Help me understand the draw of RGB lights?
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CharlesPapert
Director of Photography
That's a pretty substantial achievement--I've been very happy to avoid the various flavors of CTO/CTB with bicolor instruments in recent years and while that is an everyday occurrence while party gels were more specialized, the process of having to pore through swatch books and test multiple versions to find the right shade (or make do with whatever scraps you had in your party gel grab bag) was always a PITA. Now we can watch on the monitor and dial in the desired hue and saturation on the fly, which is far more precise and convenient. Also, deep colors always required high wattage instruments due to the lower transmission values. Arguably, not all instruments can replicate all gel colors but like all things LED related, they are continually evolving.
If one never or very rarely uses any flavor of party gel to begin with, then RGB units don't represent much of a revelation.
If one never or very rarely uses any flavor of party gel to begin with, then RGB units don't represent much of a revelation.
CharlesPapert
Director of Photography
Sure, it's quicker, but party gel costs money too, especially if you are talking about multiple units. At $120 a roll, having a few options adds up quickly.
And no, it is no longer acceptable to breathe on set. Strictly forbidden! We talk about this often actually. Reloading film was an opportunity to discuss notes on the shot--that time is gone and we do most of it over walkies now in stolen moments. Sad.
And no, it is no longer acceptable to breathe on set. Strictly forbidden! We talk about this often actually. Reloading film was an opportunity to discuss notes on the shot--that time is gone and we do most of it over walkies now in stolen moments. Sad.
Saw these recently, might try as an occasional colored background or something. Cheap enough to play with, at least.
https://www.bhphotovideo.com/c/prod...O4JKk7Yn2Ce1CWxZvl_Fth5AHBoCI6kQAvD_BwE&smp=y
https://www.bhphotovideo.com/c/prod...O4JKk7Yn2Ce1CWxZvl_Fth5AHBoCI6kQAvD_BwE&smp=y
abreu-canedo
Well-known member
It's not just a time is money thing. The less time it takes to find the perfect color, the more likely we are to find it. It also leaves more time for doing other things to perfect your image...or it gets you that extra shot you suggested to the director. It actually has helped me to execute better images in many instances.
I use RGB mostly for night time shots, where I can simulate commercial sign lighting, or creative moonlight looks. I also use it a lot in studio shoots. I barely use it on daytime shoots, but that's just because of the jobs I'm getting. I'm trying to get directors to experiment more with peachy and lavender sunset lighting, for example.
But, for example, natural interiors it's mostly kelvin scale with +/- green. In fact, for working in kelvin scale, there's are many who prefer non-RGB lights. While I trust them and follow suit, I haven't done the tests to corroborate in any technical way. So not everything needs to be RBG, but I always try to have some RGB units.
I wouldn't invest in that light stick, if I were you. It's not bright enough to really be sure useful out of frame, and not a form factor that can be easily used as a practical. Perhaps a 2' RGB tube from the likes of Quasar Science or Digital Sputnik, for example. Can be used as practical more easily, but maybe not much brighter?
I use RGB mostly for night time shots, where I can simulate commercial sign lighting, or creative moonlight looks. I also use it a lot in studio shoots. I barely use it on daytime shoots, but that's just because of the jobs I'm getting. I'm trying to get directors to experiment more with peachy and lavender sunset lighting, for example.
But, for example, natural interiors it's mostly kelvin scale with +/- green. In fact, for working in kelvin scale, there's are many who prefer non-RGB lights. While I trust them and follow suit, I haven't done the tests to corroborate in any technical way. So not everything needs to be RBG, but I always try to have some RGB units.
I wouldn't invest in that light stick, if I were you. It's not bright enough to really be sure useful out of frame, and not a form factor that can be easily used as a practical. Perhaps a 2' RGB tube from the likes of Quasar Science or Digital Sputnik, for example. Can be used as practical more easily, but maybe not much brighter?
cpreston
Veteran
The newest lights are more like RGBWW with the primary LED's being a tungsten and day light mix. The colored lights are used for effects and corrections. I don't know the appeal other than I find that dialing in +/- green to be kind of a pain with gels. It is just much simpler to dial everything in on the control panel of the light when trying to match environments.
paulears
Veteran
As a theatre lighting person, you've missed one vital part. "party' gel - is a term I've never heard before. We use gel. No idea where the 'party' bit comes from. Rosco and Lee are the two big firms who make hundreds of different colours. Vital stuff for theatre. BUT - the cost of the gel, the cost of the time to cut it and fit it, and the lifespan before not burns out and lightens is considerable. We could have a show come in and spend three hours fitting it, with a considerable cost to the incoming show. The designers spend ages pre-choosing colours only to find they are not quite right.
