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Thread: High CRI and its significance

  1. #121
    *Flashaholic* McGizmo's Avatar
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    Default Re: High CRI and its significance

    Hi guys,
    I got the color checker yesterday. I don't know if the colored squares are on cardboard or not but the squares are captive in a thin black frame which is solid black on the back side. The assembly looks pretty nice to me and the flat, non reflective surfaces of the colored squares is also very nice! I believe all things considered, the price was worth it. I have taken a couple pictures but before I post anything, i want to play with these some more and get a better feel for what might be worthy of posting beyond just a picture of the color checker!

    There is a small guide pamphlet that comes with the checker and it alone has a bunch of information including the RGB constituents for each square so in PhotoShop, for instance, you could likely duplicate these colors. I don't think these are going to turn out to be tight and band specific but won't have a feel for this until I sample them with the spectrometer which I will do later on when I get a chance.

    There is mention of some squares that will change if your light source has problems and this supports the fact that these squares are not a single band. The squares are named and in the naming itself, I think I see a problem for me!! There is a "blue flower" which doesn't jibe with my perception. The blue flower looks more like a lavender or blue/purple to me. I will be curious if younger eyes see this color with the blue in it's namesake?!?! If yes, this may point to the yellow tint of my eyes and why I prefer more blue in my light to overcome the yellow?!?!

    Here is the ColorChecker under bright direct sunlight. In fact it was so hot and the deck was so hot that the Color Checker started to curl up like a potato chip and I took it out of the sun quickly!



    The squares are numbered from left to right, top row and then next row and then next row. The Blue Flower is #5. #1 is titled dark skin and #2 is called light skin. The notes say that #13 which is blue will turn purple easily if there is too much red in the lighting.

    My guess at the best means of comparing this checker under different lights would be to get the camera exposure off one of the gray squares for the various shots to insure a similar saturation from shot to shot. You photo experts may have a better idea.
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  2. #122
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    Default Re: High CRI and its significance

    It's not your eyes. Square 5 looks like lavender to me also. However, like you I have a preference for bluer light.

  3. #123
    *Flashaholic* McGizmo's Avatar
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    Default Re: High CRI and its significance

    Quote Originally Posted by iconoclast View Post
    ...
    I noticed this fixture which seems to be using sixteen of the high-cri nichia 083 for room lighting.
    Cree's response seems to be this light which claims to produce 650 lumens with a cri of 92. I'm curious if either of these live up to their promise as room lighting that doesn't make your guests look like zombies?
    I meant to respond to this and failed to do so. The 083 fixture looks pretty cool and reading the spec page is refreshing because it sounds like these guys are on the ball and addressing the concerns as they should be addressed?!?

    I don't think guests would look like zombies under these lights.
    Build Prices .... some mods and builds (not 4 sale) "Nature can be cruel- but we don't have to be."~ Temple Grandin

  4. #124

    Default Re: High CRI and its significance

    We have a bunch of those color cards where I work and I don't think we pay $75 for them (but it's still a surprisingly large amount, maybe $40 or something). We use the small ones that are about 2x3 inches IIRC. We are getting some overcast lately so I may try taking a picture of one in overcast sunlight. I guess there's no overcast where Don is.

    jtr1962 is right, the wavelengths coming off of these cards when illuminated by continuous spectrum light don't exist in the output of computer monitors or RGB led sources.

    Yes, setting exposure with a grey card (or one of the grey squares if you don't have a grey card but have a spot meter) is the right approach.

  5. #125

    Default Re: High CRI and its significance

    setting exposure with a grey card
    My Kodak 18% gray card is still in the camera bag ... pretty handy when you (or your digi-camera's internal algorithm) cannot quite get it right. I saw a neat article that suggested that 12% is closer to correct, as the ANSI meter calibration standard is roughly that.

    http://www.bythom.com/graycards.htm


    I don't think we pay $75 for them
    The Mini version, like you use, is around $50.

    get the camera exposure off one of the gray squares for the various shots to insure a similar saturation from shot to shot.
    That sounds correct to me. As long as you have identical reflectance (all else being equal) the exposures will be identical. You may run into some color variation as your shots are compared to other people using different cameras but using the same LED light source. As I understand it, the photo receptors in different brands of camera, and even in different models within the same brand, have different spectral response curves - just as with each brand or model light meter. To add to the confusion, the programmed camera algorithm that interprets spectral response can/may/will cause the photo to look different than your eyes see it. Then your spectrometer comes into play, and you should be able to read the wavelength (nm) of the reflected light.

