Luminous Landscape Forum
Raw & Post Processing, Printing => Digital Image Processing => Topic started by: RMW on December 06, 2020, 04:26:10 pm
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Hi All.
I'm in High Sierra v. 10.13.6 using PS 21.2.4 release.
When resizing an image from 21.3x10.419 Tiff to half that size jpg - and reducing the res from 360 to 300 - the image gets badly over sharpened.
Used "Resample" and "Automatic" settings.
Don't know why.
Any help very much appreciated.
Richard
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You are viewing at 1:1 (100%)?
Too sharp for what, viewing on-screen only?
Sharpening for other output can appear on-screen as too sharp but print ideally. We need more info.
In the meantime: http://creativepro.com/out-of-gamut-thoughts-a-sharpening-workflow/
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Andrew.
Thank you for replying.
I have been viewing them at 100 %.
The original full size version has good resolution and sharpening.
Here is the reduced jpg. It looks terrible to me.
Richard
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I don't see over sharpening artifacts, but the processing is very contrasts and has few mid tones. Did you use some raw editor and shoot in raw? I think the processing itself needs to be examined, not the sharpening. There aren't halos.
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The automatic setting does something like a genuine fractals type of resampling. Try Bicubic (Smooth Gradients).
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The automatic setting does something like a genuine fractals type of resampling. Try Bicubic (Smooth Gradients).
The automatic setting in Resample picks differing sharpening algorithms just as if you select Automatic in General Preferences (Image Interpolation), so, one for sizing up, one for sizing down and based on the image type. If you leave the interpolation option set to Automatic, Photoshop will automatically select the Preserve Details algorithm when it detects that the user is enlarging the image. When downsampling (reducing) the size of an image, the Automatic option will choose Bicubic Sharper. Of course, you can override this to whatever you desire. Ditto with automatic setting and Free Transform.
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You are viewing at 1:1 (100%)?
Too sharp for what, viewing on-screen only?
Sharpening for other output can appear on-screen as too sharp but print ideally. We need more info.
In the meantime: http://creativepro.com/out-of-gamut-thoughts-a-sharpening-workflow/
Andrew,
Bruce's article that you quote suggests that when evaluating output sharpening on screen it is often advantageous to view the image at 50% or even 25%, while avoiding "odd" percentages. I think 4k screens were before Bruce's time, but one should remember that 100% on 4K appears smaller than with full HD or even lower resolution screens and take that into account. Sharpening halos are less likely to be seen at 100% on 4K than with lower resolution screens.
Cheers,
Bill
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I'm a fan of Topaz's AI Gigapixel. What I've found is generally necessary if I use that program is to cut down the default sharpening in Photoshop when the raw image is opened. Usually the default PS setting is 40. If I leave it there, AIG will then sharpen the halo. Not good. With most of my equipment, if the PS raw conversion sharpening is cut to 20, the halo disappears and Topaz AIG works very well. The lesson seems to be to beware of the "old style" PS sharpening if subsequent processing with AIG is going to be done.
Paul
www.PaulRoark.com
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The automatic setting in Resample picks differing sharpening algorithms just as if you select Automatic in General Preferences (Image Interpolation), so, one for sizing up, one for sizing down and based on the image type. If you leave the interpolation option set to Automatic, Photoshop will automatically select the Preserve Details algorithm when it detects that the user is enlarging the image. When downsampling (reducing) the size of an image, the Automatic option will choose Bicubic Sharper. Of course, you can override this to whatever you desire. Ditto with automatic setting and Free Transform.
Glad to know this level of detail-- I didn't realize it was actually choosing different algorithms-- I kind of hate the "preserve details" look, and I've only ever used Bicubic Sharper for things that are going to printed output which could possibly use the extra sharpening...
As far as non-AI image sampling algorithms are concerned, I still find regular Bicubic (smooth gradients) to be the king of "don't mess with my image" algorithms--