This article is rated Start-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||||||||||||
|
A recent edit removed all mention of the Purkinje effect, leaving only a link in the See also section to the article. I think it is relevant and useful to mention the Purkinje effect briefly in this article, rather than giving only a link to the article about it. If there are no objections, I propose to restore the content with an added citation to satisfy the fact tag that was placed on the removed content. - Neparis ( talk) 01:28, 6 May 2008 (UTC)
The tungsten MR-16 is shown at wrong color temperature. MR16 filaments are 2700K. At 3700K, tungsten is a liquid. Sadg4000 ( talk) 22:02, 6 June 2009 (UTC)
I think, if the explanation in the article is right, then the chart is wrong:
The explanation says that, at a given (constant) temperature, the "hue" of the ligt varies with the variation of its luminance. Otherhand, in the chart when you go un and down (luminance axis) the color (hue) remains unchanged. I think the color gradient in the chart must be vertical, not horizontal.
If I'm wrong, please tell me. And please excuse my bad english.
Juanmoralesdesign. July 19, 2009.[wrong date] 16:15 (Py local time). —Preceding unsigned comment added by Juanmoralesdesign ( talk • contribs) 20:10, 17 July 2009 (UTC)
I notice someone has reverted the image to the original one with the wrong color temperature for a filament lamp, and a comment about the daylight position which shows they don't understand how the chart works. 81.187.74.206 ( talk) 12:03, 3 August 2011 (UTC)
Kruithof was labeled an "engineer", but he actually was a physicist. After his time at Philips, where he developed fluorescent lighting etc., he was appointed professor of applied physics at Eindhoven University of Technology, researching atomic physics, particularly gas discharges.
-- HHahn (Talk) 13:31, 25 January 2010 (UTC)
What does "pleasing" mean in this context? Which body and light colours are preferred should be subject to personal taste rather than to measurable quantities. Unfortunately, there seems to be no original publication available to ordinary users, so it is not possible to check what Kruithof really meant with this. Could someone with access to Kruithof's PhD thesis or subsequent publication and sufficient Dutch language skills retrieve more information about this?
One could try to understand it in the context of the Purkinje effect, i.e. the shift of the white point for different illuminance levels. However, if whiteness would be the key criterion, 3500-4000 K would be ideal for low light levels since light from type 840 fluorescent lamps appears white, even at levels below 100 lux. Similarly, the Moon has a correlated color temperature of about 4000 K (due to the slightly brownish tone of its surface; otherwise it would have the same CCT as the Sun), and it's light appears dim white, not bluish (however, maybe below the response level of the cones). Incandescent lamps and "warm white" CFLs, however, always have a bias towards a yellowish tone if the the light is cast on a white surface. The Kruithof region of "pleasing" light, however, ranges from about 2500 to 3000 (estimated from the SVG figure), which is well in the yellowish region. At high light levels, however, Kruithof roughly fits, but covers a range from slightly yellowish light to blue skylight. Thus, the Purkinje effect alone cannot explain the Kruithof relation.-- SiriusB ( talk) 14:22, 9 February 2012 (UTC)
From the Criticism section, it appears that Kruithof's curve has been criticised for its unknown methodology, along with other things that seemingly results in questionable reliability on the subject of human preference in relation to CCT and illuminance. These problems seem significant enough to be addressed in the lead section. -- Artoria 2e5 contrib 16:22, 12 March 2017 (UTC)
Hello fellow Wikipedians,
I have just modified one external link on Kruithof curve. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.
This message was posted before February 2018.
After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than
regular verification using the archive tool instructions below. Editors
have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the
RfC before doing mass systematic removals. This message is updated dynamically through the template {{
source check}}
(last update: 5 June 2024).
Cheers.— InternetArchiveBot ( Report bug) 01:38, 13 December 2017 (UTC)
This article is rated Start-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||||||||||||
|
A recent edit removed all mention of the Purkinje effect, leaving only a link in the See also section to the article. I think it is relevant and useful to mention the Purkinje effect briefly in this article, rather than giving only a link to the article about it. If there are no objections, I propose to restore the content with an added citation to satisfy the fact tag that was placed on the removed content. - Neparis ( talk) 01:28, 6 May 2008 (UTC)
The tungsten MR-16 is shown at wrong color temperature. MR16 filaments are 2700K. At 3700K, tungsten is a liquid. Sadg4000 ( talk) 22:02, 6 June 2009 (UTC)
I think, if the explanation in the article is right, then the chart is wrong:
The explanation says that, at a given (constant) temperature, the "hue" of the ligt varies with the variation of its luminance. Otherhand, in the chart when you go un and down (luminance axis) the color (hue) remains unchanged. I think the color gradient in the chart must be vertical, not horizontal.
If I'm wrong, please tell me. And please excuse my bad english.
Juanmoralesdesign. July 19, 2009.[wrong date] 16:15 (Py local time). —Preceding unsigned comment added by Juanmoralesdesign ( talk • contribs) 20:10, 17 July 2009 (UTC)
I notice someone has reverted the image to the original one with the wrong color temperature for a filament lamp, and a comment about the daylight position which shows they don't understand how the chart works. 81.187.74.206 ( talk) 12:03, 3 August 2011 (UTC)
Kruithof was labeled an "engineer", but he actually was a physicist. After his time at Philips, where he developed fluorescent lighting etc., he was appointed professor of applied physics at Eindhoven University of Technology, researching atomic physics, particularly gas discharges.
-- HHahn (Talk) 13:31, 25 January 2010 (UTC)
What does "pleasing" mean in this context? Which body and light colours are preferred should be subject to personal taste rather than to measurable quantities. Unfortunately, there seems to be no original publication available to ordinary users, so it is not possible to check what Kruithof really meant with this. Could someone with access to Kruithof's PhD thesis or subsequent publication and sufficient Dutch language skills retrieve more information about this?
One could try to understand it in the context of the Purkinje effect, i.e. the shift of the white point for different illuminance levels. However, if whiteness would be the key criterion, 3500-4000 K would be ideal for low light levels since light from type 840 fluorescent lamps appears white, even at levels below 100 lux. Similarly, the Moon has a correlated color temperature of about 4000 K (due to the slightly brownish tone of its surface; otherwise it would have the same CCT as the Sun), and it's light appears dim white, not bluish (however, maybe below the response level of the cones). Incandescent lamps and "warm white" CFLs, however, always have a bias towards a yellowish tone if the the light is cast on a white surface. The Kruithof region of "pleasing" light, however, ranges from about 2500 to 3000 (estimated from the SVG figure), which is well in the yellowish region. At high light levels, however, Kruithof roughly fits, but covers a range from slightly yellowish light to blue skylight. Thus, the Purkinje effect alone cannot explain the Kruithof relation.-- SiriusB ( talk) 14:22, 9 February 2012 (UTC)
From the Criticism section, it appears that Kruithof's curve has been criticised for its unknown methodology, along with other things that seemingly results in questionable reliability on the subject of human preference in relation to CCT and illuminance. These problems seem significant enough to be addressed in the lead section. -- Artoria 2e5 contrib 16:22, 12 March 2017 (UTC)
Hello fellow Wikipedians,
I have just modified one external link on Kruithof curve. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.
This message was posted before February 2018.
After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than
regular verification using the archive tool instructions below. Editors
have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the
RfC before doing mass systematic removals. This message is updated dynamically through the template {{
source check}}
(last update: 5 June 2024).
Cheers.— InternetArchiveBot ( Report bug) 01:38, 13 December 2017 (UTC)