    By adjusting the camera's color balance, you should be able to produce a photo (which includes the color card) where both the photo & the actual appearance are a close match.
    Last edited by precisionworks; 06-19-2008 at 08:48 AM.
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  6. #126
    Flashaholic* BigHonu's Avatar
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    Default Re: High CRI and its significance

    Blue flower looks lavender to me as well.

    I get that weird optical illusion where there is a light grey circle at the intersections of the black lines.....

    Interested to see how the LEDs in the LS20 fair.



    Nice deck BTW. Redwood?
    Last edited by BigHonu; 06-19-2008 at 01:36 PM.

  7. #127

    Default Re: High CRI and its significance

    There is a humorous side to all this ...

    Half the 'problem' with photography today is the digital media. It is so easy to PhotoShop any picture (even attaching a politician's head to a horse's posterior, which is somewhat OT). Way back when, all the best color photography was done with Kodak Ektachrome 25, Fuji Velvia, etc. Every lab in the world used the same identical chemistry to process slide film. If you shot a color card at high noon (6000k) in Maui, & I shot a color card at high noon in Illinois, both slides would contain the same colors with the same color saturation (assuming identical exposure).

    Today, the variable (in addition to exposure & color temperature of the light source) is the digital media.

    Interesting article on CRI here:

    http://www.ledinsider.com/LEDUnivers...ing_Index.aspx
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  8. #128
    Moderator js's Avatar
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    Default Re: High CRI and its significance

    Quote Originally Posted by jtr1962 View Post
    Can someone more knowledgeable about color gamuts than me chime in here? It seems to me a display device can only the display the colors within its color gamut, and some (most?, all?) might not be able to display all the colors in the color checker.
    For starters you left off the other part of my response about how someone might use the color checker--to make two different photo sessions with different cameras under different conditions look the same.

    Next, a display device has limits, yes, but you can adjust things for a best match for your eyes and display device. It's what everyone does these days with digital photos in iPhoto or photoshop or whatever. They take a pic with a digital camera, then upload photos, then go "Hmmm. That looks a bit off to me. I think I'll adjust this and that to make it look more like what I think is right." The only difference here is that you've got a true standard on hand that has a nice wide range of color squares specially designed for the application.

    But, we will be doing the opposite, really. We will be taking two light sources and comparing the color checker images against each other on the same display device.

    As for some of the squares looking different under different light sources, I imagine that some colors just can't be made band-specific. Maybe they need a nice broad spectral peak. Even so, I presume that all of the color squares will have only one peak even if it is broad.
    -Jim Sexton, creator of the M6-R, the TigerLight Upgrades, Fixture-ring lamp potting, the SL60, co-designer of the B90 Upgrade, and proponent of the SF A2, the SF M6 X-LOLA, Titanium, the Haiku, and the LunaSol 20

  9. #129

    Default Re: High CRI and its significance

    The purple and lavender squares will have at least two peaks, one in the blue spectrum, and one in the red. I'm not sure how many peaks the "light and dark skin tone" squares will have, but I'll bet it's more than 1. The color changing blue #13 also must have a peak in blue with some reflectance (smaller peak?) in red to perform as described.

  10. #130
    Moderator js's Avatar
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    Default Re: High CRI and its significance

    Quote Originally Posted by mahoney View Post
    The purple and lavender squares will have at least two peaks, one in the blue spectrum, and one in the red. I'm not sure how many peaks the "light and dark skin tone" squares will have, but I'll bet it's more than 1.
    I bet that's not the case, but we'll see what Don's spectrometer tells us and know for sure! If you take sunlight and a prism, the rainbow of colors extended over the whole visible spectrum, and includes purple, for example. Light at a single, specific wavelength, and not a two-peak wide-spectrum light. A pigment can be the same. If its reflectance peaks at the frequency for purple, then it's purple. Of course, most purple isn't done that way. Which is why it will look different under different lights as seen in the pictures Don posted in this thread. But that's why the color checker is special.

    Or at least this is my understanding of this situation, these things. Perhaps I am mistaken. It will be interesting to see how this unfolds.

