What does 'radius' mean in Develop's Detail Refinement routine?

[Peter W Gallagher]

The last thing I do in the raw-conversion part of development (i.e. in Adobe Camera Raw or in AP's Develop module) is capture sharpening. My experience has been that the precise amount of capture sharpening within modest limits isn't critical to the final result. So I just eyeball the result, starting from some slider-values (my own pre-sets in ACR) that have worked in the past.

 

But I'm a bit puzzled by AP's use of a percentage in the Radius slider of Detail Refinement. If this is a USM routine, I'd expect the value in "radius" to be the number of pixels surrounding detected edges where contrast will be increased (by the "amount"). 

 

What does a percentage radius measure? Percent of what?

 

(Or am I wrong to assume that this is a USM routine? Is it, instead, some form of de-convolution?)

 

Thank you.

 

 

 

[lhodaniel]

Great question! I'm unsure of how to use percentage vs pixels as well. I look forward to Affinity's answer on this, and why they chose that parameter.

[James Ritson]

Hi Peter, detail refinement is indeed an unsharp mask filter. The use of percentage rather than pixels for the radius is basically an oversight: at one point, there may have been further designs (e.g. adaptive sharpening), but as it stands, the percentage is simply 1:1 with the pixel radius (so 100% = 100px).

 

Apologies for the confusion and it'll be with the developers to look at. Hope that helps!

[Jowday]

On 3/21/2017 at 1:55 PM, James Ritson said:

Hi Peter, detail refinement is indeed an unsharp mask filter. The use of percentage rather than pixels for the radius is basically an oversight: at one point, there may have been further designs (e.g. adaptive sharpening), but as it stands, the percentage is simply 1:1 with the pixel radius (so 100% = 100px).

Apologies for the confsion and it'll be with the developers to look at. Hope that helps!

Could this please be fixed in 1.8 @James Ritson

[saraartist]

this is somehow still unfixed in V2 however i am just hear bc i am learning and was trying to understand what detail refinement actually does

[LenC]

Just noticed this myself. I'm using Robin Whalley's new ebook on V 2 to help me get my rusty skills refreshed. This easy to fix oversight has continued to be overlooked (oversighted?) for five years and as noted by saraartist is still in V2. Serif should brag about getting it fixed in 2.0.1.

Edited December 12, 2022 by LenC
My equipment and software signature is out of date

[LenC]

Can someone please tell me how I edit my signature? I've wasted half an hour at least looking and searching.

[carl123]

Assuming you are on a desktop

At the top right of the screen click the down arrow next to your avatar/name

Select Account Settings

On the left menu select Signature

 

[LenC]

Thanks, previously went there but did not follow right bread crumbs.

I guess I should not hope that the original issue will be resolved - too trivial.