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Re: ICC profile for a light box

Cross-posted to 3 groups.

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On 01/08/2018 01:24, Eric Stevens wrote:
> On Tue, 31 Jul 2018 06:01:58 -0700, Savageduck
> <savageduck1@{REMOVESPAM}me.com> wrote:
> 
>> On Jul 31, 2018, dale wrote
>> (in article <bfm11i.dud.17.2@news.alt.net>):
>>
>>> On 7/30/2018 9:57 PM, nospam wrote:
>>>> In article<bfl4oa.9ei.19.3@news.alt.net>, dale<dale@dalekelly.org>
>>>> wrote:
>>>>
>>>>> might be a nice feature for Lightroom ... compatible with some
>>>>> measurement instruments ... and data like viewing angle, white point, etc.
>>>>
>>>> lightroom has been fully colour managed since day one.
>>>
>>> there is a difference between managing color and managing appearance,
>>> look up CIECAM02 on wikipedia
>>>
>>> viewing environment like a light room is one variable in appearance
>>
>> What exactly do you believe is a *light room*?
>>
>> Understand that any viewing environment is going to be influenced by amient
>> light, regardless of the specific light source be it day light, or any type
>> of artificial lighting.
>>
>> What is your specific, or special purpose/interest for needing this specific
>> icc profile for a *light room* (not LR the app)?
>>
>> It doesn’t sound as though you have any interest in color management for
>> photography post processing.
> 
> My impression is quite the contrary. Why else do you need color
> management if it is to enable the management and control of the
> appearance of the finished print? The process starts with the object,
> continues through the camera, the processing in computer (which
> includes the screen or monitor), on through the printer and paper and
> surely (and this is the subject of the OP's original post) includes
> the viewing environment.

Provided that the light approximates a blackbody with a characteristic 
temperature then the human eye's automatic white balance does a very 
good job of removing the orange or blue casts that a camera will 
faithfully record (if it is set to record the absolute RGB image). 
Remember in the old days of daylight vs artificial light films?

You cannot control the lighting environment that prints will be viewed 
in and some peaky LED or mercury line fluorescent lamps can mess stuff 
up. But if you avoid the obvious pitfalls then comparison by eye with 
the original object is OK under real incandescent light or sunlight.

There are a handful of materials whose colours alter radically depending 
on the colour temperature of the light that they are seen in didymium 
glass being one such and the gemstone Alexandrite another. They are 
unusual in that they have a deep cut notch in their transmission 
spectrum in the yellow which makes their perceived (and measured) colour 
vary significantly with the ambient lighting characteristics.

https://en.wikipedia.org/wiki/Chrysoberyl#Alexandrite

Most pigments and dyes used in colour printing avoid having these 
characteristics to prevent a print from appearing significantly 
different depending on the colour temperature of the ambient light.

You still have problems in a mixture of incandescent and daylight though 
if the proportions vary across the object. Compared to the subjective 
errors caused by well known optical illusions there is little point in 
obsessing about total control of everything for one particular lighting 
situation unless you can control the display environment precisely.

-- 
Regards,
Martin Brown

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Thread

ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-25 06:02 -0400
  Re: ICC profile for a light box nospam <nospam@nospam.invalid> - 2018-07-25 07:38 -0400
    Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-25 08:33 -0400
      Re: ICC profile for a light box nospam <nospam@nospam.invalid> - 2018-07-25 11:21 -0400
        Re: ICC profile for a light box Eric Stevens <eric.stevens@sum.co.nz> - 2018-07-26 12:43 +1200
    Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-30 19:44 -0400
      Re: ICC profile for a light box Savageduck <savageduck1@{REMOVESPAM}me.com> - 2018-07-30 17:31 -0700
        Re: ICC profile for a light box Savageduck <savageduck1@{REMOVESPAM}me.com> - 2018-07-30 17:33 -0700
          Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-30 21:49 -0400
            Re: ICC profile for a light box nospam <nospam@nospam.invalid> - 2018-07-30 21:57 -0400
              Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-31 05:52 -0400
                Re: ICC profile for a light box Savageduck <savageduck1@{REMOVESPAM}me.com> - 2018-07-31 06:01 -0700
                Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-31 09:58 -0400
                Re: ICC profile for a light box nospam <nospam@nospam.invalid> - 2018-07-31 10:06 -0400
                Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-31 10:22 -0400
                Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-31 10:30 -0400
                Re: ICC profile for a light box Savageduck <savageduck1@{REMOVESPAM}me.com> - 2018-07-31 07:46 -0700
                Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-31 11:59 -0400
                Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-31 20:35 -0400
                Re: ICC profile for a light box Eric Stevens <eric.stevens@sum.co.nz> - 2018-08-01 12:24 +1200
                Re: ICC profile for a light box Martin Brown <'''newspam'''@nezumi.demon.co.uk> - 2018-08-02 09:54 +0100
                Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-08-02 15:48 -0400
                Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-08-05 14:31 -0400
            Re: ICC profile for a light box Savageduck <savageduck1@{REMOVESPAM}me.com> - 2018-07-30 19:07 -0700
              Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-31 05:51 -0400
        Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-30 21:45 -0400
          Re: ICC profile for a light box nospam <nospam@nospam.invalid> - 2018-07-30 21:46 -0400
            Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-31 05:52 -0400
              Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-31 07:07 -0400
            Re: ICC profile for a light box PeterN <"peter,newdelete"@deleteverizon.net> - 2018-08-02 18:28 -0400
      Re: ICC profile for a light box nospam <nospam@nospam.invalid> - 2018-07-30 21:31 -0400
        Re: ICC profile for a light box dale <dale@dalekelly.org> - 2018-07-30 21:47 -0400
        Re: ICC profile for a light box Eric Stevens <eric.stevens@sum.co.nz> - 2018-08-01 12:28 +1200
          Re: ICC profile for a light box nospam <nospam@nospam.invalid> - 2018-07-31 20:59 -0400

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