MetamerismPoster

And you thought all you had to worry about was daylight or tungsten…

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LED technology seems poised to cause a revolution in lighting similar to the one we’re just now recovering from in digital cinematography. The sources are becoming increasingly more affordable, more powerful in output, and they sip power while staying cool enough to handle without gloves. They even come in bi-color units so you can change from tungsten to daylight at the flick of a switch. What’s not to love?

Now don’t misunderstand us, we welcome the new lighting revolution. But at Filmtools, we like to think we have your back, so give us a paragraph or two and we’ll give you a lean and mean education in choosing an LED light source. And to do so, we have to take a slight detour into the world of color science.

Color science is full of linear algebra and abstract three dimensional visualizations, the kind of stuff most creatives got into the visual arts to avoid. So don’t panic: we’ll keep the explanations  strictly at the layman level.

When you look at the world, you might think you’re seeing a broad, continuous spectrum of colors. But you’re not. The human retina cheats by sampling three distinct portions of the color spectrum. It samples a portion of red light radiation, a portion of blue light radiation, and a portion of green light radiation. This corresponds to the three type of cone receptors in oSpectrumur retina.

If you look at the graph you’ll see that the cones aren’t very sensitive to cyan wavelength radiation at around 485 nanometers (don’t worry, we don’t need to get into nanometers to make sense of everything). So how is it that we can easily see cyan-colored objects? Well, our brains take the red, blue and green signals the retina is receiving, and combine them to create the perception of cyan light.

So what does this have to do with lighting? Well, what’s important in capturing the color of a scene isn’t actually the faithful reproduction of the physics of light in the scene. It’s more important to capture the scene in a way that mimics the way the human eye sees color. That’s why we use red, green and blue as the primary colors in digital video work. Not because there’s anything magical about those colors in the physics of the universe, but rather because those are the colors that our eyes are sensitive too.

OK, but we still haven’t told you why this matters to lighting. Well here’s the deal: Modern LEDs emit photons (light particles/waves) at a very narrow band of wavelengths. That bandwidth is expanded to a broader set of wavelengths by some phosphor coating voodoo that’s beyond the scope of what we’re covering here. The problem is that the LED lighting doesn’t necessarily cause objects to reflect the right balance of red, green and blue light to the camera, causing color shifts known as metamerism.

How bad is the color shift? It depends on the light. We’ve included a color chart (courtesy of color scientist Alan Roberts) for a poorly performing LED light and you can see the significant shift in color. The outer region of the squares represent how the colors should look, the inner region represents how they illuminate under this particular light source.

So how do you know which LED to choose? Well, you could shoot a Macbeth chart and compare the white-balanced values to tLowEndLEDLightsourcehe accurate values in post, or you can simply look up a rating. Up until recently, color accuracy in lighting has been evaluated using a system called the CRI (Color Rendering Index). The CRI has fallen out of favor however, and a new system is becoming popular: the TLCI (Television Lighting Consistency Index). If a light’s TLCI is 85% or higher, it’s considered to be useful in production with minimal post-production color correction required.

Our recommendations

So should you still think about buying an LED light source? Absolutely: they’re incredibly convenient and becoming more and more affordable. So what should you look for?

First of all, at the affordable end of the price spectrum we recommend you avoid bi-color LED units for general lighting work. Bi-color units tend to have much lower TLCI ratings than their fixed white point counterparts. They also suffer from a much lower luminance output. If you’re looking for a convenient, multipurpose LED to add a little fill to an area of your scene, then a bi-colour LED might be a great option. But if you plan on using your LED as a primary key or fill light, skip the bi-color and choose either a daylight or tungsten balanced unit.

(A quick note: once you move up beyond the $3,000 range, there are bi-colour units that have good TCLI’s for both daylight and tungsten settings. But that’s obviously a much more serious investment.)

 

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LED technology seems poised to cause a revolution in lighting similar to the one we’re just now recovering from in digital cinematography. The sources are becoming increasingly more affordable, more powerful in output, and they sip power while staying cool enough to handle without gloves. They even come in bi-color units so you can change from tungsten to daylight at the flick of a switch. What’s not to love?

Now don’t misunderstand us, we welcome the new lighting revolution. But at Filmtools, we like to think we have your back, so give us a paragraph or two and we’ll give you a lean and mean education in choosing an LED light source. And to do so, we have to take a slight detour into the world of color science.

Color science is full of linear algebra and abstract three dimensional visualizations, the kind of stuff most creatives got into the visual arts to avoid. So don’t panic: we’ll keep the explanations  strictly at the layman level.

