White balancing on the BMCC

I'm sure this would have been covered somewhere else before, but I'm new here, so sorry for potentially repeating previous threads. Anyway, I just wanted to know if anyone has any advice on how best to white balance the BMCC for each new location? I know the best option would be to buy a light temperature meter and do a test in the room to get the correct kelvin reading to put into the camera but, without spending the best part of a grand on such a device, is there an easier and just as reliable way of doing it? I have installed the light spectrum app from Itunes onto an Ipad, but I seriously doubt the effectiveness or accuracy of such a thing. I mainly shoot RAW on my camera, which I know would normally mean that the white balance doesn't really matter that much as you can just change settings in Resolve. The problem here is that I'm going to be filming both interior and exterior scenes within the same project, so I can't simply change the overall settings to something like Tungsten or Daylight, but instead to 'As Shot'. Yesterday I experimented with a simple shot of someone sat on a sofa. It was during the day, but overcast enough to make me turn on a Tungsten lamp in the room. I also have two Bipolar LED lights, which I initially set to 3400K each, along with setting the camera to this (to match, the best I could, with the lamp in the room.) I then re-shot the scene, this time changing the LED lights and camera to 5600k, to try and match the light coming in through the window. I then imported the footage into resolve, set the overall settings to 'As Shot' and added the same grades (the BMD and Arri Alexa ones) to each shots. both ended up looking wildly different (the Tungsten shot footage looked much better than the daylight set ones.) So, any tips or advice on how best to set up the camera's white balance when shooting RAW for editing in Resolve would be much appreciated. Thanks in advance.

I've had this perverse way of working that doesn't involve white balancing on set.

I trained shooting on film first and we only had 5600K or 3200K.

So instead you balance the LIGHTING to match your camera. Or you used colour correction filters in front of the camera to correct the ambient lighting to one of those preset white balance settings.

This is still how I work today. I use 5600k or 3200K and then adjust my lighting to suit from there. There's so much room in 12 bit ProRes (which is mostly what i shoot) that it's easy to adjust / grade around any camera to camera inconsistencies.

What I've found previously is that if I chase WB scene to scene it actually makes it MORE DIFFICULT to grade because it's trickier to match shots. When you shoot at the same WB, you then are letting the lighting float and that seems to be easier to get matching shot to shot and scene to scene.

I also am mixing colour temperature more and more.

It used to be you'd NEVER have 5600k Daylight in a room with 3200K tungsten lighting on the foreground but now I do it all the time.

Here's some test shots I did for the show I'm doing now.

These are shot RAW on a stills camera.

I have a 3200K Quasar tube as the key lighting the face and then above and behind the subject is a daylight 5600K quasar tube.

Then in Capture one, I simply switched the WB from 3200K to 5600K. So in one shot you'll see the "correct" WB on the face but the bg is very blue.

In the second shot you'll see the same photo where the backlight is more neutral but the key light on the face is now quite warm.

Which one is right ?

I think it depends on what MOOD and story you want to tell. I think it's important to realise that though we THINK we want things to be CORRECT and RIGHT and ACCURATE it's often the case we want to invoke a mood or tone. I can imagine stories where both of these "looks" would be appropriate.

Amazingly if you sit the WB at about 4600K - 4800K on this shot it looks the most neutral which is kind of sitting on the fence

So what's the right WB here ? 3200K for the key ? 5600K for the backlight / background ? Or somewhere in the middle ?

