RE: Completely OT: gripe of the day
Dan Scott said:
Hey! I think I actually understood that explanation.
It would have been even better if I'd said what I meant, namely:
. . . This means that there are several surface materials that
all appear to have the same colour when viewed by one type of sensor
under different light source, but which can have wildly different
colours when viewed by another type of sensor
Is this what I keep seeing referred to as 'metamerism'
Yes - that's one example of metamerism, or colour space aliasing.
John Francis wrote:
Actually it's a great deal more complicated than that. The human
eye, like colour film, is a tristimulus response system - it assigns
a colour to an object based on the total intensity of light measured
by three different sensors, each of which has a response curve that
is more or less sensitive to different frequencies in the spectrum.
Any coloured object, furthermore, reflects some amount of light that
falls on it - more light in the areas of the spectrum that correspond
to the perceived colour of the object; less in other parts. So the
total excitation of the colour sensors is the product ('convolution',
for the mathematically inclined) of the frequency spectrum of the
light source, the reflection curve of the surface, and the response
curve of the sensor. All this boils down to one intensity level.
Obviously there are many combinations of spectrum and refelction
that will yield the same intensity when measured by a particular
sensor. This means that there are several surface materials that
all appear to have the same colour when viewed by one type of sensor
under different light source, but which can have wildly different
colours when viewed under a light source with a different spectrum.
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Re: Completely OT: gripe of the day
Yes, it is... but I've never seen it actually change the color of a dress before. Nick -- From: Keith Zimmerman [EMAIL PROTECTED] To: Pentax [EMAIL PROTECTED] Subject: Re: Completely OT: gripe of the day Date: Fri, Jul 27, 2001, 10:14 PM Date: Wed, 25 Jul 2001 10:10:54 -0500 From: Nicholas Wright [EMAIL PROTECTED] Subject: Re: Completely OT: gripe of the day Once we bought my wife a beautiful green dress at a store only to get home and find that the dress was not, in fact, green; it was brown. We played with it under different lights and found the exact same thing, the dress changed to green when we went to a place with flourescents. weird... - -- DOH! Nick That's because non-filtered flourescent light is green! I have to wear rose-tinted glasses because flourescent light gives me migranes. Keith Zimmerman [EMAIL PROTECTED] http://homepage.dave-world.net/~vkzimm/gallery5.html - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org . - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: Completely OT: gripe of the day
You should see what happened to me once. A couple of months ago I had a slide show at a concert dedicated to Dave Brubeck. The slides were projected on a curtain betweeen the musicians and the public. The wife of the piano man, amongst the public, recorded everything on tape. When I saw the take I couldn't believe to my eyes... The first 30 minutes of the take were normal, and somewhat dull. Then, suddenly, the colors were gone and everything was strange. The musicians were all dressed in black, but in that point of the take only one still had a black shirt and trousers, the others seemed to have changed their dress... Almost all looked like they were dressed in white, or in very light grey (and the scene, although brighter than before, looked normal. Even the skin looked darker than the dresses...). It was like an infrared effect... Gianfranco - Original Message - From: Nicholas Wright [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Saturday, July 28, 2001 4:43 PM Subject: Re: Completely OT: gripe of the day Yes, it is... but I've never seen it actually change the color of a dress before. Nick -- From: Keith Zimmerman [EMAIL PROTECTED] To: Pentax [EMAIL PROTECTED] Subject: Re: Completely OT: gripe of the day Date: Fri, Jul 27, 2001, 10:14 PM Date: Wed, 25 Jul 2001 10:10:54 -0500 From: Nicholas Wright [EMAIL PROTECTED] Subject: Re: Completely OT: gripe of the day Once we bought my wife a beautiful green dress at a store only to get home and find that the dress was not, in fact, green; it was brown. We played with it under different lights and found the exact same thing, the dress changed to green when we went to a place with flourescents. weird... - -- DOH! Nick That's because non-filtered flourescent light is green! I have to wear rose-tinted glasses because flourescent light gives me migranes. __ Do You Yahoo!? Make international calls for as low as $.04/minute with Yahoo! Messenger http://phonecard.yahoo.com/ - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: Completely OT: gripe of the day
Date: Wed, 25 Jul 2001 10:10:54 -0500 From: Nicholas Wright [EMAIL PROTECTED] Subject: Re: Completely OT: gripe of the day Once we bought my wife a beautiful green dress at a store only to get home and find that the dress was not, in fact, green; it was brown. We played with it under different lights and found the exact same thing, the dress changed to green when we went to a place with flourescents. weird... - -- DOH! Nick That's because non-filtered flourescent light is green! I have to wear rose-tinted glasses because flourescent light gives me migranes. Keith Zimmerman [EMAIL PROTECTED] http://homepage.dave-world.net/~vkzimm/gallery5.html - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: Completely OT: gripe of the day
