Luminous Landscape Forum

Raw & Post Processing, Printing => Digital Image Processing => Topic started by: bill t. on February 16, 2014, 12:57:07 am

Title: Measure the Color Rendering Index of ambient lighting?
Post by: bill t. on February 16, 2014, 12:57:07 am
Anybody know how to measure the Color Rendering Index of the ambient lighting in an interior space?

In particular, I wonder if there is some way to trick out the i1Pro + i1Profiler combo to come up with a CRI estimate for ambient light.  Or perhaps, a way to photograph a chart in situ and then process that image file somehow.

There are some application specific meters out there, but very expensive and apparently not available for hire anywhere that I know about.

Would appreciate your ideas.  My short term goal is not to design the ultimate exhibit space, but to point out the dismal quality the lighting is in certain existing spaces as a way of encouraging improvement.

CRI in a nutshell (http://ledspots.org/wp-content/uploads/2013/09/CRI.jpg).  When it's YOUR image under CRI 50 conditions, it gets personal.
Title: Re: Measure the Color Rendering Index of ambient lighting?
Post by: MarkM on February 16, 2014, 05:29:30 am
Spotread from the ArgllCMS suite will allow you to measure CRI with an i1pro:
http://argyllcms.com/doc/spotread.html

Easy to use and free.
Title: Re: Measure the Color Rendering Index of ambient lighting?
Post by: digitaldog on February 17, 2014, 09:47:11 am
I use BableColor which provides a number of reports on 'color quality' (quotes because CRI is a bit of a hack in that respect).

http://www.babelcolor.com/main_level/screen_shots/CT&A_ISO3664-1.htm
Title: Re: Measure the Color Rendering Index of ambient lighting?
Post by: Lightsmith on February 27, 2014, 05:04:32 pm
The ambient lighting in galleries is designed to minimize image degradation above all else. It takes priority over optimum lighting for viewing 100% of the time.
Title: Re: Measure the Color Rendering Index of ambient lighting?
Post by: Fine_Art on February 27, 2014, 07:30:46 pm
If you go to the lamp manufacturer websites GE, Sylvania, etc., you can find their spec sheets for their bulbs.