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-   -   Where is better to WB? (https://www.dvinfo.net/forum/sony-xdcam-ex-pro-handhelds/473513-where-better-wb.html)

Giannis Pass February 24th, 2010 12:07 PM

Where is better to WB?
 
Hi, i have the Ex1r and i need your help.
According your experience, what is better?
A white paper, or a grey card for White Balance??
I am doing 100% weddings and i am using tungsten lights.
Thanks

Olof Ekbergh February 24th, 2010 01:22 PM

A white card is the best.

http://www.bhphotovideo.com/c/product/300868-REG/Porta_Brace_WBC_White_Balance_Card.html
These are great, if you buy a Portabrace bag they come with it.

You can also get a warm card selection from Vortex media, they are really good. They are both pure white and skin tone enhancing:
Vortex Media: VIDEO & PHOTO Tools and Training

Michael B. McGee February 24th, 2010 07:15 PM

yeah, maybe someone can explain using a gray card as opposed to a white card. i've never understood that technique. it is called white balance for a reason after all, right?

Roddy Jamieson February 24th, 2010 07:24 PM

Whether grey or white it does not matter as both have no colour. I often balance on the grey sky on an overcast day. So as long as the card is neutral you will get an accurate balance. If you use warm cards they have a slight blue tint to increase the red end and warm up the picture.

Michael B. McGee February 24th, 2010 07:28 PM

Quote:

Originally Posted by Roddy Jamieson (Post 1490631)
Whether grey or white it does not matter as both have no colour. I often balance on the grey sky on an overcast day. So as long as the card is neutral you will get an accurate balance. If you use warm cards they have a slight blue tint to increase the red end and warm up the picture.

in my experience, just this past weekend, there is a difference between white and gray cards. on on overcast day, i got 5600K on a gray card and 7100K on a white card. i used the 7100K WB

Malcolm Hamilton February 24th, 2010 08:38 PM

I had to shoot an interview today, and the whole office/workshop was lit by overhead flourescent lights. I have only tungsten lights, so 90% of the light on my interview subject was tungsten. When I white-balanced on my subject, the background was so blue it hurt, so I went to a preset, that gave me a much nicer background. Problem was, my subject was a slightly odd colour. I didn't know how to fix it... Was there a way? (I know that maybe I should get some flourescent lights in my kit). Would a grey card help?
thanks, Malcolm
P.S. I'm eager for answers, because I have to shoot at the same place tomorrow.

Richard Crowley February 24th, 2010 09:17 PM

Quote:

Originally Posted by Michael B. McGee (Post 1490635)
in my experience, just this past weekend, there is a difference between white and gray cards. on on overcast day, i got 5600K on a gray card and 7100K on a white card. i used the 7100K WB

Were they "official" white and gray cards? :-) Note that much of the "white" paper, cardstock, etc. we see and handle every day is "enhanced" with chemicals to make it look "more white", particularly recycled paper as people are demanding more "green" products.

Olof Ekbergh February 24th, 2010 09:35 PM

If at all possible turn off the fluorescents, or at least block as much of them as possible then light with your lights.

If using tungsten lighting also try to block all daylight, it will be very blue.

Sometimes the best way to shoot an office is at night and then completely light it with your kit.

I have big pieces of black fabric and sound blankets I bring on location to block unwanted light.

I know this is a tough situation and you may not be able to control it as much as I suggest, but give it a shot. If you have a step ladder you can actually just pull some of the over head bulbs, or have a janitor do it. At least around the talent. Shoot tighter shots and pay close attention to the back ground.

Tim Polster February 24th, 2010 09:47 PM

Quote:

Originally Posted by Malcolm Hamilton (Post 1490669)
I had to shoot an interview today, and the whole office/workshop was lit by overhead flourescent lights. I have only tungsten lights, so 90% of the light on my interview subject was tungsten. When I white-balanced on my subject, the background was so blue it hurt, so I went to a preset, that gave me a much nicer background. Problem was, my subject was a slightly odd colour. I didn't know how to fix it... Was there a way? (I know that maybe I should get some flourescent lights in my kit). Would a grey card help?
thanks, Malcolm
P.S. I'm eager for answers, because I have to shoot at the same place tomorrow.

If you can not control the office lighting, then you need to adjust the light you put on your subject to match the color temp of the office lighting.

This is done by using lights that are closest in color temp to your source and by the use of gels to change the color of your lights.