Jaros3aw Brzeziñski wrote: I must agree: single malts solve most problems of our existence on this planet. Didn't good ol' Homer Simpson say something along the lines of, Ah, alcohol, creator and solver of all life's problems? - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: Completely OT: gripe of the day
tom wrote: Life's rough. I'm drinking kirsch, and I pour some for the PDML! Get yourself some single malt and all your troubles will go away. -- Sheldon Belinkoff CREATURE'S COMFORT mailto:[EMAIL PROTECTED] - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: Completely OT: gripe of the day
I really miss a lovely pint of Kilkenny I used to get at the hotel in Simmonds Yat, near the Herefordshire/Monmouth border (Nimbus was the company I worked for). James Richmond BC - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: Completely OT: gripe of the day
Only if you drink lots of it. At 11:27 PM 7/24/2001 -0700, you wrote: tom wrote: Life's rough. I'm drinking kirsch, and I pour some for the PDML! Get yourself some single malt and all your troubles will go away. -- Sheldon Belinkoff CREATURE'S COMFORT mailto:[EMAIL PROTECTED] - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org . - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: Completely OT: gripe of the day
D. Glenn Arthur Jr. wrote: Gripe of the day: picking out an outfit that looks great under incandescent light, only to get to rehearsal and find out that the blues are terribly clashing shades under fluorescent light, and having my self-appointed fashion consultant give me funny looks all evening. How 'bout the pro I know who was shooting sweaters that reflected a very odd and completely different colour from their normal shade under strobes? He got the transparencies back and went and screamed at the lab for a while, who tore their hair out trying to figure out why his trannies were bad but no one else's were...they finally called tech support at Fuji, whose first question was What kind of material was the sweater made out of? Result: apologies all around, followed by a bulk purchase of tungsten balanced film. -Aaron - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: Completely OT: gripe of the day
Once we bought my wife a beautiful green dress at a store only to get home and find that the dress was not, in fact, green; it was brown. We played with it under different lights and found the exact same thing, the dress changed to green when we went to a place with flourescents. weird... -- DOH! Nick -- From: D. Glenn Arthur Jr. [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: Completely OT: gripe of the day Date: Tue, Jul 24, 2001, 11:43 PM (Okay, so it _does_ involve _light_ ... but I don't think even I can stretch on-topic far enough to cover this unless I go off on tangential musings about filters...) Gripe of the day: picking out an outfit that looks great under incandescent light, only to get to rehearsal and find out that the blues are terribly clashing shades under fluorescent light, and having my self-appointed fashion consultant give me funny looks all evening. Looked fine in incandescent and mixed incandescent/sunlight, I swear it! Under fluorescent lights, I looked down and things looked very different from what I'd put on at home. -- Glenn - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org . - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: Completely OT: gripe of the day
I must agree: single malts solve most problems of our existence on this planet. Creature's Comfort [EMAIL PROTECTED] napisa / wrote: tom wrote: Life's rough. I'm drinking kirsch, and I pour some for the PDML! Get yourself some single malt and all your troubles will go away. -- Sheldon Belinkoff CREATURE'S COMFORT mailto:[EMAIL PROTECTED] - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org . --- Nie stj w kolejce do pienidzy! Sprawd now ofert w Pasau Finansowym. Kliknij! http://pasazfin.wp.pl/pasaz/pasaz_bankowy.html?param=inteligo/inteligo_glowna_p.html - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: Completely OT: gripe of the day
Yeah, I couldn't decide between gray or black boxers today. Life's rough. I'm drinking kirsch, and I pour some for the PDML! tv D. Glenn Arthur Jr. wrote: (Okay, so it _does_ involve _light_ ... but I don't think even I can stretch on-topic far enough to cover this unless I go off on tangential musings about filters...) Gripe of the day: picking out an outfit that looks great under incandescent light, only to get to rehearsal and find out that the blues are terribly clashing shades under fluorescent light, and having my self-appointed fashion consultant give me funny looks all evening. Looked fine in incandescent and mixed incandescent/sunlight, I swear it! Under fluorescent lights, I looked down and things looked very different from what I'd put on at home. -- Glenn - - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
