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Re: filmscanners: VueScan Histogram
I will add my vote to those VueScan users who do *not* want it to become
an image editing application. I would rather do my tweaks in Photoshop.
But I do encourage Ed to continue development of features which enable
VueScan to save files with the best possible bits. I think a histogram
display is useful for this.
With the current version of VueScan I need to set the white point and
black points by guesswork. I pick a pair of percentage numbers and hope
for the best, or if I have time, I will do a few Prev Mem or Scan Mem
trials to see the effects of various settings. But often, when I bring
the scan into Photoshop and check the histograms, I discover that I
chopped off the highlights or shadows. Or I might have set VueScan's
limits too conservatively, and there are a lot of empty bins in the
histo, with the image data squished into a narrow range of tonal values.
Maybe with more experience I will get better at inspecting VueScan's
displays and choosing the right values for WP, BP, and gamma. But since
these displays are not color managed, I also have to mentally compensate
for how the image appearance is going to change when it goes into
Photoshop. That's a lot for my poor addled brain to handle.
A histogram would help, because the shape of the data distribution is
often more informative than the clip percentages. Ideally, VueScan would
have the tried-and-true histo interface which provides draggable markers
for WP, BP and gamma, with live image updates. But I know Ed does not
like to spend a lot of time implementing complex UI elements that require
platform specific code. If Ed retains the numeric entry UI, I suggest
that the histogram has a calibrated axis for levels (e.g., 0-255 for 8
bit data) and that the WP and BP can be entered using values from this
axis (rather than percentages).
Julian Vrieslander <mailto:email@example.com>