan of an actual print from an engraving, but a halftone image of an engraving. The way I'd handle it would be to apply some guassian blur to rmeove the halftoning, and then apply just a little unsharp mask, barely enough to be noticeable at 200%. And doing that gets the image I attach, which should look pretty good, even in ADE. [now uploaded as a jpg full size] Attached Thumbnails Last edited by pdurrant; 07-10-2016 at 06:49 AM.