When you look at the world, you might think you’re seeing a broad, continuous spectrum of colors. But you’re not. The human retina cheats by sampling three distinct portions of the color spectrum. It samples a portion of red light radiation, a portion of blue light radiation, and a portion of green light radiation. This corresponds to the three type of cone receptors in oSpectrumur retina.

If you look at the graph you’ll see that the cones aren’t very sensitive to cyan wavelength radiation at around 485 nanometers (don’t worry, we don’t need to get into nanometers to make sense of everything). So how is it that we can easily see cyan-colored objects? Well, our brains take the red, blue and green signals the retina is receiving, and combine them to create the perception of cyan light.

So what does this have to do with lighting? Well, what’s important in capturing the color of a scene isn’t actually the faithful reproduction of the physics of light in the scene. It’s more important to capture the scene in a way that mimics the way the human eye sees color. That’s why we use red, green and blue as the primary colors in digital video work. Not because there’s anything magical about those colors in the physics of the universe, but rather because those are the colors that our eyes are sensitive too.

OK, but we still haven’t told you why this matters to lighting. Well here’s the deal: Modern LEDs emit photons (light particles/waves) at a very narrow band of wavelengths. That bandwidth is expanded to a broader set of wavelengths by some phosphor coating voodoo that’s beyond the scope of what we’re covering here. The problem is that the LED lighting doesn’t necessarily cause objects to reflect the right balance of red, green and blue light to the camera, causing color shifts known as metamerism.

How bad is the color shift? It depends on the light. We’ve included a color chart (courtesy of color scientist Alan Roberts) for a poorly performing LED light and you can see the significant shift in color. The outer region of the squares represent how the colors should look, the inner region represents how they illuminate under this particular light source.

So how do you know which LED to choose? Well, you could shoot a Macbeth chart and compare the white-balanced values to tLowEndLEDLightsourcehe accurate values in post, or you can simply look up a rating. Up until recently, color accuracy in lighting has been evaluated using a system called the CRI (Color Rendering Index). The CRI has fallen out of favor however, and a new system is becoming popular: the TLCI (Television Lighting Consistency Index). If a light’s TLCI is 85% or higher, it’s considered to be useful in production with minimal post-production color correction required.

Our recommendations

So should you still think about buying an LED light source? Absolutely: they’re incredibly convenient and becoming more and more affordable. So what should you look for?

First of all, at the affordable end of the price spectrum we recommend you avoid bi-color LED units for general lighting work. Bi-color units tend to have much lower TLCI ratings than their fixed white point counterparts. They also suffer from a much lower luminance output. If you’re looking for a convenient, multipurpose LED to add a little fill to an area of your scene, then a bi-colour LED might be a great option. But if you plan on using your LED as a primary key or fill light, skip the bi-color and choose either a daylight or tungsten balanced unit.

(A quick note: once you move up beyond the $3,000 range, there are bi-colour units that have good TCLI’s for both daylight and tungsten settings. But that’s obviously a much more serious investment.)

 

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LED technology seems poised to cause a revolution in lighting similar to the one we’re just now recovering from in digital cinematography. The sources are becoming increasingly more affordable, more powerful in output, and they sip power while staying cool enough to handle without gloves. They even come in bi-color units so you can change from tungsten to daylight at the flick of a switch. What’s not to love?

Now don’t misunderstand us, we welcome the new lighting revolution. But at Filmtools, we like to think we have your back, so give us a paragraph or two and we’ll give you a lean and mean education in choosing an LED light source. And to do so, we have to take a slight detour into the world of color science.

Color science is full of linear algebra and abstract three dimensional visualizations, the kind of stuff most creatives got into the visual arts to avoid. So don’t panic: we’ll keep the explanations  strictly at the layman level.

When you look at the world, you might think you’re seeing a broad, continuous spectrum of colors. But you’re not. The human retina cheats by sampling three distinct portions of the color spectrum. It samples a portion of red light radiation, a portion of blue light radiation, and a portion of green light radiation. This corresponds to the three type of cone receptors in oSpectrumur retina.

If you look at the graph you’ll see that the cones aren’t very sensitive to cyan wavelength radiation at around 485 nanometers (don’t worry, we don’t need to get into nanometers to make sense of everything). So how is it that we can easily see cyan-colored objects? Well, our brains take the red, blue and green signals the retina is receiving, and combine them to create the perception of cyan light.

So what does this have to do with lighting? Well, what’s important in capturing the color of a scene isn’t actually the faithful reproduction of the physics of light in the scene. It’s more important to capture the scene in a way that mimics the way the human eye sees color. That’s why we use red, green and blue as the primary colors in digital video work. Not because there’s anything magical about those colors in the physics of the universe, but rather because those are the colors that our eyes are sensitive too.