The other very big flaw with gel is that they are subtractive. You shoine 1000W of white light through them, remove the red and remove the green and what comes out is blue. 2/3rds of the power wasted in conversion to heat. If you want a very deep blue - the very popular Lee or Rosco 181 Congo Blue lets through just 1% of the light, and has a very short lifespan as the remaining 99% is dissipated as heat! 3 hours burns a brighter circle in the gel!
Washing an entire stage with deep blue is practically impossible with gel.
Move to RGB and things suddenly get exciting. You might have 150W worth of Blue. Absolutely no red or green component. You can make the stages really bright with blue for the very first time and drive the video people nuts because their cameras cannot process it properly. They have trouble with exposure and focus. Oh dear. Of course you have the red and green colours too.
By additive mixing, you can get a vast range of shades, plus the obvious secondary colours, magenta, cyan and yellow. R+G+B = White, except it doesn't. It produces a kind of bright murky white that again, video folk hate. To be honest, we hate it too because it simply will not match with real white from tungsten sources. We are NOT talking about colour temperature. In theatre it's quite common to have equipment from years ago still working - with non-halogen lamps at 3000K, or even 2800K. Our RGB mixed white is not remotely the same, and being made up of lots of spikes, doesn't really even have a colour temperature. Lots of our lights have a white LED, but while being better than the mixed white from RGB LEDs, it's still not really white, but quite blue - 5000K upwards? My latest LEDs are RGBWAUV = Amber and UV being added. LED blue contains quite a bit of UV light, which means any fabrics or paint that fluoresce, will start to look brighter, even odder to a camera. If you want things to fluoresce properly, there is too much blue visible light - the UV light is much better - with less visible light. Real discharge UV lights using woods glass filters are still the best, but the UV LEDs do a pretty reasonable job. The amber, by the way, is there because additive mixing produces pretty poor shades of gold and amber, so the amber colour gives more range in the orange area. In theatre we aren't really in treated in colour matching with white light, because we tend to tint everything if we get the chance. Instead of a fixture with no colour frame for white, we might have a very light straw colour in it. OW - open white is used, but often just for visibility, and it's common for us to run them at anything other than full - which turns them yellowish anyway. I'm old enough to remember broadcast TV running everything at .7 on the fader. So all the 3000/3200 labels going out of the window. If you white balanced cameras to .7 on the fader, you could go up to full, or down to half with a smallish change of the colour and get away with it. White balancing to full, meant adjustments could only be downwards, so if you wanted to lift an area, you had to dim the rest, which messed up the racks people badly.
Now we have TV LEDS with two colours which gives more control again. My theatre 'white' is not remotely white to cameras, but while I can now buy bright Fresnels (well, the modern version of what they call Fresnel) in white, they fall down when you stick gel in them. Lee and Rosco now produce gel to match their other range designed ONLY for LED white. If you hold the LED and the Tungsten version of the same colour up to sunlight the colours are amazingly different - yet when on the fixture they produce the same colour.
Colour theory is fascinating stuff and I'm amazed nobody ever seem to use it on cameras. As it's subtractive, you can produce some amazing effects by sticking g them on cameras like they did in the movie industry with proper glass colour. However, modern plastics are pretty good optically and as they're out of focus on the lens hood, they can work pretty well. Turning day to night, or bizarre colour changes - a small lensed camera and a Lee swatch sample book produce hours of fun.
The other very big flaw with gel is that they are subtractive. You shoine 1000W of white light through them, remove the red and remove the green and what comes out is blue. 2/3rds of the power wasted in conversion to heat. If you want a very deep blue - the very popular Lee or Rosco 181 Congo Blue lets through just 1% of the light, and has a very short lifespan as the remaining 99% is dissipated as heat! 3 hours burns a brighter circle in the gel!
Washing an entire stage with deep blue is practically impossible with gel.
Move to RGB and things suddenly get exciting. You might have 150W worth of Blue. Absolutely no red or green component. You can make the stages really bright with blue for the very first time and drive the video people nuts because their cameras cannot process it properly. They have trouble with exposure and focus. Oh dear. Of course you have the red and green colours too.