I say it's up to you to choose for what you're trying to achieve. Also, shooting RAW or a 12 bit ProRes makes this much easier to change later on.

https://flic.kr/s/aHsmdixwnq

JB

Hi John
Many thanks for your excellent reply and link to photos. I really like what you said about keeping the white balance more simple and only using 1 setting for Tungsten and 1 for Daylight. One of the reasons why I chose the BMCC is that I felt it was one of the few digital cameras which came closest to shooting on film. If the Arri Alexa is the camera which comes closest to 35mm, then the BMCC is the one which comes closest to 16mm (in my view anyway.) If I'm trying to emulate the look and feel of film then sticking to two main white balance settings would be similar to only having two types of film stock. I think you can sometimes get overwhelmed with so much choice in these cameras and having so many Kelvin settings to go through for the white balance just complicated things a bit for me. I also get a bit worried that if I shot a scene in one location and then, for whatever reason, needed to go back to do one or two re-shoots or pick up shots, it would be difficult to try and remember or replicate the exact white balance settings from the original shoot and I would risk having mismatched shots in the edit (o.k, I should really be slating each take, with a reference to white balance etc, but in real world, low budget filmmaking this sort of thing often gets forgotten.) I did some more test shots today, with the same set up (natural daylight coming through the window and a Tungsten lamp on, next to the subject.) I just stuck to two settings (5600k and 3200k.) After a bit of colour grading I prefered the 5600k footage. I think that the daylight was much more overpowering that the table lamp in the room. I did also have my two bipolar led lights, which I adjusted to each setting for the different shots. Thanks again for the help. Very much appreciated.

If you’re not shooting for broadcast or handing off your media to anyone else for grading, then your intent is more important than a neutral white balance. I sometimes shoot with a higher temperature just to add a bit of warmth to the image. You might play with that too. If the lighting is 5600, shoot 6000 or 6500 for example. If the lighting is 3200, try 4000 or 4500.

I should add that I’m shooting raw, and it works for me, but it might be different shooting ProRes.

Sent from my iPhone using Tapatalk

I have numerous colour temp meters but have been impressed by this relatively low cost meter by Illuminati.

https://www.bhphotovideo.com/c/product/1383810-REG

No affiliation

JB

IMO outside of events and such where the color is supposed to be more or less natural, whether you're doing the finishing yourself or handing the footage off to a colorist/finishing artist, the mood and intent are the dominant factors.

I also suspect that John Brawley's method described above is a lot more common than he implied. I rarely change my white balance either, preferring to light to suit the mood rather than tweak white balance let alone worry about what's real -- it's a movie, a fictional world, and as the DP it's not your job to simply record it, it's your job to create the world that that director envisioned for his/her actors. Ergo, reality is what the DP+director+editor+colorist devise (no intended implication of priority there).

That said, if you want a light meter that can in fact measure color, check this one out:
https://illuminatiinstrumentcorp.com/

I've tried it, and found that it worked quite nicely. I was filming a band and wanted to capture them with natural color, so I measured the scene with my Illuminati meter and used its reading to set the white balance on my camera. The result was nice, pleasing skin tones.

I also used it to calculate exposure for another production so that I didn't have to power up my camera to find out.

I'd too like to chime in on the Illuminati lightmeter. Got four of them, great tools. I'm still testing out how its WB reading correspond to my UM46ks custom white balance.

And I too recommend keeping your WB the same during shooting a scene within the same setup. But if you change lenses and IRND filters you might have to redo WB.

I have that Illuminati meter as well. For the price point, it's pretty amazing.

I tend to work the way JB described above, picking either 5600K or 3200K and then sticking with it.

However, sometimes I get hired for quick turn around projects that will not get a color grade, and in those cases I really do need to nail white balance in camera.
Because the white balance and tint numbers in the menus on BMD cameras yield highly variable results between units, it's not possible to just rely on a light meter to simply read the scene lighting temp/tint and then set the camera menu to match. Different lenses and filters also add another set of variables as well. The meter can give me a rough idea, but when I need perfect white balance in camera I need to take a different approach.
The only reliable method that I've found to deliver perfect white balance in a single camera or to accurately balance multiple cameras or different lights on set, is by using an RGB parade scope on an external monitor as described here by Art Adams:
https://www.provideocoalition.com/art-manual-white-balance/

It would be great if someday an Ursa Mini firmware update added RGB parade as an option to display on the camera LCD.

