paint mixing, named colors

On 04/20/2015 01:26 AM, isw wrote:
Look up "metamerism".

yes ... you could do mixing from spectral data to avoid metamerism


--
Dale
http://www.dalekelly.org

In article , Dale
wrote:

On 04/20/2015 01:26 AM, isw wrote:
Look up "metamerism".

yes ... you could do mixing from spectral data to avoid metamerism

But it would be *really difficult* if you could not identify the
specific colorants from their spectra (impossible?). And, of course,
you'd be unlikely to have every possible item on hand anyhow.

Possible in theory, not very likely in practice.

Isaac

On 04/24/2015 11:44 PM, isw wrote:
In article , Dale
wrote:

On 04/20/2015 01:26 AM, isw wrote:
Look up "metamerism".

yes ... you could do mixing from spectral data to avoid metamerism

But it would be *really difficult* if you could not identify the
specific colorants from their spectra (impossible?). And, of course,
you'd be unlikely to have every possible item on hand anyhow.

Possible in theory, not very likely in practice.

Isaac


colorimetry alone would get you to "good enough color", accurate enough
too edit from

--
Dale
http://www.dalekelly.org

In article , Dale
wrote:

On 04/24/2015 11:44 PM, isw wrote:
In article , Dale
wrote:

On 04/20/2015 01:26 AM, isw wrote:
Look up "metamerism".

yes ... you could do mixing from spectral data to avoid metamerism

But it would be *really difficult* if you could not identify the
specific colorants from their spectra (impossible?). And, of course,
you'd be unlikely to have every possible item on hand anyhow.

Possible in theory, not very likely in practice.

Isaac


colorimetry alone would get you to "good enough color", accurate enough
too edit from

Under very controlled lighting, true.

Isaac

On 26/04/2015 05:00, isw wrote:
In article , Dale
wrote:

On 04/24/2015 11:44 PM, isw wrote:
In article , Dale
wrote:

On 04/20/2015 01:26 AM, isw wrote:
Look up "metamerism".

yes ... you could do mixing from spectral data to avoid metamerism

But it would be *really difficult* if you could not identify the
specific colorants from their spectra (impossible?). And, of course,
you'd be unlikely to have every possible item on hand anyhow.

Possible in theory, not very likely in practice.

Isaac


colorimetry alone would get you to "good enough color", accurate enough
too edit from

Under very controlled lighting, true.

Isaac

As a part of the UK National Gallery's "Making Colour" exhibition last
year they had an old master and a fake exactly matched for 2700K
incandescent room lighting in a lecture room where the lighting
conditions could be varied to simulate everything from natural full
sunlight to fluorescent lamps. The experiment which involved public
participation isn't shown on summary which concentrates only on the
exhibits in the exhibition rather than the modern demo forgery.

http://www.nationalgallery.org.uk/wh.../making-colour

Part of the interactive test was to determine proportion of people who
were colour blind and to what extent and then who could see what. There
were startling differences between the two under the right lighting.

--
Regards,
Martin Brown