    The color changing blue #13 also must have a peak in blue with some reflectance (smaller peak?) in red to perform as described.
    Yes. Totally agree with this, but this is the only square that is mentioned to have this property, right? Don? Anyone?

    And if so, the fact that they specfically mention this for this one square implies the others aren't like this.

    I presume/assume/guess, anyway. Perhaps I'm wrong. I'm very interested to see the results of this, and to play with a color checker myself.
    Last edited by js; 06-20-2008 at 01:26 PM.
    -Jim Sexton, creator of the M6-R, the TigerLight Upgrades, Fixture-ring lamp potting, the SL60, co-designer of the B90 Upgrade, and proponent of the SF A2, the SF M6 X-LOLA, Titanium, the Haiku, and the LunaSol 20

  11. #131
    *Flashaholic* McGizmo's Avatar
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    Default Re: High CRI and its significance

    Hi guys,
    I am holding off until I get a new reference light from Ocean Optics. With this light, I will be able to configure my spectrometer for relative measures. I'll capture some spectrums off the color checker at that time.
    Build Prices .... some mods and builds (not 4 sale) "Nature can be cruel- but we don't have to be."~ Temple Grandin

  12. #132
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    Default Re: High CRI and its significance

    Quote Originally Posted by iconoclast View Post
    Other than Don's SunBar and MeatLight, has anyone had the opportunity to check out fixtures or other light groupings with a cri emphasis?
    I noticed this fixture which seems to be using sixteen of the high-cri nichia 083 for room lighting.
    Cree's response seems to be this light which claims to produce 650 lumens with a cri of 92. I'm curious if either of these live up to their promise as room lighting that doesn't make your guests look like zombies?
    Based on my experiences with Cree's warm phosphors, these fixtures will be huge hits when they come down in price. The capability is fully there, but $120/can is too high for mainstream.

  13. #133

    Default Re: High CRI and its significance

    I'll be interested to see the results as well. "Purple light" was a favorite topic of discourse for our former lighting faculty member. The visible spectrum covers violet, and depending on where you draw the line on what's "purple" that covers some of them, but a lot (probably most) of purples are a combination of red and blue.

  14. #134
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    Default Re: High CRI and its significance

    A very practical reason why most purples are mixes of red and blue is due to the higher sensitivity of your eye to those colors. Red light at 640 nm and blue light at 470 nm have a luminous efficacy of perhaps 60 lm/W. Purple light at 395 nm is well under 1 lm/W. My guess is few purple objects reflect only purple light. Except under very high intensity light, such objects would always appear very dark.

  15. #135
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    Quote Originally Posted by js View Post
    For starters you left off the other part of my response about how someone might use the color checker--to make two different photo sessions with different cameras under different conditions look the same.
    Yes, these can also serve that purpose. It's a matter of artistic tastes however whether or not you would actually want to do this. I prefer to leave my pictures as my eye sees them. For example, things shot under incandescent with the white balance set to sunlight appear yellow. This is exactly how they appear to my eyes. It's how I want them to look because they reflect my reality better. And sometimes a picture being off-color is done on purpose to set a mood. There was one movie where a lot of this was done. Forgot the name but the plot involved a couple on a cross-country killing spree.

    Next, a display device has limits, yes, but you can adjust things for a best match for your eyes and display device. It's what everyone does these days with digital photos in iPhoto or photoshop or whatever. They take a pic with a digital camera, then upload photos, then go "Hmmm. That looks a bit off to me. I think I'll adjust this and that to make it look more like what I think is right." The only difference here is that you've got a true standard on hand that has a nice wide range of color squares specially designed for the application.
    I spent a couple of days fiddling around with my LCD monitor when I bought it about 2 years ago. No idea if I ever got the color as good as it could be, but I remember doing RGB gamma adjustments and also something with gray squares. Most monitors from the factory are way too bright for starters. And the colors are adjusted to be too vivid. I'm pretty happy with the adjustments I made, but I still have no idea whether or not they're actually as accurate as possible for my monitor. Taking pictures of color checkers or other objects won't help much here either since the response of the camera enters into the equation.

