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Godfrey Dee April 6th, 2013 01:59 AM

White balance confusion
 
In the excellent article GETTING CREATIVE WITH WHITE BALANCE - WWW.URBANFOX.TV the 3200k preset is shown as more blue than the higher preset of over 5000k yet the color grading usually sets the lower k rating as redder

So when I get to shoot internal tungsten or even led lit interiors what should the preset be?

I should add that when I leave it to auto white balance I am not clear if the video camera is adopting the preset or adapting the white balance on its own.

Anyone can clarify

1 for interior shots will the preset be used even when adopting auto white balance?
2 for interior shots will a preset of 3200k produce a bluer or redder tone?

Allan Black April 6th, 2013 02:44 AM

Re: White balance confusion
 
What camera do you have? .. and welcome :)

Cheers.

Godfrey Dee April 6th, 2013 05:22 AM

Re: White balance confusion
 
Hi

Have a few z5s

Bill Ward April 6th, 2013 06:29 AM

Re: White balance confusion
 
Godfrey: you are almost always better off doing your white balance manually. That being said, pre-set auto white at 3200 for inside, and 5600 for outside.

As you can see from the urbanfox pictures, sunlight is bluer, incandescent is redder. So if you have the camera set on preset outdoors (5600) and shoot with an incandescent lightbulb, it'll look reddish/orange/yellow.

Go outside with the camera set at 3200 (inside)--or roll some video with a shaft of sunlight entering the frame, and you'll get blue video.

Sunlight is generally pretty stable, color temp wise. Sure, shadows can be a bit bluer than bright sun. Indoors, though, the color temperatures can be all over the place, because of the wide variety of lighting sources. I've had lamps that balance at 1100 degrees before...really warm! And some of the CFL lights can be really blue (and others show a sickly yellow-green sometimes).

One of your best bets is to get a set of Warm Cards from Vortex Media. They let you "cheat" the color balance a bit, (both indoors and outdoors) with much more warm, happy looks than displayed in the urbanfox article. Then, when you shoot, balance with the Warm Cards each time you set up in a new location.

Godfrey Dee April 6th, 2013 07:22 AM

Re: White balance confusion
 
Thanks Bill

This all arises from filming indoors where there were moving head LEDs of tricolour reds and blue washes. Camera was set to auto white balance but with preset at 5600k and the end result was oversaturated blues and reds . Have been advised to down shift to 3200k tomorrow with similar lighting but cannot work out if the preset kicks in even when on manual exposure and auto white blance.

I understand using our grey cards might sort this out so that white balance is fixed manually whole evening, although bit concerned what happens during speeches when washes turned off,
so is there any reason to use indoor preset of 3200k or, as I say, is that automatically in operation if we use awb?

Your input really appreciated.

Seth Bloombaum April 6th, 2013 09:44 AM

Re: White balance confusion
 
Theatrical lighting is a bit of a problem - color washes and so on that look good to the eye frequently are horribly oversaturated on video.

The color wash cannot be corrected through white balance. It's beyond the range of WB, and what you want is for the face to look like a face; it's the front lighting that counts.

Godfrey said: "Camera was set to AWB but with preset at 5600k..."
Both these cannot be true on the many cameras I've used. It's one or the other. AWB is a bad choice with background colors changing. Preset 5600k can be a good choice indoors when lit by LED or HMI/HID sources.

However, if you've been advised that the front light is at 3200K that would suggest that conventional lighting fixtures are being used, most often Lekos & Fresnels for theatrical and large conference/stage events.

Best: Ask the lighting operator to turn on the front lights and do a white balance.
Next best: Preset your cam(s) for 3200K
Worst: Use Auto White Balance, which will try to come up with the best white in the moment, looking at a scene which has changing colors in the background - ugh. Faces will change color as AWB tries to find the current white for the scene.

Oversaturation of backgrounds is a different problem, usually a problem for Production Management & the Client to solve. But often video recording is considered less important than what is happening for the in-person audience. Due Diligence suggests that you show your higher-up or client what the video looks like and ask them if it acceptable.

Godfrey Dee April 7th, 2013 01:22 AM

Re: White balance confusion
 
Thanks Seth

The conclusion I have drawn is that 3200k is at the redder end of the spectrum and as a preset counter balances the blue wash of any indoor lighting like moving head LEDs

However red led moving heads are likely to emphasise red 3200 preset and will produce red blemishes which is what happened

So the best advice internally must be to manually white balance off a grey card to avoid the effect of such awful colour changes. I was working with a z5 operator who set his wb to auto but still got good skin tones with those changing lights. i was also working with auto wb but the colour washes were terrible so thought the preset was the problem, but apparently it wasn't. So how on earth that happened is still a mystery.

Gary Nattrass April 8th, 2013 09:48 AM

Re: White balance confusion
 
I find that a hybrid white balance can be very useful these days especially when shooting LED lights as used on stage or theatre.

I tend to have three pre-sets on my camera 3200, 5600 and 4300 which is a mid point that is best for mixed light sources of tungsten and LED.

RED is a bad colour for video shooting anyway and it blows out very easily and can do more so on sony camera's as they don;t tend to have IR filters.

What may look OK to the eye can be very vivid on video so it is best to reduce any red lighting or introduce white light or other colours to balance it out, orange can be better too if you are able to control the lighting.

Even for old school film shooting red can be a problem and this film we shot for The Tube in 1985 had far less red light than is seen on screen:


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