Archived posting to the Leica Users Group, 1999/01/19

[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]

Subject: Re: [Leica] "cold" lens rendition
From: Alan Ball <>
Date: Tue, 19 Jan 1999 15:54:03 +0100

Mikiro Mori wrote:

> Also choose your retina. ;-)  Human retinas have substantial variations in
> the cone (color) photoreceptors (RGB).  


Sure, but this seems more like an issue in pre-press workflow
(cooperative work on images and calibration management) than in an
individual's own sense of variation. We probably do not have the same
perception of colours but each of us can normally notice variations
between 2 images, even if we might not qualify those variations in the
same way or notice them to the same degree.

> Changes in a single amino acid of
> the photoreceptors cause shifts of their absorption curves and thus give
> rise to differential hue discrimination.  These variations are hereditary
> but different from "color vision deficiency". ("Color blindness" is not PC.
> ;-))  There is no assuming that you and I have the same color vision.

Would that also explain why perfect humans may recognise a certain color
glow in pictures shot through a certain German gear, even after all
pre-press and press or web procedures have been put to work ? And why
the same perfect humans are fully confident that they recognise
systematic hue variations induced by the glass and coatings used by each
manufacturer of contemporary optical devices ?

I am nothing but a miserable ignorant gnome plagued with accute "color
vision deficiency" and sick photoreceptors, I must admit ;-)

Maybe the Japanese are genetically plagued with the same deficiencies
and that is why they are not able to produce glass and coatings capable
of 'neutral' images: yellow or blue, but not 'neutral'...

Or is it marketing: a group of suppliers caters for the lovers of blue
renditions and another group for the lovers of yellow renditions, all of
them (except one) carefully avoiding 'neutrality'  ?