OK, but we still haven’t told you why this matters to lighting. Well here’s the deal: Modern LEDs emit photons (light particles/waves) at a very narrow band of wavelengths. That bandwidth is expanded to a broader set of wavelengths by some phosphor coating voodoo that’s beyond the scope of what we’re covering here. The problem is that the LED lighting doesn’t necessarily cause objects to reflect the right balance of red, green and blue light to the camera, causing color shifts known as metamerism.

How bad is the color shift? It depends on the light. We’ve included a color chart (courtesy of color scientist Alan Roberts) for a poorly performing LED light and you can see the significant shift in color. The outer region of the squares represent how the colors should look, the inner region represents how they illuminate under this particular light source.

So how do you know which LED to choose? Well, you could shoot a Macbeth chart and compare the white-balanced values to tLowEndLEDLightsourcehe accurate values in post, or you can simply look up a rating. Up until recently, color accuracy in lighting has been evaluated using a system called the CRI (Color Rendering Index). The CRI has fallen out of favor however, and a new system is becoming popular: the TLCI (Television Lighting Consistency Index). If a light’s TLCI is 85% or higher, it’s considered to be useful in production with minimal post-production color correction required.

Our recommendations

So should you still think about buying an LED light source? Absolutely: they’re incredibly convenient and becoming more and more affordable. So what should you look for?

First of all, at the affordable end of the price spectrum we recommend you avoid bi-color LED units for general lighting work. Bi-color units tend to have much lower TLCI ratings than their fixed white point counterparts. They also suffer from a much lower luminance output. If you’re looking for a convenient, multipurpose LED to add a little fill to an area of your scene, then a bi-colour LED might be a great option. But if you plan on using your LED as a primary key or fill light, skip the bi-color and choose either a daylight or tungsten balanced unit.

(A quick note: once you move up beyond the $3,000 range, there are bi-colour units that have good TCLI’s for both daylight and tungsten settings. But that’s obviously a much more serious investment.)

 

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Our recommendations

So should you still think about buying an LED light source? Absolutely: they’re incredibly convenient and becoming more and more affordable. So what should you look for? First of all, at the affordable end of the price spectrum we recommend you avoid bi-color LED units for general lighting work. Bi-color units tend to have much lower TLCI ratings than their fixed white point counterparts. They also suffer from a much lower luminance output. If you’re looking for a convenient, multipurpose LED to add a little fill to an area of your scene, then a bi-colour LED might be a great option. But if you plan on using your LED as a primary key or fill light, skip the bi-color and choose either a daylight or tungsten balanced unit. (A quick note: once you move up beyond the $3,000 range, there are bi-colour units that have good TCLI’s for both daylight and tungsten settings. But that’s obviously a much more serious investment.)   [magento-connection sku="Litepanel1x1-etc" /]" } } [10]=> array(4) { ["file"]=> string(117) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/app/themes/filmtoolsblog/templates/content-single.php" ["line"]=> int(13) ["function"]=> string(11) "the_content" ["args"]=> array(0) { } } [11]=> array(4) { ["file"]=> string(91) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/wp/wp-includes/template.php" ["line"]=> int(503) ["args"]=> array(1) { [0]=> string(117) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/app/themes/filmtoolsblog/templates/content-single.php" } ["function"]=> string(7) "require" } [12]=> array(4) { ["file"]=> string(91) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/wp/wp-includes/template.php" ["line"]=> int(477) ["function"]=> string(13) "load_template" ["args"]=> array(2) { [0]=> &string(117) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/app/themes/filmtoolsblog/templates/content-single.php" [1]=> &bool(false) } } [13]=> array(4) { ["file"]=> string(99) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/wp/wp-includes/general-template.php" ["line"]=> int(171) ["function"]=> string(15) "locate_template" ["args"]=> array(3) { [0]=> &array(2) { [0]=> string(33) "templates/content-single-post.php" [1]=> string(28) "templates/content-single.php" } [1]=> &bool(true) [2]=> &bool(false) } } [14]=> array(4) { ["file"]=> string(99) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/app/themes/filmtoolsblog/single.php" ["line"]=> int(1) ["function"]=> string(17) "get_template_part" ["args"]=> array(2) { [0]=> &string(24) "templates/content-single" [1]=> &string(4) "post" } } [15]=> array(4) { ["file"]=> string(97) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/app/themes/filmtoolsblog/base.php" ["line"]=> int(27) ["args"]=> array(1) { [0]=> string(99) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/app/themes/filmtoolsblog/single.php" } ["function"]=> string(7) "include" } [16]=> array(4) { ["file"]=> string(98) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/wp/wp-includes/template-loader.php" ["line"]=> int(74) ["args"]=> array(1) { [0]=> string(97) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/app/themes/filmtoolsblog/base.php" } ["function"]=> string(7) "include" } [17]=> array(4) { ["file"]=> string(85) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/wp/wp-blog-header.php" ["line"]=> int(16) ["args"]=> array(1) { [0]=> string(98) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/wp/wp-includes/template-loader.php" } ["function"]=> string(12) "require_once" } [18]=> array(4) { ["file"]=> string(73) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/index.php" ["line"]=> int(4) ["args"]=> array(1) { [0]=> string(85) "/www/sites/blog.filmtools.com/files/releases/20150421215414/web/wp/wp-blog-header.php" } ["function"]=> string(7) "require" } } ["previous":"Exception":private]=> NULL ["lastResponse"]=> string(69) "{"messages":{"error":[{"code":404,"message":"Resource not found."}]}}" ["debugInfo"]=> NULL }

