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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--
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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
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
>>>>>>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
I must agree: single malts solve most problems of our existence on this planet. Creature's Comfort <[EMAIL PROTECTED]> napisał / 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 stój w kolejce do pieniędzy! Sprawdź nową ofertę w Pasażu 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
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
"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
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
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
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
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 .