  16. #136

    Default Re: High CRI and its significance

    Quote Originally Posted by McGizmo View Post
    ...
    The 083 fixture looks pretty cool and reading the spec page is refreshing because it sounds like these guys are on the ball and addressing the concerns as they should be addressed?!?
    It seems promising anyway. In all fairness, they actually have three variants of the fixture, differing in the choice of led. So you can choose between bright, color rendition, or lower price. But at least they're on the ball enough to offer the choice. Hopefully, at the rate leds seem to be progressing, it won't be long before you don't have to choose.

    Quote Originally Posted by McGizmo View Post
    I don't think guests would look like zombies under these lights.
    Oh good. Once I have a bunch of these installed, anyone who still looks like a zombie has some explaining to do!

    I guess I should explain that one of my co-workers attempted awhile back to be a very early adopter of then bleeding edge led lighting bulbs/fixtures only to discover that it made everyone "look dead". I was showing him the SunDrop, and the discussion turned to it's output vs. typical lighting fixtures, which in turn led to the google searches that turned up the fixtures I mentioned. I was hoping someone has some first hand experience with these, but I also don't know how much vapor is contained in that product description.

    Quote Originally Posted by LukeA View Post
    Based on my experiences with Cree's warm phosphors, these fixtures will be huge hits when they come down in price.
    The capability is fully there, but $120/can is too high for mainstream.
    ouch. yeah, that'll have to come down a bit for them to catch on, I suspect. But at least they're likely to do so reletively quickly (assuming they follow the same overall trends the led market as a whole seems to be doing.)

    Some of the earlier posts suggested that the Seoul entrant wasn't yet quite what we might have hoped it to be, (which for purposes of this discussion means "at least as good as a SunDrop",) so it's good to hear that some of the other contenders hold some promise of competition.
    Can't wait to see these becoming available, and hopefully soon, affordable.
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  17. #137
    Flashaholic* adamlau's Avatar
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    Default Re: High CRI and its significance

    Quote Originally Posted by precisionworks View Post
    [i1Display 2 is] a pretty cool program ... eager to see your results.
    Calibrated multiple times to ensure repeatable results. Very interesting reults is what I have to say. 6500K, 2.2, 120 required the following adjustments to the LCD defaults of a SyncMaster 906cw:

    Brightness: 100 to 12
    Contrast: No Change (75)
    Red: 50 to 46
    Green: No Change (50)
    Blue: No Change (50)

    Definitely warmer all around, grays appear to be impacted the most. Being used to a cooler rendition of 6500K, this new profile will take some time getting used to. The software was intuitively easy to use, the tutorials are helpful. Now to calibrate the rest of the monitors in the house (one iMac, two ThinkPads and a ViewSonic G225fB). Very nice .

    UPDATE:
    Did a very good job on a pair of matte ThinkPads and a great job on a Gateway glossy. The monitor which showed the most improvement thus far? An iMac 20-inch glossy. The G225fB and a Dell 2408WFP are up next...
    Last edited by adamlau; 06-21-2008 at 04:48 AM.
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  18. #138
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    Default Re: High CRI and its significance

    Quote Originally Posted by jtr1962 View Post
    Yes, these can also serve that purpose. It's a matter of artistic tastes however whether or not you would actually want to do this. I prefer to leave my pictures as my eye sees them. For example, things shot under incandescent with the white balance set to sunlight appear yellow. This is exactly how they appear to my eyes. It's how I want them to look because they reflect my reality better. And sometimes a picture being off-color is done on purpose to set a mood. There was one movie where a lot of this was done. Forgot the name but the plot involved a couple on a cross-country killing spree.
    The idea was for cases where the result is clearly NOT the way your eye saw them at the time the picture was taken. The color checker allows a more precise adjustment in these cases, and allows for consistency across platforms and shoots.

    I spent a couple of days fiddling around with my LCD monitor when I bought it about 2 years ago. No idea if I ever got the color as good as it could be, but I remember doing RGB gamma adjustments and also something with gray squares. Most monitors from the factory are way too bright for starters. And the colors are adjusted to be too vivid. I'm pretty happy with the adjustments I made, but I still have no idea whether or not they're actually as accurate as possible for my monitor. Taking pictures of color checkers or other objects won't help much here either since the response of the camera enters into the equation.
    This is nonsense, jtr. The fact that the camera enters into the equation, and the monitor, and the printer, and whatever else, is the very reason WHY THE COLOR CHECKER IS NEEDED. At the start of things, you know what you had: the color checker squares, which behave in a known reliable way. At the end of things, wherever that may be--a printout, a screen image, film, whatever--you make the image of the color checker as true to life as possible.

