Robert said:
This would limit the application of the contrast masking method on
Photoshop CS, because this is to my knowledge the only imaging
software with 16 bit AND layer support.
That may be possible, although the procedure may also work in PS 7,
Corel PhotoPaint an future versions of PSP and The Gimp.
In my procedure, layers aren't needed anyway.
I have read a lot of discussions about the 16 bit advantages and
there are examples, which show the "sliced" form of a 8 bit picture
histograms, which were stressed with postprocessing steps. But up to
now I have not yet seen a picture comparision, were a clearly visible
advantage can be seen.
You're welcome to try it in 8-bit mode. I have seen unwanted effects,
especially when applying curves with steep inclinations.
Perhaps it is, because my software is Paintshop and not Photoshop,
that I have not completely undersood your explanations yet. What is
the sense if the USM step exactely?
If you don't see halos you can forget about the extra steps anyway.
In my procedure, the mask is an inverted black&white copy of the
picture itself.
The quick mask is a channel that displays your selection, not the whole
image (although it may look like it) in grayscale. Sometimes, the
selection created with 'select color range' results in slightly fuzzy
edges (perhaps an aliasing effect) that may lead to halos when
performing the curves adjustment. By applying the unsharp mask with the
correct settings, you can create sharp transitions where there are meant
to be sharp transitions.
I have to blure this mask in anyway, because the picture would
lose otherwise to much details
By blurring, you can never add or preserve details
- and there the mask can not be
processed by USM.
In Photoshop (not only CS) this is possible. Don't know about PSP.
Is this also your understanding of a contrast mask?
I think it's a different implementation of the same thing.
In the case of batch processing, I apply the contrast masking not to
selections, but to the whole picture. Your step 2, does it refer to
the pichture itself or to the mask?
My procedure is the following: - Duplication of pictire into two
layers - Lower layer is inverted , desaturated and blurred with
Gaussian Blur Filter (40 pixel) - Upper layer blended with "hard
light" - fine tuning of both layers with "Curves"
It seems you are combining my procedure with the standard procedure for
contrast masking. That was not what I meant. My method does not involve
layers, blurring and layer blending modes. I haven't tried the standard
procedure as it is known to produce halos. Anyway, I don't know the PSP
equivalents of my steps 1-5. The purpose of step 2 is to make a
selection that covers the blackest black (=selected foreground color) in
the image completely, the not-so-black blacks partially and does not
cover the midtones nor the highlights. Thus, the deepest shadows are the
most affected by the curves, the not-so-deep-shadows are less affected
and the non-shadows are not affected.
