Talked to a director yesterday who wants me to shoot a music video for him on my EX1. His idea is to key the talent with an orange light to get a warmer skin tone than the background and make the background even colder in post, either green or blue. The idea is that with orange light on the faces it would be easier to make the rest cold without affecting skin tones. But doesn't the EX1 have a problem with the blue channel similar to the RED ONE? I think throwing orange light on the talent will only make this worse and will produce noise? In any case there are a couple of ways of going about that. You can either set the camera to day light and film with tungsten or set the camera to tungsten and CTO the tungsten lights. If the director really insists in doing that which way is better? Or should I just try to persuade him to drop the idea all together because of the blue channel problem? Thanks.

you could put a orange filter on the lens and show him some footage to see if thats what he
wants

You're making a basic assumption that the noise is undesirable. That may not be the case in a music video.

You may also want a Picture Profile tailored to the desired look.

You may need to do a test shoot if there's a budget for it.

Don't use just any orange gel, use a Roscoe Cinegel 3/4 CTO gel (http://www.rosco.com/us/filters/cinegel.asp). They come in full, 3/4, 1/2, 1/4 and 1/8 versions. A 3/4 CTO provides a shift of color temp from 5500˚K to 3400˚K. These gels have very specific transmission characteristics so that neutralizing their color in post will be easier and more accurate.

You can also gel your lights on the subject, use cooler lights on the background, then set your white balance (using an appropriate card) to the warmer lights. This will cool of the background nicely and require much less time in post.

Another technique would be to use Kino-Flo 3200˚K lamps on the subject and Kino 5500˚K lamps on the background. This eliminates the use of gels and will not diminish light output.

ALL video cameras have a "problem with the blue channel", not just the EXs. No matter which camera he uses he will have the same issue.
The best way to achieve what he wants is to light the talent with tungsten, the background with daylight and add a CTB filter in front of the camera with the camera balanced for daylight.
You might find that makes the background bluer than desired. Adding fractional CTB gells to the talent's lighting and reducing the CTB filter on the camera to adjust to taste.

First and foremost, are you shooting in a controlled environment (i.e. lighting from scratch, like a studio or night interior/exterior) or will you be shooting in actual daylight? If the latter, you will indeed need to "cheat" the lighting on the actor as you won't be able to control the background. Shooting with the camera on 3200 and using 3200 lighting on the actor will give you the separation you need to pull the rest apart with color correction (a lot of high-end work is shot normally and the actors isolated and backgrounds shifted purely in post, but this is laborious). As indicated above, it may be "too much" to use full CTO on top of this (which would give them effect of double CTB on the background, but possibly create noise as you were thinking), but you can use partial CTO, perhaps 1/2 to limit the overdriving in the red channel. Bob had a good concept going here, although I think you might have missed one aspect--camera balanced for daylight plus an 80A filter (tungsten to daylight, effectively the CTB filter you were describing) but you need to light the actor with full CTO, not straight tungsten. If this effect is too much, I would back off the levels of CTO rather than add CTB to the lighting (you start to get some weird shifts doing that) and adjust the white balance to taste. If you were going for a green background instead of blue, you would be working with minus green gel on the talent.

Be aware though that it is tough to overpower daylight, both in terms of pure output and coverage--you'll need a lot of light and from multiple directions to avoid bleed. If the subject is relatively static, you can essentially box them out with flags to knock down the ambience and then rebuild it with lights, but this is a big process. I did a series of interviews years ago where I did this, and lit the actors with various colors and then white-balanced them out to drive the backgrounds into interesting tones. It works very nicely but it takes a while, and those were people just sitting on chairs.

If you are lighting from scratch it's much easier to just light the backgrounds with the appropriate color tones you are looking for. You need to have plenty of separation between the talent and background to avoid contamination once again, or a lot of flagging.

Have you considered shooting the foreground element as a blue/greenscreen and doing a practical on the background and then just handling them as plates?

OK, I managed to confuse everything with that last post (I left it intact in case those who are subscribed to this thread read it via email).

In the situation I described at the end of paragraph 1, let me rephrase while I correct. I'll simplify by using orange and blue as units, referring to the shift between 3200 and 5600.

Shooting in a day exterior, start by balancing the camera to tungsten (not daylight as I said in the previous post). This will shift everything to blue.

Now light the talent with 3200 units (tungsten/kino etc). He will appear "normal" while the background remains blue. Then add full CTO to the talent, he will shift to orange.

Now add the 80A (blue) filter to the camera, which will correct the actor back to normal while the background goes effectively double blue.

As far as the sensor is concerned, it is still working with a straight up 3200 image (the talent) and the background is simply going blue, so you are not overdriving the red channel on the talent.

Again, you can experiment with different levels of camera filter and gel (simply use gel in front of the lens for your tests if you don't have access to different camera filters). I will say that the simple look of talent at 3200 with background at 5600 is not all that impressive, it's like the bad news photographer shooting a standup outside without adding the dichroic filter. The double-blue scenario described above is going to have more punch and look more deliberate.

Art Adams has a review of some new Schneider CTB Filters here: ProVideo Coalition.com: Stunning Good Looks by Art Adams | Cinematography (http://provideocoalition.com/index.php/aadams/story/schneider_ctb_filters/). It contains a good explaination of why one should avoid using tungsten WB. Admittedly he does use the RED as an example however it will be the same in any video camera. I have noticed that some cameras include a CTB filter along with their ND filters in the internal filter sets for this reason.

Aside from that I have to agree, the outcome is going to look pretty sad, exactly like something I go to some lengths to avoid. Given the choice with mixed daylight and tungsten light sources I'll go more towards the daylight as blue cast is visually ugly to the eye.

I'm no expert on grading however for a "cold" look I'd imagine you'd want to desaturate as well as maybe a slight shift to blue. This could be achieved without all the futzing around by forcing the background into the lowlights. A black scrim behind the talent would do the trick. Then in post it should be pretty easy to desturate the lowlights if not by tweaking in the camera.

.....His idea is to key the talent with an orange light to get a warmer skin tone than the background and make the background even colder in post, either green or blue. The idea is that with orange light on the faces it would be easier to make the rest cold without affecting skin tones. ....I think throwing orange light on the talent will only make this worse and will produce noise? In any case there are a couple of ways of going about that. You can either set the camera to day light and film with tungsten or set the camera to tungsten and CTO the tungsten lights. If the director really insists in doing that which way is better? Or should I just try to persuade him to drop the idea all together because of the blue channel problem? Thanks.

Yes, you should try to persuade him to drop the idea all together for several reasons in my opinion.

I don't think the noise is the issue. After following several of the excellent ideas presented here and he ends up not liking the color, what will you do then? I find the term "warmer" to be really subjective. And what will happen after compression?

John

. . . and then there's the "power windows" type of color grading in post. When clients have these kinds of requests you need to make sure they're paying! Test shoots, color grading experiments . . . it's all coming out of their pocket. Then the decision is their budget and how far they want to go vs. living with compromise.

Why not use the abilities of the camera to select the skin tone color and color correct or adjust just those colors compared to everything else in the image? In the picture profile you can very selectively choose any color and shift it's color while not effecting any other colors in the image. You could do this in Skin Tone Detail or Color Correction menus (or both for selecting and controlling more than one color)

I think you guys are afraid of your shadows.
It sounds like a fun look and it could work if done right.
Noise is not a problem worth losing sleep over.

The main issue will be isolating the talent so the warm light surrounds them enough so you don't have too much "blue spill, but maybe spill from behind would look OK.

I've done this plenty of times on interviews and it can be a great look.

Above all you need to test before the shoot.
Try it out, otherwise send him to me.