    You've already heard yaesumofo speak as to the industry use of these things, right? What's your deal here, jtr? Why do you persist on this track? Maybe we can move on, OK? Forget about other uses for the color checker.

    What do you think about how we here want to use it?
    -Jim Sexton, creator of the M6-R, the TigerLight Upgrades, Fixture-ring lamp potting, the SL60, co-designer of the B90 Upgrade, and proponent of the SF A2, the SF M6 X-LOLA, Titanium, the Haiku, and the LunaSol 20

  19. #139
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    Default Re: High CRI and its significance

    Response to js deleted-not worth my while contributing to this thread.
    Last edited by jtr1962; 06-21-2008 at 11:30 AM.

  20. #140

    Default Re: High CRI and its significance

    Want to make this thread easier to read, more pleasant, back OT??? Do as I just did & use the Ignore List function under user profile ... bye bye jtr1962
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  21. #141
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    Default Re: High CRI and its significance

    Quote Originally Posted by precisionworks View Post
    Want to make this thread easier to read, more pleasant, back OT??? Do as I just did & use the Ignore List function under user profile ... bye bye jtr1962
    I know you won't be able to read this due to the ignore function but I'm posting it for the benefit of others. I hope you're happy-I'm now done with this thread and possibly with CPF thanks in part to you. I guess it just bothers some people if you try to challenge a few ideas, or maybe make suggestions to do things better.

    Hope this makes your life better!

  22. #142
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    Default Re: High CRI and its significance

    jtr,

    Don't be this way, please! I don't want you to be done with this thread, and I definitely don't want you to be done with CPF! Please stay. In any discussion, sometimes feathers are ruffled, feelings are hurt, voices get raised. It's par for the course. The important thing is to recover from it.

    I would love to hear your thoughts on how we are planning to use the color checker as a way to illustrate flashlight CRI. We can just drop the other discussion. I'm sorry if I upset you, jtr. Please accept my apology if I did. But, don't go. Or if you must, don't leave CPF! I appreciate your presence here and your contributions.

    And really, you wouldn't be the first to make someones ignore list. I'm sure I've had that distinction myself. It's OK, jtr. It's all good. No worries mate.
    -Jim Sexton, creator of the M6-R, the TigerLight Upgrades, Fixture-ring lamp potting, the SL60, co-designer of the B90 Upgrade, and proponent of the SF A2, the SF M6 X-LOLA, Titanium, the Haiku, and the LunaSol 20

  23. #143
    *Flashaholic* McGizmo's Avatar
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    Default Re: High CRI and its significance

    Well bummer guys!

    Color rendering obviously starts at the source of illumination but as has been discussed and delved into here, when the image is captured by our equipment and not just our eyes, the equipment itself has a way of altering and filtering and remapping the image with its effect on color. At least we didn't get into the issue of perspective itself being altered as well in a captured image if anything but a "normal" focal length lens was used.

    How does the truth in an image compare to the reality of that which it captured? I suppose when it comes to CRI in artifical light sources, we might limit ourselves to the consideration of how better color rendition allows us to capture some "truth" and what we do with it after captivity is perhaps a different topic of discussion?

    The ColorChecker came up in the context of being able to perhaps more easily identify strengths and weaknesses in CRI and more to the point, at what level do excess and deficiencies in a light's spectrum start to obviously alter the appearance of color to a significant or even worse, misleading, level?

    In a somewhat parallel thread regarding the 083 LED's, the question was raised if house lighting based on High CRI LED's would leave guests looking like zombies. Do flashlights make people look like zombies? If yes, why? at what point or condition of spectral basis will a light not make a person look like a zombie? Do the light skin and dark skin color squares on the Color Checker provide a visual clue when illuminated by the light source in question?

