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Old October 26th, 2013, 12:27 PM   #31
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Re: big white balance calibration target

Doug - thanks for coming back with more input.

Quote:
Originally Posted by Doug Jensen View Post
John, I'm not sure I understand the question you are asking. But if you are asking if you'd lose less light by white balancing on WarmCards vs. adding gels to your lights, the answer is yes. There is never any loss of light when white balancing with WarmCards or any other calibration target. But adding gels to your lights always dims them at least a little bit, and sometimes a lot.
Your assumption is correct as that was what I was asking about. This would be a good selling point; for using the cards over gelling.


Quote:
Originally Posted by Doug Jensen View Post
If the Cool Lights are as bad as you say, I'd probably add a 1/4 or 3/8 magenta gel to get them closer to normal, and then use the Minus Green card that comes with the set of WarmCards to clean up the color balance.
I don't know if they're "that bad" or if I'm very picky.

Question: If one wants to "save" all the light one can and not have it "lost" due to using gels, why not just use the Minus Green to begin with? Note: These LED floods really lose a lot with the 3/8 Magenta gels. These lights were originally intended for use indoors.


A little background:

I doubt these pictures will help because they look different on my screen now than they did on the monitor I was using at the time, after they were taken. Also, I *may* have also color balanced them a bit. These were taken about three years ago.

Here is one sample picture:
http://www.dvinfo.net/forum/attachme...-000_0722.jpeg

Here is another sample picture:
http://www.dvinfo.net/forum/attachme...n-000_0528.jpg

Both were taken with the CoolLights but I don't remember anymore what I used for gels. The pictures on my laptop that I'm using to write this don't really show any green tint
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Old October 26th, 2013, 04:46 PM   #32
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Re: big white balance calibration target

Quote:
Originally Posted by Paul R Johnson View Post
The point of the white balance is to make sure anything on set, that the camera can see that is white - looks white.
I used to believe this, but it's not totally true. White balance is subjective. For an extreme example, shoot a scene 5 minutes before sunset. With the sun behind your back, look at a white building in front of you. It should appear yellow-orange, not white. If a "perfect" white balance was performed in this case, the scene would look too blue.
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Old October 31st, 2013, 02:13 PM   #33
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Re: big white balance calibration target

Quote:
Originally Posted by Doug Jensen View Post
Bill, and that's why WarmCards have been so successful for the last 13 years and are used by cameramen all over the world -- they work great for all skin tones and races.

Now, if you really want to blow your mind, EXPOSURE is also the same for all skin tones. This is why an exposure for the lightest skinned Caucasian and the deepest shades of African skin turn out to be PRECISELY the same. When I'm teaching workshops this is a hard thing for some people to wrap their head around until I demonstrate it a few different ways. Then it all makes sense.
Uh, I'm kinda of the opinion that "warm cards" have been "successful" because they're a way to separate a lot of people from their money. Step back and its basically charging massive markup on something that's astonishingly (outside of marketing costs) cheap to produce - and therefore it's a WONDEFUL business model.

By nature I don't EVER try to force my field shots to achieve "a look" - it just doesn't make sense to me. In the studio, the light is fixed. And light changes so much over time during a typical outdoor shoot that if my goal was to come away with "matched lok" footage, I'd be constantly re-white balancing anyway - and potentially wasting massive amounts of time trying to match the conditions.

Waste of time IMO. (I know others feel very differently)

My priorities when I'm shooting are to achieve a properly exposed image with a white balance that's close enough. Then I immediately turn my brain to my videography and talent direction and the LAST thing I want to go back to fiddling with is field color correction.

I simply feel there are way too many things that are FAR more important for my brain to be engaged with than fractional color tones - something I can easily tweek in post - and something that's getting easier and easier to push around with modern NLE systems.

My 2 cents anyway.
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Old October 31st, 2013, 03:52 PM   #34
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Re: big white balance calibration target

Quote:
Originally Posted by Mark Kenfield View Post
To be honest, I think I've always had better luck (and more consistent results) by simply using WB presets for 3200k, 5600k and 4500k for times when I need to split the difference.
Sunlight or tungsten lighting, I might agree with this. But not shooting under discharge lamps (HMI, fluorescent, or LED).

