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Silly question: Correct way to do White Balance for the scene


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#1 Martin Hong

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Posted 28 October 2011 - 10:30 PM

I am going to shoot short with different scenes, there's one in particular, taking place in a house during day. When a woman opens the door and the guys enter, you can see the woman in her back and the guy's face, background not too overexposed, then she closes the door both walks into a room (camera follows them with pan) Room lit with tungsten light, and the tungsten lamp can be clearly seen in the shot.

So how to solve this abrupt color temperature change from daylight (still not sure if there will be direct sunlight on the man or shade) to tungsten, also i might have exposure problem to solve. The lamp in shot surely wont have enough power to match outdoor's light.

Also there's a scene in a small room with tungsten light with the warm feeling, what would be the best: Set WB to tungsten then color correct a bit in post or, set the WB to a higher number to make the scene look warmer? or the last option is too risky?

And what do you guys do the most? White balance with color temperature setting on the camera or manual set with a 18% gray card?


Any advice or help will be appreciated!! Thanks!

Edited by Martin Hong, 28 October 2011 - 10:30 PM.

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#2 Hiren Kachchhy

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Posted 01 November 2011 - 04:08 AM

Hey Martin. You forgot to mention which camera are you going to be shooting with cus then we can work out whether you can do an iris pull or not hence solving your exposure problem.
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#3 Phil Rhodes

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Posted 01 November 2011 - 04:33 AM

Extreme solution - shoot at night, light the exterior for daylight simulation?

If you don't want to see a colour shift exterior to interior (which might be OK, in some aesthetics), light the interior with daylight-balanced equipment - fluorescents, HMIs, etc. You'll still likely need a stop pull.

P
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#4 Martin Hong

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Posted 03 November 2011 - 12:42 AM

Hiren, sorry forgot to mention that, I am using Canon 60D with CineStyle profile, with these prime lenses 35mm f2, 50mm f1.8, 90mm f2.8 (Macro 1:1) and another super zoom from Tamron which i think i wont use it that much due to the sharpness issue on this lens.

Phil,
We are gonna be shooting the whole day, so daylight scene will be done during day, and night during night.. Plus dont have enough equipment to the daylight simulation.

I am mainly using fluorescent and will be counting with some Gel that i have requested, if i recall correctly these are:

Daylight Conversion Filters (Amber)
Cinegel #3407: Roscosun CTO
Mired Shift +167 Converts 5500K daylight to 2900K. Preferred either for a warmer look or when daylight is over 6000K. Optically clear. (Transmission = 47%).
Cinegel #3410: Roscosun 1/8 CTO
Mired Shift +20 Converts 5500K daylight to 4900K. Used when a very slight warming correction is desired. Deep-dyed base. (Transmission = 92%).

Both used on a 6500K 105W CFL with 500W effective output, #3407 to convert it to tungsten 3200k and #3410 to convert it daylight 5500k, if i did the right math.


PLUS
Cinegel #3314: Tough 1/4 Minusgreen
Mired Shift N/A Reduces the green output from fluorescents and other discharge sources. Deep-dyed base. Equivalent to CC075 Magenta. (Transmission = 81%).
or
Cinegel #3318: Tough 1/8 Minusgreen
Mired Shift N/A Reduces green output from fluorescents and other discharge sources. Equivalent to CC035 Magenta. (Transmission = 89%).

to reduce the green spike from flourescents

Also will have some 4000K and 3200K CFL, will have to figure what to do with these... Combine with some tungsten lamps that will be seen in shot or as refill.

Maybe i should directly change the light sources that will be seen in shot and try to have less color shift?
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#5 Matt Read

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Posted 06 November 2011 - 03:52 PM

Given the equipment you're working with, I'm not sure why the outside to inside transition is a problem for you in the first place. If the fixtures you have to work with are primarily daylight balance, there's no reason that you need to convert them to tungsten for interior work. You can just WB to daylight and use the uncorrected (or corrected down to 5500K, depending on what your WB ends up being) 6500K CFLs or 3200K sources gelled to daylight to light the interior. If you are worried about matching existing practical tungsten sources in the location, either gel the existing bulbs or replace them with daylight balanced ones. This will end up working better for you anyway, as I assume the room you are shooting in will have windows and you will therefore not need to worry about blacking them out.

However, if there's something I'm missing and you need to shoot the interior under tungsten-balanced light, you could do either of the following:

The most simple solution would be to eliminate the pan as the men walk into the room and shoot it as two shots with different WBs.

A slightly more complicated solution would be to shoot the shot as you originally described, but shoot it twice, with different WBs, from the same camera position and use a foreground object to hide a cut during the pan.
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#6 Martin Hong

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Posted 07 November 2011 - 12:31 PM

Hey Matt, thanks for the input, I will keep that in mind for the next time. We shot it yesterday and end up having a different solution, basically split the shot so we won't have to do the follow up.

In my opinion wasn't that bad the final result, did some color correction and grading, these are the results of the works in progress
MVI_4114 (0-00-29-00)35%BLUEBLEND.jpg
Posted Image
Posted Image
Posted Image

The first 3 screen caps belongs to the last scene with the police at the crime scene, Day, interior. On the right side you can see the windows with green curtain, daylight shade, interior was lit with Tungsten, 4x60w tungsten lamp, one CFL 125w (effective output), with Rosco Frost as the key on both actors.

The last one belongs to the scene where the guy sneaked up into this women's house and got caught, was shot during day too. With the sunblind down, one key light of a 500w 6500K CFL, with CTO 1/4 and on the other side as fill with a 175w 6500K CFL also with 1/4 CTO. Camera balanced to tungsten then later color graded in that way. Initially I wanted it to be shot at night, so the scene would have some moonlight coming in through the blind and the place should look as if there was no light on. But due to a production problem we had to shoot it quick.....

I got more screen caps for now, just to have an idea of the final result, let me know what you guys think. The short is a crime thriller
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#7 Mei Lewis

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Posted 11 November 2011 - 03:20 AM

Looks good.
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#8 Hiren Kachchhy

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Posted 15 December 2011 - 09:11 AM

Hey Martin. So sorry for not getting back to you. I just got to my computer today.
Anyways looks like your situation worked itself out :) The screen caps look great!
Cheers!
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#9 Martin Hong

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Posted 18 December 2011 - 03:06 AM

Hey Hiren,

Well we had several issues, because we got kicked out and had to shoot it fast so the final result is not what expected. Also i am still trying to get the best result from DSLR and apparently CineStyle is best solution for the lack of video control of DSLR?
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