LED technology seems poised to cause a revolution in lighting similar to the one we’re just now recovering from in digital cinematography. The sources are becoming increasingly more affordable, more powerful in output, and they sip power while staying cool enough to handle without gloves. They even come in bi-color units so you can change from tungsten to daylight at the flick of a switch. What’s not to love?

Now don’t misunderstand us, we welcome the new lighting revolution. But at Filmtools, we like to think we have your back, so give us a paragraph or two and we’ll give you a lean and mean education in choosing an LED light source. And to do so, we have to take a slight detour into the world of color science.

Color science is full of linear algebra and abstract three dimensional visualizations, the kind of stuff most creatives got into the visual arts to avoid. So don’t panic: we’ll keep the explanations  strictly at the layman level.

When you look at the world, you might think you’re seeing a broad, continuous spectrum of colors. But you’re not. The human retina cheats by sampling three distinct portions of the color spectrum. It samples a portion of red light radiation, a portion of blue light radiation, and a portion of green light radiation. This corresponds to the three type of cone receptors in oSpectrumur retina.

If you look at the graph you’ll see that the cones aren’t very sensitive to cyan wavelength radiation at around 485 nanometers (don’t worry, we don’t need to get into nanometers to make sense of everything). So how is it that we can easily see cyan-colored objects? Well, our brains take the red, blue and green signals the retina is receiving, and combine them to create the perception of cyan light.

So what does this have to do with lighting? Well, what’s important in capturing the color of a scene isn’t actually the faithful reproduction of the physics of light in the scene. It’s more important to capture the scene in a way that mimics the way the human eye sees color. That’s why we use red, green and blue as the primary colors in digital video work. Not because there’s anything magical about those colors in the physics of the universe, but rather because those are the colors that our eyes are sensitive too.

OK, but we still haven’t told you why this matters to lighting. Well here’s the deal: Modern LEDs emit photons (light particles/waves) at a very narrow band of wavelengths. That bandwidth is expanded to a broader set of wavelengths by some phosphor coating voodoo that’s beyond the scope of what we’re covering here. The problem is that the LED lighting doesn’t necessarily cause objects to reflect the right balance of red, green and blue light to the camera, causing color shifts known as metamerism.

How bad is the color shift? It depends on the light. We’ve included a color chart (courtesy of color scientist Alan Roberts) for a poorly performing LED light and you can see the significant shift in color. The outer region of the squares represent how the colors should look, the inner region represents how they illuminate under this particular light source.

So how do you know which LED to choose? Well, you could shoot a Macbeth chart and compare the white-balanced values to tLowEndLEDLightsourcehe accurate values in post, or you can simply look up a rating. Up until recently, color accuracy in lighting has been evaluated using a system called the CRI (Color Rendering Index). The CRI has fallen out of favor however, and a new system is becoming popular: the TLCI (Television Lighting Consistency Index). If a light’s TLCI is 85% or higher, it’s considered to be useful in production with minimal post-production color correction required.

Our recommendations

So should you still think about buying an LED light source? Absolutely: they’re incredibly convenient and becoming more and more affordable. So what should you look for?

First of all, at the affordable end of the price spectrum we recommend you avoid bi-color LED units for general lighting work. Bi-color units tend to have much lower TLCI ratings than their fixed white point counterparts. They also suffer from a much lower luminance output. If you’re looking for a convenient, multipurpose LED to add a little fill to an area of your scene, then a bi-colour LED might be a great option. But if you plan on using your LED as a primary key or fill light, skip the bi-color and choose either a daylight or tungsten balanced unit.

(A quick note: once you move up beyond the $3,000 range, there are bi-colour units that have good TCLI’s for both daylight and tungsten settings. But that’s obviously a much more serious investment.)

 

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