Jamie you can work out an offset from a normal setting.

So on my current four cameras I have for daylight @ 5600k it’s...

A 5700k +6
B 5650k +17
C 5300K -5
D 5200K -2.0

JB

Jamie you can work out an offset from a normal setting.

So on my current four cameras I have for daylight @ 5600k it’s...

A 5700k +6
B 5650k +17
C 5300K -5
D 5200K -2.0

JB

Right! Good point JB. Thanks!

Just did a quick test:

Afternoon sun at 03:00 pm
UM46k with Tokina Cine 50-135 T3 @30° T11 and ISO 400 + Schneider True-cut IR 680

Illuminati light meter reading: 5384K Duv +0.002
Camera auto WB on Colorchecker target: 5850K +12
Also double-checked against RGB parade on Shogun Inferno.

I have to dig deeper how to interpret Duv values into UM46k's tint value.

Hi Robert,

Are you also using a ND filter in that shot? Does the Schneider IR cut influence the tint?

Ryan, I couldn't finish testing in sunlight, but I did some further testing now indoors:

Tungsten light source
ARRI ARRILITE 750 Plus (OSRAM G9.5 HPL 750W lamp)

Illuminati light meter reading
3050K Duv +0.000 / full flood @ 1m 16200 lx

URSA Mini 4.6k Tokina Cine 50-135 T3 @90° T11 and ISO 400
With Schneider True-cut IR 680 WB on Colorchecker target: 3100K / Tint -2
Without filter: 2950K / Tint -9

Tungsten ARRILITE 750 Plus NO IR Correct WB.jpg (374.13 KiB) Viewed 5297 times

Tungsten ARRILITE 750 Plus with IR Correct WB.jpg (367.5 KiB) Viewed 5297 times

Tungsten ARRILITE 750 Plus NO IR with IR WB.jpg (374.12 KiB) Viewed 5295 times

Tungsten ARRILITE 750 Plus with IR Incorrect WB.jpg (367.54 KiB) Viewed 5295 times

Thank you for posting the results Robert! It is an interesting question how Duv numbers correlate to different +/- tint new BMD menu. It’s possible that the ratio could also vary by camera.

EDIT: BTW I've seen testing online which correlates 1/8 +/- green gel as equal to .004 duv, quarter green gel = .008 duv, and half green gel = .016 duv

If you are flipping between the first two images you will see that the IR filter does eat a little bit of brightness, maybe 1/4 stop or less. And the infrared wavelengths have strong influence on the blue violet patches. With the IR filter it gets the correct color like it should.

[CaptainHook]

The only reliable method that I've found to deliver perfect white balance in a single camera or to accurately balance multiple cameras or different lights on set, is by using an RGB parade scope on an external monitor as described here by Art Adams.

I personally think one of the best methods is to use a neutral card and use the auto-WB in camera. It's not always practical though but if you can its fast and accurate.

Yes, but the Micro Cinema and BMCC do not have an auto WB!
Cheers

Great tip, but the original BMCC and the Micro cameras do not have an auto WB.
Cheers

LED light source
Dedo Dedolight DLED7-D (90W daylight version)

Illuminati light meter reading
5724K Duv +0.002 / spot ~15° @ 1m 16250 lx

URSA Mini 4.6k Tokina Cine 50-135 T3 @90° T11 and ISO 400
With Schneider True-cut IR 680 WB on Colorchecker target: 5850K / Tint +11
Without filter: 5800K / Tint 7

So you see with a light source without any infrared spectrum the differences between IR filtration and no filtration is within a small margin. It is also that the in camera auto WB is quite spot on with the light meter reading.

I personally think one of the best methods is to use a neutral card and use the auto-WB in camera. It's not always practical though but if you can its fast and accurate.

Good point. Yes, if all I need to do is balance Ursa Mini to existing lighting, then I do take advantage of the auto-WB function and it's been working quite well. It's great to have it as an external button on the Pro.