By additive mixing, you can get a vast range of shades, plus the obvious secondary colours, magenta, cyan and yellow. R+G+B = White, except it doesn't. It produces a kind of bright murky white that again, video folk hate. To be honest, we hate it too because it simply will not match with real white from tungsten sources. We are NOT talking about colour temperature. In theatre it's quite common to have equipment from years ago still working - with non-halogen lamps at 3000K, or even 2800K. Our RGB mixed white is not remotely the same, and being made up of lots of spikes, doesn't really even have a colour temperature. Lots of our lights have a white LED, but while being better than the mixed white from RGB LEDs, it's still not really white, but quite blue - 5000K upwards? My latest LEDs are RGBWAUV = Amber and UV being added. LED blue contains quite a bit of UV light, which means any fabrics or paint that fluoresce, will start to look brighter, even odder to a camera. If you want things to fluoresce properly, there is too much blue visible light - the UV light is much better - with less visible light. Real discharge UV lights using woods glass filters are still the best, but the UV LEDs do a pretty reasonable job. The amber, by the way, is there because additive mixing produces pretty poor shades of gold and amber, so the amber colour gives more range in the orange area. In theatre we aren't really in treated in colour matching with white light, because we tend to tint everything if we get the chance. Instead of a fixture with no colour frame for white, we might have a very light straw colour in it. OW - open white is used, but often just for visibility, and it's common for us to run them at anything other than full - which turns them yellowish anyway. I'm old enough to remember broadcast TV running everything at .7 on the fader. So all the 3000/3200 labels going out of the window. If you white balanced cameras to .7 on the fader, you could go up to full, or down to half with a smallish change of the colour and get away with it. White balancing to full, meant adjustments could only be downwards, so if you wanted to lift an area, you had to dim the rest, which messed up the racks people badly.
Now we have TV LEDS with two colours which gives more control again. My theatre 'white' is not remotely white to cameras, but while I can now buy bright Fresnels (well, the modern version of what they call Fresnel) in white, they fall down when you stick gel in them. Lee and Rosco now produce gel to match their other range designed ONLY for LED white. If you hold the LED and the Tungsten version of the same colour up to sunlight the colours are amazingly different - yet when on the fixture they produce the same colour.
Colour theory is fascinating stuff and I'm amazed nobody ever seem to use it on cameras. As it's subtractive, you can produce some amazing effects by sticking g them on cameras like they did in the movie industry with proper glass colour. However, modern plastics are pretty good optically and as they're out of focus on the lens hood, they can work pretty well. Turning day to night, or bizarre colour changes - a small lensed camera and a Lee swatch sample book produce hours of fun.
nyvz
Veteran
Yes one nice "utilitarian" use is dialing in exactly matched tints for various practical lights and even movie lights. With the prevalence of limited-spectrum sources it is common to have even >90cri HMIs not match LEDs and have LEDs not match other LEDs and to have that difference render differently depending on CFA design on the digital camera you're using. Now you can dial out differences (at least in white point) so it looks like your sources match on monitor. And yes also party gels and essentially on set interactive lighting-grading on the fly which might allow you to acheive certain effects on set that would've in the past only been possible in post grading with power windows or rotoscoping. Subtle effects some of which technically might have been possible with gels but could not be tweaked on the fly quickly enough or precisely enough with gels to be worth trying.
+1 on this. While I currently don't need deep colors for most of my work, being able to do so with very low wattage instruments is a revelation. And I've been happy to loose that party gel grab bag / roll in my kit.
Run&Gun
Veteran
Yep. I've pretty much always referred to any gel that wasn't color correction(including colors like straw used for subtle natural lighting effects) or cosmetic(like Gam warm hint, tan hint, etc.)as "party gel". I don't remember if it was Lee or Rosco that used to sale a pack of theatrical(non-color correction) gels called the party pack.
combatentropy
Veteran
When your life is one big party, there's little need to distinguish it, then.
paulears
Veteran
I guess just one of the terms that hasn't travelled the Atlantic. Theatre people do use CT, for very subtle tints - especially the blues. All our colours fall into either warm/cool or special effects.
Clearly the theatrical need for changes of colour is to do with mood, and how colour impacts on the audience. They also suffer from colour forgetfulness. A scene lit with a strong blue light becomes 'white' after just a few minutes - the eye/brain doing an auto white balance. Cameras respond so differently. Stanley McCandless, who contributed much to the art of stage lighting also introduced a novel concept - two lights each from 45 degrees off centre and looking down to the subject at 45 degrees create good sculpting for everybody in the audience - totally different to video key and fill - and worse for the video people trying to shoot a theatre show like a straight play, his 'trick' was to colour them differently - warm (pinky) on one side and cool (bluish) on the other. String colours were strictly for special effect - not realism. Hence the huge range of colours available. Perhaps this background is handy when video folk go into theatres and complain about the huge colour shifts and lack of anything you could WB to. Lighting to the theatre goer is like a zoom lens is to a camera person - a way to draw the eye to what you want them to see. Theatres don't have zoom capability but they do have intensity and colour shifts which can do very similar things. Worth pointing out that ignoring the show Wicked, one colour that rarely gets used is green - especially primary green. It makes white skin go green, but it makes darker skin types look horrible. Anyone with really dark skin pigmentation looks grey and ill, it's very unflattering and usually avoided.
If you want to do a bit more reading on theatre weird colour experiments - Goggle Samoiloff Effect, and for once, it beats Wiki! Can be amazing though.
