CRI and TLCI explained by a scientist - Delimex.be
HTML-код
- Опубликовано: 29 окт 2024
- CRI and TLCI explained and demystified by a scientist, along with some background info.
We tried to provide you with a comprehensive background on CRI, TLCI and how light and colours work, but in short form and geared towards videographers and cinematographers.
For more info, have a look at www.delimex.be or on our social media.
CRI and TLCI concepts are very nicely explained and demonstrated. There can't be more simplified way to explain than this. Thank you.
Thanks!
I am shocked at there being so many dislikes. I just bought the nanlite forza 60 and came to learn more about the CRI/TLCI. This is a very well made and educational video. Thank you sir!
Thank you, Matthew. I suppose people were expecting something else? Eather way, I hope you enjoyed it and I'm glad it managed to be educational to you.
I think it's because he called people with aphakia "freaks of nature". Kinda out of place in such type of content honestly.
That last little nugget explaining color temperature MADE this video for me...thank you!
Glad to help
Absolute Gold. Ive been looking for a video like this for years.
Thanks Joshua, Please consider subscribing - more videos to come.
Super stuff! I was looking for exactly this. Thanks for making this video, very helpful...
Great video, very informative and to the point. Nice mascot too.
Thanks!
Great video, exactly what i was looking for!
Thanks! We aim to please :-)
Very helpful to understand the physics of light. Much appreciated. Explained in a fashion I understand. 10/10
Thanks!
I know it is kinda off topic but does anybody know of a good website to watch newly released series online ?
@Nathanael Marcel Flixportal :P
@Jesse Kenzo Thank you, I went there and it seems like a nice service :) I really appreciate it !!
@Nathanael Marcel You are welcome :D
This is a great explainer! I am surprised you don’t have more subscribers. I am one now.
Thanks, man. And thanks for subscribing!
Great Video in every respect, informative, educational, production quality, ...and just a little bit of 'theater' to make it entertaining. I understood the topic because you understood it .. that is refreshing on YT and an extremely desirable quality in any teacher (Feynman lectures come to mind). (As a non videographer) I wish there were more tutorials like this on Stills photography crossover topics eg dynamic range and exposing to right or left, DoF/ FL considerations at macro vs telephoto range, focus breathing, etc (the list goes on). Well done! David
Thanks David
Very Informative Video Buddy , and I also have a question , So what should be the CRI/TLCI of the Only blue or green color light which have very narrow beam of wavelength in color spectrum, as they have not wide range of color wavelengths in it, please clear my doubt sir.
There should be no CRI, nor TLCI. The thing is that those measurements are intended to make some kind of appreciation for a very wide color range, white that is. For a single colorn CRI or TLCI would have simply no meaning. If you'd do it anyway, most factors would be near zero and perhaps for the color it is, it could be high if the colour is just coinciding with one of the colors checked in the method (may that be CRI, CRI-E or TLCI). ANd that would be hit and miss solely because of the colour inspected. Also - you have to compare it to an ideal choice with the same color temperature, but obviously a very narrow color doesn't have a color temperature, so that would not even work. So, in short - this method wouldn't work for a specific color, as it isn't meant for that, the mathematics don't work and any result would therefor be meaningless.
Ohhh Thank you so much sir 😊🙏🏻 Keep posting stuff.
This is so good an in depth! Thank you!!
Thank you
Best Video. Thanks
Excellent presentation.
Thanks!
it was such a fantastic video ..thanks man
Thanks, I hope it was helpful for you.
Great Explanation
Which color temperature comes the closest to the Sun's white when there's no shadow or color cast? Is it 5500K or 5600K or maybe some other value?
That is a good question - and I may have been more clear on that in the video. The thing is that is colour temperature of the sun changes during the day. When the sun is at its highest (around noon on the longest day of the year), the colour temperature is very high - way over 6000 Kelvin. When the sun is very low (close to sunrise or sunset), the colour temperature is very low - around 3000 K. So the 5600 K setting that you find on cameras is a approximate value during the day - a good setting for full sun or light clouds and far enough away from sunset or sunrise, but the actual colour temperature is very dependent on the time of day. I hope this answers your question, ifochancroft.
@@DELIMEX Thank you! I should have probably asked my question better: Which color temperature is the closest to pure white?
@@ifohancroft No, the question was clear. The actual colour temperture of the sun is dependant on the time of day. So there is not just one colour temperature that is closst, I'm afraid. But in summer at noon in a clear sky, it is way higher than 5600, that's for sure. The only way of knowing is measuring the colour temperature at the time of shooting (and you can measure it with most cameras). Full sun, noon in summer might easily be around 7000 K and a few hours earlier it might be just 5200K.
@@DELIMEX Thank you! I was hoping there is a particular color temperature where the intensity of the different wavelengths is exceptionally even.
@@ifohancroft Yes, unfortunately no such luck :-).
Excellent! Thank you.
Thanks!
Great explanation, however... this girl... Are we back to 1990?
