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Histofix info required

Posted: Thu Dec 16, 2004 3:21 pm
by ranjan2001
Histo Fix: Like in ColorWasher it fixes a chopped histogram by interpolating lost image information. There is an option to regain 1/2 bit, 1 bit or 2 bit of image information. Works only on 8bit images
Which is better out of 1/2, 1, 2 bits, need some detailed info. I cant use it as an action, is it possible to make it actionable.

Ranjan

Posted: Thu Dec 16, 2004 6:25 pm
by HaraldHeim
Depends on the image, but I would generally recommend 1/2.

Sorry, the plugin isn't actionable.

Posted: Fri Dec 17, 2004 6:29 am
by Guest
[quote="HaraldHeim"]Depends on the image, but I would generally recommend 1/2.
quote]

My understanding is that 2 bits will be better assuming it takes 1 bit info on each side if the histogram & then interpolate the missing info, so why would be 1/2 bit better, need some details how it works.

I am using mostly on full tonal contrats images, such as a landscape with lot of clouds sky green grass.

Posted: Fri Dec 17, 2004 4:09 pm
by HaraldHeim
Honestly, when I developed the Histo Fix stuff I thought it was a nice idea, but I changed my mind in the meantime.

Of course the plugin makes the histogram look "better", but the image looks just like it looked before. There are other operations like resizing, sharpening or noise reduction that fix a histogram, too, as a side effect.

So I would say: It doesn't matter if the histogram looks messed up as long as the image looks fine.

There is only one case where I can imagine that the Histo Fix plugin helps a bit. If an image is already quite degraded and you still need to perform extensive correction on it, the Histo Fix plugin may help to keep the image from degrading further.

If you start from a photo with a "normal" histogram, small gaps can occure in the image after doing some correction. That doesn't really matter, because the image usually looks better after the corrections even if the histogram looks worse.

Generally, I'd say use a low as possible value in the Histo Fix plugin. The Histo Fix essentially dithers the image, so a higher bit value produces a stronger dithering.

Posted: Sun Dec 19, 2004 4:58 am
by Guest
Thanks, that help to know.