Offices are often around 4100k so you could gel a tungsten instrument with a 1/2 CTB (color temperature or "to" Blue) gel or a 5600k instrument 1/2 CTO (color Temperature "To" Orange) gel to get close to a match.


Grey cards are used more in the photo world. This seems like an odd crossover as the CMOS chips take over the video world.

I use the $5 Porta Brace white card you can buy at B&H. They work well and are cheap so you can by a few and keep thim in your cases.

I cut one up to a smaller size to fit in a shirt or jacket pocket.

Marcus Durham February 25th, 2010 04:53 AM

Quote:

Originally Posted by Malcolm Hamilton (Post 1490669)
I had to shoot an interview today, and the whole office/workshop was lit by overhead flourescent lights. I have only tungsten lights, so 90% of the light on my interview subject was tungsten. When I white-balanced on my subject, the background was so blue it hurt, so I went to a preset, that gave me a much nicer background. Problem was, my subject was a slightly odd colour. I didn't know how to fix it... Was there a way? (I know that maybe I should get some flourescent lights in my kit). Would a grey card help?
thanks, Malcolm
P.S. I'm eager for answers, because I have to shoot at the same place tomorrow.

You really need to be carrying some daylight gels in your lighting bag.

However Colorista is a great tool for digging yourself out of holes like this. You can colour correct just part of an image. In many large offices it is impossible to turn off the lights without turning off the entire floor, or block daylight. So I get myself as close as possible using gels on my lights and then colour correct the subject using the tools in Colorista.

Colorista is so cheap (200 dollars) there isn't an excuse not to have it. It really is a problem solver. The ability to colour correct just the portion of the image you need is just fantastic.

Yes I know Apple Color can do this, but it is an utterly painful package to use and Colorista is just far quicker as you can make your changes in the timeline in just a few seconds. Invaluable.

But for goodness sake, buy some gels!

Malcolm Hamilton February 25th, 2010 07:14 AM

thanks for the advice, everyone. I'll use gels today (because I have them) and look into Colorista. Very interesting. Malcolm

Giannis Pass February 25th, 2010 09:13 AM

Ok,
but what are most of you, use?
White card or grey card?
I am asking because some times i have seen very cold pictures, but the WB was ok.
Maybe a warm card solve this problem.
Thanks

Paul Cascio February 25th, 2010 11:59 AM

White or gray is fine as long as they truly reflect equal amounts of red, green and blue. If it looks white, it's probably white. However, gray can be tinted slightly, resulting in a misread by the camera's white balance function.

David Heath February 26th, 2010 03:51 PM

Whether the card is grey or white is immaterial, as long as it's neutral. I suspect that some "grey" cards may not actually be grey at all but have a coloured bias.

What is more important than the exact card is how the white balance is done - at simplest this can mean do you do it in shade or sunlight out of doors?

Mixed lighting is another problem, and lighting in offices has already been mentioned. My advice would be if possible to turn all fluorescents off, if that's not possible to try and balance your lighting to them for colour temperature, and if all else fails colour balance near your main subjects face and let the background go to whatever. It's the skin tones that are most important.

Fluorescents come in different types, and the most common seem to vary depending where in the world you are. In the UK, the norm seem to roughly correspond to tungsten, and normally tungsten lighting matches fairly well. In hotter countries it seems more usual to have fluorescents that roughly match daylight, and it's interesting that around where Tim works the norm seems to be halfway between the two!

You need to take a colour balance in the natural lighting, see what the camera says for colour temp, then gel your lights to roughly suit, then re-balance to your lighting as a general rule. Your lighting will look right, the background should be close enough.

Gints Klimanis February 26th, 2010 04:12 PM

Quote:

Originally Posted by Paul Cascio (Post 1490950)
White or gray is fine as long as they truly reflect equal amounts of red, green and blue. If it looks white, it's probably white. However, gray can be tinted slightly, resulting in a misread by the camera's white balance function.

Most grey cards are not certified to be spectrally-balanced, but they are useful for many exposure readings. Paper products usually yellow with a short exposure to bright sunlight or brown with dirt dust.

I bought two packs of Kodak Gray/White cards before I realized that I should just pay for something that lasts: WhiBal plastic card. I find that I only use the 8x11" card for white balance. Sometimes, I can convince my wife to carry the smaller one and include that in a picture.

Digital Photography - RawWorkflow.com - WhiBal Certified Gray Card for White Balance

What is unbelievable about this site is the dizzying array of product combinations and price points. I wish the fellow would cut the price of his large card and offer the three sizes or a three card kit.


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