From: "Aart Kooijman" <a.c.kooijman@med.rug.nl>
Organization: faculty of medical sciences (RuG)
To: Color and Vision Network <cvnet@lawton.ewind.com>
Subject: Re: CVNet - query on interpretation of color vision tests
Dear Gene,
You do not specify the type of fluorescent tubes that were used. That
information is essential to understand your results.
Fluorescent tubes vary very much in colour, due to the number of
phosphors in the tube. Modern fluorecscent tubes are available with
good and very good colour reproduction qualities. For instance,
colour tests can be performed with the use of the Philips 960.The
number 9 indicates a colour reproduction score between 90-100 on a
scale of 0-100. Classical fluorescent tubes score between 30-40. The
number 60 indicates a colour temperature of about 6000K, which
corresponds with day light. I guess that your results on the colour
test will normalise if you used a fluorescent tube with comparable
specifications.
Best wishes
Aart Kooijman
> From: Gene4@aol.com
> Subject: Assistance Requested
> To: cvnet@lawton.ewind.com
>
> I would appreciate assistance from the group. The test results below are
> from two individuals applying to become police officers. The indoor tests
> were given in March. The Outdoor tests given in May.
>
> Three color vision tests were given to two persons: Ishihara, Farnsworth
> D-15 and Lanthony 15 Hue. Both were desaturated panel tests.
>
> The Ishihara and Farnsworth were administered in an office under florescent
> lighting and outside in sunlight. The Lanthony in sunlight only.
>
> Person 1 Results:
>
> INDOOR Florescent Lighting:
> Isihara: Unknown: Results recorded as "fail."
> Farnsworth: 1, 2, 15, 3, 14 4 ,13, 5, 12, 11, 6, 10, 7, 9, 8
>
>
> OUTDOOR Sunlight
> Ishihara: 17 out of 17 correct
> Farnsworth: Perfect Score
> Lanthony: 1,15,2,14,5,13,12,4,5,11,10,6,9,7,8
>
> The test is being used in an employment process. The Lanthony was given due
> to concerns the individual might have obtained a Farnsworth to practice on.
> I suspect this person wore an x-chrom lens that was undetected during the
> test (the physician did not check). Is there another explanation for these
> scores?
>
> Person 2 Results
>
> INDOOR Florescent Lighting:
> Isihara: 1 out of 7 plates correct.
> Farnsworth: 1, 15, 2, 14, 3, 13, 4, 5, 12, 11, 6, 10, 7, 9, 8
>
>
> OUTDOOR Sunlight
> Ishihara: 17 out of 17 correct
> Farnsworth: Perfect Score
> Lanthony: Perfect Score
>
> Is it possible to have obtained results like this without cheating on the
> test with an x-chrom lens?
>
> Gene Carmean
> GCarmean@med-tox.com
> www.med-tox.com
>
>
================================================================
ECVP2000 (The European Conference on Visual Perception) will be held in
Groningen,
The Netherlands from 27-31 August 2000. Info: http://ecvp.org/
=================================================================
Prof.Dr. Aart C. Kooijman
Visio chair of Videology
Editor of Visual Impairment Research (http://www.swets.nl/sps/journals/vir1.html)
===============================================
Laboratory of Experimental Ophthalmology (LEO)
School of Behavioral and Cognitive Neurosciences (BCN)
Hanzeplein 1, 9713 GZ Groningen
P.O.Box 30 001, 9700 RB Groningen, The Netherlands
tel. +31 (0)50 3612165, fax +31 (0)50 3611636
This archive was generated by hypermail 2b29 : Tue May 30 2000 - 10:12:07 PDT