Clearly the theatrical need for changes of colour is to do with mood, and how colour impacts on the audience. They also suffer from colour forgetfulness. A scene lit with a strong blue light becomes 'white' after just a few minutes - the eye/brain doing an auto white balance. Cameras respond so differently. Stanley McCandless, who contributed much to the art of stage lighting also introduced a novel concept - two lights each from 45 degrees off centre and looking down to the subject at 45 degrees create good sculpting for everybody in the audience - totally different to video key and fill - and worse for the video people trying to shoot a theatre show like a straight play, his 'trick' was to colour them differently - warm (pinky) on one side and cool (bluish) on the other. String colours were strictly for special effect - not realism. Hence the huge range of colours available. Perhaps this background is handy when video folk go into theatres and complain about the huge colour shifts and lack of anything you could WB to. Lighting to the theatre goer is like a zoom lens is to a camera person - a way to draw the eye to what you want them to see. Theatres don't have zoom capability but they do have intensity and colour shifts which can do very similar things. Worth pointing out that ignoring the show Wicked, one colour that rarely gets used is green - especially primary green. It makes white skin go green, but it makes darker skin types look horrible. Anyone with really dark skin pigmentation looks grey and ill, it's very unflattering and usually avoided.
If you want to do a bit more reading on theatre weird colour experiments - Goggle Samoiloff Effect, and for once, it beats Wiki! Can be amazing though.
CharlesPapert
Director of Photography
When we were putting together the lighting plan for the Key & Peele sketch "Aerobics Meltdown", we were able to leverage RGB units for the set which was still on the exotic side in 2014. As a result, the director and I could sit at the monitor and find the desired colors for the "tubes" (actually RGB ribbon) and cyc wash, which ended up quite different than the period reference material the sketch was based on. If we had relied on gel, we would have been locked into a specific color scheme.
I used to somewhat dread the gel-picking sessions when we had a nightclub, party or similar set coming up--rummaging through the swatch books and picking out a set of colors and hoping we'd love them on the day. I bought my first RGB units back in 2009 or so, the Zylight Z90 and IS3 (which I still have but am about to sell--anyone want?!) and it was a real revelation to be able to dial in colors.
I used to somewhat dread the gel-picking sessions when we had a nightclub, party or similar set coming up--rummaging through the swatch books and picking out a set of colors and hoping we'd love them on the day. I bought my first RGB units back in 2009 or so, the Zylight Z90 and IS3 (which I still have but am about to sell--anyone want?!) and it was a real revelation to be able to dial in colors.
fboonzaier
Well-known member
I still remember the days of the AC asking the DOP whether he "wants a hair in the gate"....those moments served any project far better...A frequent complaint I read about the Varicam LT is that it takes some 20 seconds to turn on or to reboot! I have know idea how they would have survived changing out film mags...advances often do not improve results though...at least not in narrative (sorry off topic!)
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Run&Gun
Veteran
Off the original topic, but on this one, one of my friends uses his audio guy to buy him time. "Waiting on audio..."
morgan_moore
Major Contributor
I think they are good for branded content and hitting 'brand colours'
Just shot this https://www.facebook.com/Yazoo/videos/2248496388497834
Chocolate, we also did straberry and banana.
Art provided backdrops.
I felt the strab backdrop too red and the banana not yellow enough.
WIth RGB onto a perspex backdrop sucha colour critical job could have been dialled.
--
Last week I did a pop vid of a 'slushy' tune - I tried to get some skypanels (and a programmer) as it would have been cool for the light to slowly move through the verses, and hit a different key in the Chorii - here you have both RGB and a requirement to program it.
We filmed an upeat track at the same location. For that I went my usual route of having a grip wildly wave a board in front of a hot light to create a strobe effect
again here controllable light would be good.
Interesting times.
--
Of course there is a danger of them becoming 'the norm' without a suitable rise in fees - gotta watch that!
S
Just shot this https://www.facebook.com/Yazoo/videos/2248496388497834
Chocolate, we also did straberry and banana.
Art provided backdrops.
I felt the strab backdrop too red and the banana not yellow enough.
WIth RGB onto a perspex backdrop sucha colour critical job could have been dialled.
--
Last week I did a pop vid of a 'slushy' tune - I tried to get some skypanels (and a programmer) as it would have been cool for the light to slowly move through the verses, and hit a different key in the Chorii - here you have both RGB and a requirement to program it.
We filmed an upeat track at the same location. For that I went my usual route of having a grip wildly wave a board in front of a hot light to create a strobe effect
again here controllable light would be good.
Interesting times.
--
Of course there is a danger of them becoming 'the norm' without a suitable rise in fees - gotta watch that!
S