    It seems that perhaps we should have an additional thread devoted to the Color Checker itself.
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  24. #144
    Flashaholic* Stillphoto's Avatar
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    Default Re: High CRI and its significance

    I wouldn't imagine the high cri leds causing the zombie coloration. Previous leds with a cool colored output certain would make one's skin more zombielike.
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  25. #145
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    Default Re: High CRI and its significance

    Don,

    Is the idea of square #13 to compare it against square #8 to see if they are the same? If too much red is present, #13 will change color, but #8 won't? Because in your photo above they seem nearly identicle, which would make sense given the light source. Do the directions indicate the way to use the color checker, and might they answer some of the questions we have? Or maybe not?
    -Jim Sexton, creator of the M6-R, the TigerLight Upgrades, Fixture-ring lamp potting, the SL60, co-designer of the B90 Upgrade, and proponent of the SF A2, the SF M6 X-LOLA, Titanium, the Haiku, and the LunaSol 20

  26. #146
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    Default Re: High CRI and its significance

    HI guys.
    Today I went to an industry equipment show called cine gear.
    While there was the usual batch of new cameras and balloons and stuff I was interested to see what was going on in terms of led lighting in the industry.
    Man was I surprised.
    In years past there was the odd manufacture introducing a small light panel. Today there were at least 20 different companies showing High power hi lumen color corrected (some) led lights. There were lots of light panels and quite a few lights which were more like traditional studio lights.
    Emitters used to be only the old style leds with long power Leeds inserted into a circuit board. Now they are using the highest powered emitters from EVERYBODY Nichia, Cree, Seoul, Osram (already heavy into Motion picture lighting)Phillips was there too.
    It turns out that much of this product is driven over from commercial and household lighting (which they say is the holy grail since we me move alone there will be a TOTAL transition over from tungsten and fluorescent lighting to LED lighting. The Home fixtures are being modified to create the basis for motion picture instruments.
    CRI for the most part is in the 80's. There are filter kits included with just about all of the new systems which are used to alter the color temperature and "look" of the light.
    Some are tunable from cold to warm and anywhere in between (very cool) there was one color kinetics instrument filled with Cree emitters that was completly tunable the amber emitters were clearly the choice to "warm" up the light NOT RED or any other color.

    I really wish I had my camera with me today but it was just not possible with it being over 100 at the OUTDOOR show (except the tent with all of the LED stuff). The CRI number seemed pretty important to some but not others. EVERY one of the companies I talked with said there product was superior. I was quite amazed at the variety. Some were very nice. I was very impressed with the Phillips/color kinetics stuff which was using CREE emitters. I saw another light which was using a (special) OSRAM emitter. I have a feeling that many of these guys are using off the shelf stuff. NONE had any idea about the nichia) 083 HI CRI Most were EXTREEMELY impressed with the sundrop for what is was and clearly were impressed with the quality of the light. I have a feeling that some of these companies will be looking for these emitters and if nothing else they will be looking at the Nichia line more closely. Interesting what happens when you show guys who know and are interested in light something they have not seen with a color temperature and CRI # that they are very interested in ...
    BTW I had so many of these guys comment about the Lunasol 27 I had around my neck. They all assumed that it was one of those crappy ligvhts with 36 emitters...When they say what it was and how it worked they were BLOWN AWAY!!

    More if I can remember it later.
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  27. #147
    *Flashaholic* McGizmo's Avatar
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    Default Re: High CRI and its significance

    Quote Originally Posted by js View Post
    Don,

    Is the idea of square #13 to compare it against square #8 to see if they are the same? If too much red is present, #13 will change color, but #8 won't? Because in your photo above they seem nearly identicle, which would make sense given the light source. Do the directions indicate the way to use the color checker, and might they answer some of the questions we have? Or maybe not?
    js,
    To my 56 year old eyes #8 just looks like a flat blue, lighter in tone and less "vibrant" perhaps than #13. This is under a noon sun and reasonably represented in the photo above. Your question got me suspicious and I dug out a Gladius incan and hit the color checker and under its illumination, I could see where the name purplish blue might be appropriate.

    The instructions also suggest that #6 and #11 can reverse if there is a problem with yellows and blues.

    It also states that if the grays remain neutral but the other patches change that you have either a blue, yellow or red problem.

    It does not get into the nature of what these problems might be. It sugests for more about color control that you visit www.xrite.com or www.i1color.com .