Color temperature numbers deal only with the blue-orange axis. They don't relate to the magenta-green axis at all. Unfortunately, many discharge lamps have green spikes. This is why people in this thread are discussing adding minus-green gels in front of LED lights -- to tame that green spike.

Most modern cameras do a manual white balance function on both the blue-orange and magenta-green axes (and perhaps more besides -- who knows?). Doing a manual white balance under, for example, fluoros, can correct a nasty green spike if your fluoros are giving one. If you just dial in a specific color temperature number, the green spike goes uncorrected and shows up in post.

You're going to correct it in one place or the other. My personal preference is to correct it at capture time. I'm almost certainly going to tweak it in post, yes. But I'd rather start from a solid base. Maybe that's just me though, IDK.
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Old November 2nd, 2013, 06:30 AM   #35
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Re: big white balance calibration target

Quote:
Originally Posted by Bill Davis View Post
Then I immediately turn my brain to my videography and talent direction and the LAST thing I want to go back to fiddling with is field color correction.
That's what's so great about WarmCards -- it eliminates all the fiddling. Not only do WarmCards save you or your client a lot of time color-correcting in post, they also allow you white balance quickly, simply, and very predictably on-location so you can turn your brain to the other elements of the production. There's no guessing about the white balance, you don't need to check it on a field monitor, you don't need to ask for anyone else's opinion, you don't even need have a color viewfinder to know that you've nailed the white balance perfectly when you use a WarmCard.

If you're going to take 10 seconds to white balance on a white card anyway (and you should be doing that anytime you're shooting under man-made lighting!!), then it's a no-brainer to use a WarmCard instead and save yourself the hassle of grading the footage in post to make it look the way it should have looked in the first place. Even a simple correction like adjusting the white balance in post takes extra time, and why bother if you could have nailed it at the time you white balanced on the shoot?

Most cameras that are being used today only record 8-bit video onboard the camera, and anytime you do ANYTHING to 8-bit footage in post, you have degraded the technical quality of that image to one degree or another.

Another consideration is that a lot of DP's won't be editing their own footage. Most freelancers (including myself) turn their footage over to the client at the end of the project and have nothing to do with the edit. So, unless I have a sophisticated client who requests shooting in a RAW format or with an SLOG gamma, I want to make sure the Picture Profile settings, exposure, and white balance are as close to perfect as I can get them right out of the camera. When the client looks at my monitor at the shoot, or when they take a look at the raw footage back at their office, I want them to be blown away by the look I have achieved for them and not to think, "well, it's a start, but we can fix it in post."

For anyone who takes the time to actually do a test of their own and look at the difference between an interview shot with a normal white balance and one shot with a WarmCard white balance, there's no doubt which one you and client is going to prefer.

I'll be the first to admit that WarmCards aren't for everyone, but for less than a hundred bucks they can give you a better white balance right out of the camera and save tons of wasted time in post for years and years on hundreds of shoots. Not too many products offer that kind of ROI.

WarmCards - White Balance Reference System
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Old November 4th, 2013, 06:24 PM   #36
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Re: big white balance calibration target

Heck, every day people pay $2.50 for bottles of exactly the same fluid that comes from the sink a few steps away - and in test after test after test, the tap water from a decent municipal system is proved to be every bit as healthy and palatable as the bottled stuff. They're buying "convenience" and I get that. But sorry, I'm not buying that "warm cards" are about convenience. I kinda believe they're about insecurity. And a lack of real technical expertise.

If a shooter feels some deep compelling need not to accurately record the light falling on any face by white balancing ON that face in the traditional way - you can simply do what a lot of us have been doing for decades when we find ourselves in light that's too cool or warm for our tastes - white balance through a scrap of 1/4 CTO or 1/4 CTB gel.

But how you spend you money is your business in the end.

So good luck.
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