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From: "Joris" <joris.at.lebbeke@skynet.be>
To: "Bob Friesenhahn" <bfriesen@simple.dallas.tx.us>
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	<Pine.SOC.4.60.0612051056470.13644@blade.simplesystems.org>
Subject: Re: [Tiff] Grayscale, or is it?
Date: Tue, 5 Dec 2006 18:34:51 +0100
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Status:   

Bob,

Bob Friesenhahn wrote:
> For scientific/sensing applications, grayscale can mean almost
> anything, but for most of the world grayscale is Rec.601 Luma with
> gamma = 1/2.2.  That is because grayscale for TVs came first and color
> was added later.  For modern computer and HDTV displays, Rec.709 Luma
> is more appropriate, but it is still based on gamma = 1/2.2.

In other words, if you need to display the TIFF greyscale on an sRGB
monitor, then you're not applying any gamma correction to it, which is
consistent LibTiff RGBA interface implementation, and very likely
consistent with 95% of common practice out there?

Do you agree that this most common practice violates the quoted remark
from the spec?

(I'm not being religious about the spec here, I'm merely trying to sort
things out and arrive at a consensus in the mailing list and mailing
list archive.)


Best regards,

Joris Van Damme
info@awaresystems.be
http://www.awaresystems.be/
Download your free TIFF tag viewer for windows here:
http://www.awaresystems.be/imaging/tiff/astifftagviewer.html

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