    *****

    Yaesumofo,
    Cool!!
    Build Prices .... some mods and builds (not 4 sale) "Nature can be cruel- but we don't have to be."~ Temple Grandin

  28. #148
    Flashaholic* Stillphoto's Avatar
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    Default Re: High CRI and its significance

    Yaesu...Wondered if I was going to bump into you there. I was there yesterday. I too was blown away by the number of companies pushing led lighting now.

    I like that Philips decided to jump into the movie light arena, I picked up their solid state lighting manifesto and am currently drooling over some of it. They were also considerably more knowledgeable and easier to talk to than some of the others.

    Ledz definitely uses off the shelf optics for their little 3 led minipar lights...Looks like they offer the spot, med, and flood optics I've seen elsewhere.

    Kino's stuff was sorta interesting...viewable here http://kinoflo.com/Lighting%20Fixtur...elvinTile.html


    I was also suprised to see how many were mixing both warm white and cool white leds, and had controls to dial in just how warm or cool you desire.

    Did you catch that one guy outside that had those lights with 6 or so of the 6 die leds? They were bright but they looked pretty blue.
    Last edited by Stillphoto; 06-21-2008 at 09:56 PM.
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  29. #149
    Flashaholic* yaesumofo's Avatar
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    Default Re: High CRI and its significance

    I did and they claimed a custom or semi custom Osram part.
    IMHO the Phillips/color kinetics guys were absolutely the smartest. They are focused on lighting homes, business, hotels, kitchens, and so forth. As a result the MP industry benefits from the very advanced technology. I really liked their tunable and very bright lights. They have a complete 3 light package in cases with EVERYTHING for under 6K. Not bad for the most advanced lighting around..
    I figure that next year some of the stragglers will be weeded out. The Higher CRI lights will be in and companies like Philips and kinoFlo will become the market leaders in the industry...We will see.
    Did you notice that they all claimed best output and color rendering? pretty funny. I think it would be pretty cool so send out a few of each to a lab for independent testing for CRI power spectrum and so fourth to see what is what...
    Yaesumofo

    Quote Originally Posted by Still photo View Post
    Did you catch that one guy outside that had those lights with 6 or so of the 6 die leds? They were bright but they looked pretty blue.
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  30. #150
    Flashaholic* adamlau's Avatar
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    Los Angeles
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    Default Re: High CRI and its significance

    The i1Display 2 colorimeter has an ambient light checking feature to measure CCT (K) and illuminance (lx). Ambient light in front of the monitor at seating eye level registered 5000 K and 55 lx (recommended target values for color judgement viewing on monitors). I now see the forums displayed in their intended color schemes . I thought I had favored cooler temperatures in the past, only to now come to the realization that I prefer warmer, calibrated profiles (). Placed an order for the ColorChecker to compare againt calibrated monitors. That said, my next paycheck will be going towards a nice S-PVA panel (Samsung XL20, or equivalent). I just might spring for the ColorMunki as well. I entered this discussion to learn about CRI and will come out of it with at least a colorimeter, a color chart and hopefully a high end monitor . Want to see the effects of a calibrated monitor? If you have any of the following systems, you can download and give these standardized (6500 K, gamma 2.2, 120 (LCD), or 90 (laptop) luminescence) ICC profiles a try. Although specific to the conditions of my systems (test your system for ICC v4 compliance), they can be useful in giving you a general idea of how a calibrated monitor looks and feels:

    iMac7,1 (20"): X-RiteiMac71LUTv4.icc | X-RiteiMac71Matrixv4.icc
    ThinkPad T42 (15"): X-RiteT42LUTv4.icc | X-RiteT42Matrixv4.icc
    ThinkPad T60 (15.4"): X-RiteT60LUTv4.icc | X-RiteT60Matrixv4.icc
    Samsung 906cw (19"): X-Rite906cwLUTv4.icc | X-Rite906cwMatrixv4.icc | X-Rite906cwMatrixv2.icc
    Gateway M-1617 (15.4"): X-RiteM1617Matrixv4.icc | X-RiteM1617Matrixv2.icc
    ViewSonic VP2130b (21"): X-RiteVP2130bLUTv4.icc - Coming Soon
    ViewSonic P225f (21"): X-RiteP225fLUTv4.icc
    Dell 2407WFP (24"): X-Rite2407WFPLUTv4.icc - Coming Soon
    Last edited by adamlau; 06-24-2008 at 01:07 AM.
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