Invert negative scan

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Marameo
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Invert negative scan

Post by Marameo »

Hi,

newbie to ImageMagick. I have a tiff file 16-bit ProPhoto from a color negative scan I would like to invert and autocolor. In Lightroom I have white balanced the film border in order to neutralize the orange mask.

Thanks

snibgo
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Re: Invert negative scan

Post by snibgo »

What version of IM, on what platform? I'll assume v7, on Windows.

I suppose your question is: what IM command will white-balance from the border in order to neutralize the orange mask?

The answer is to crop from the border, and divide the image by that. This will make the border white. Something like this, which assumes the input is 4000x6000 pixels, and a sample from the border is at 50x50+1234+2345:

Code: Select all

magick in.tiff ( +clone -crop 50x50+1234+2345 -scale 4000x6000 ) -compose DivideSrc -composite out.tiff
snibgo's IM pages: im.snibgo.com

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fmw42
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Re: Invert negative scan

Post by fmw42 »

What is your ImageMagick version and platform? Please always provide that, since syntax may differ.

If on a Unix-like system, I have a couple of scripts that would do that. See negative2positive and neg2pos at my link below.

lelldorin
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Re: Invert negative scan

Post by lelldorin »

Negate do the converting

Discused here too: viewtopic.php?t=18681

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