View Single Post
  #30  
Old September 15th 14, 08:59 PM posted to rec.photo.digital
nospam
external usenet poster
 
Posts: 24,165
Default Lenses and sharpening

In article , Floyd L. Davidson
wrote:

UnSharpMask is not reversible.

it is with a non-destructive workflow.

I'm sorry that you don't understand the meaning of that.


i absolutely do know the meaning, since it's all i use.

it's you who doesn't understand what a non-destructive workflow means


A non-destructive workflow means you can *undo* and then *redo*.

That is not a reversible function.


it is to the user, which is what matters.

in other words, the user sharpens today and then tomorrow or next month
or whenever, they can readjust it or remove it entirely. that means to
the user, it's reversible.

that's why a non-destructive workflow is so powerful.

For example, you can add sharpening with a high pass
sharpen tool to an image, save it as a JPEG, send it to
someone else, and they can use a blur tool to reverse
the sharpen.


not perfectly. you even said 'virtually reverses' in your description.

that's another way of saying 'there is some loss.'

In article , Floyd L. Davidson wrote:
Not the case. It is the high pass sharpen tool that is the inverse of
blur. They can use the exact same algorithm with different parameters.
Using one and then the other virtually reverses the results.



If the sharpening is done with UnsharpMask that cannot
be done. USM is not reversible.


in a destructive workflow that is true.

in a non-destructive workflow, it is not true.