Thank you, we hope the information is useful. We don't really see the examples as a throwback to the 90's ourselves, but if you do, a little nostalgia is a good thing though? :-)
@@DELIMEX i think i know what he ment with "1990" there where TV programs send at night (22h, 10pm) usually on sport channels which show some sort of (very) soft core erotic clips. To be honest i clicked on the video since i wanted to know why the heck are these fetish gloves needed when handling CRI :D :D :D, best regards
@@hyperhektor7733 One can never be too careful with a worldwide pandemic going around these days :-). It's our trademark branding for a while now and we know some people like it, some will not. We'd rather have it that way than leaving people without any reaction. Videos with a scientific inclination such as this can use some sprucing up - we're not ready to make boring videos yet :-). More to come, I'd say!
@@DELIMEX i didn't looked up the other videos, makes sense for company to target their main audience this way. I am not a PC nor a Pandemicfan so cant comment on that topic ;D (otherwise my comment will be censored).
@@hyperhektor7733 Oh no, I wasn't insunating you were. I hope you enjoyed the video anyway, that would be enough for u :-).
Best explanation out there.
Thanls, Keith
Fantastic explanation - thank you
Thanks Paul! Please consider subscribing - there are quite a few more videos to come.
@@DELIMEX thank you - yes subscribed. Cheers.
Why would it be hard to make all LEDs with high CRIs? is it a manufacturing issue? What about the actual component changes?
Just designing a light that would score high on the CRI or TLCI scale is one thing, but you'd need a good output as a manufacturer to deliver a performant light. So changing out the ingredients just to hit a high CRI/TLCI will not be enough as that might effect efficiency negatively. Or price might also be affected. So all in all, it is more the trade-off than a manufacturing issue.
@@DELIMEX yes. It's just interesting that my 1200 watt LED light which was made for film costs 3000 but a 1200 watt light that is used to illuminate a sports field is only 700 dollars with a cri of 75
@@davida5296 Yes, that would be one of the reasons. Also, any product specifically for the cinematography sector will be priced high because it is a relatively low production volume. So you're always paying a high premium for the enclosure, operating parts etc. If these manufacturers sold the volumes that mobile phone manufacturers do, the prices would be a lot lower.
How TLCI is different from CRI? Please make video on that.
I think you just saw a video that explains how it is different. Or is it not clear in some way?
That "freak of nature" comment didn't ring well for me... :/ There are actual people born without a lens who can see UV down to 310nm.
NICE ONE!
Helpful video
Thanks!
TLCI does not apply to single-chip cameras as it was designed for prism cameras. CRI is an IES metric that is not based on the camera response. If you would like to see a method to balance LED lights to the needs of the camera based on the cameras chroma signal you may want to see an interview done for Digital Cinema Society about the HS Scope. vimeo.com/405567769
When commercially buying lights (LED or others) you'll be most likely limited to information about CRI and TLCI. TLCI still gives you better accuracy than CRI for lights for camera usage.
Yes, unfortunately, those metrics are used as a marketing tool yet their relevance is often not understood in relation to the camera actual response. TLCI uses a virtual 3 prism camera model and uses averaging. In regards to a single chip camera, even the creator of TLCI has acknowledged it is not designed for signal chip cameras. I have bought many LED fixtures for on-camera use and that is why I used the camera's electronic chroma response to evaluate and calibrate LEDs for the camera. As you say manufactures give limited information when they use specifications such as CRI and TLCI for single-chip cameras.
@@lightingvideotv Well,You can understand that any method to measure the quality of the output of any light can not be influenced by the camera used. Than you would essentially be judging your camera as well (scientifically speaking). So any method using the camera output shouldn't be used by manufacturers, that goes without saying. Now, I do agree no method is ideal, but you should keep in mind what any rating is meant for. The only and best way to judge the quality of light would be to compare the spectrum of a light to the ideal situation. Which would be no problem for me or any other interested or educated person. However, these ratings are meant to give 'an idea' about the quality with a simple number (up to 100), so people that need a light - and are not necessarily so technically inclined - can judge (easily and fast) if a light is any good. Some ratings are better than others (TLCI is more precise than CRI for instance), but they all cut corners, but they still give valuable info to have any idea of the quality of a light without comparing spectra that some people don't really understand. For example : I've met people in the past that do believe that natural light (e.g. the sun) is a combination of just 3 colors instead of a continuous spectrum. And these people buy lights just the same.
@@HATONA if you are looking for Lighting metrics that take the physical camera out of the equation then I would note SSI and TM-30-18 are being adopted over CRI and TLCI by some cinema associations.
@@lightingvideotv I agree there are other standards, but then again - it is a question for buyers which info is readily available. Mostly that's just CRI and TLCI. CRI is very crippled due to little reference points, TLCI is better. If a light scores high on the TLCI range it stands to reason it will likely score high in other measuring units. Again, there's no way better than precisely comparing wavelength response curves, but this is not a technique that everyone is capable of. SO most people are forced to make a decision based on CRI and TLCI figures (mostly just provided by the manufacturers to make matters worse, and I can tell you that we have a hard time reproducing them with some brands).