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Many prominent DPs in the “film days” didn’t use an 85 filter when shooting outdoors, whether for the sake of visual consistency (Alcott) or because they didn’t want to interfere with image quality (Elswit). They would instead correct the white balance in post.
My question is: Would shooting in digital LOG with your white balance kept to 3200 be the equivalent of doing this? Is there any benefit to doing this versus a correct white balance in digital?
I imagine you end up with less overall color information, so a slightly less rich and saturated image. I’ve heard some vague arguments for either way. Obviously not relevant if you’re shooting RAW and can re-target white balance in post.
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So you’re suggesting shooting daylight under 3200k and correcting it in your NLE?
White balance is gain in your B and G channels (dependent on filtration). In a typical Bayer CFA-type signal process, you amplify both red and blue channels dependent on the white balance; if you’re shooting at 3200k, a higher factor of gain is applied to the blue channel and so on and so forth.
Note, this doesn’t happen in the analogue domain but after demosaicing, when shooting non-RAW type codecs like ProRes or DNx.
Adjusting white balance in post is applying another level of gain to your R and B channels. I guess if you like the look, sure, but it’s an unnecessary level of gain and would lead to chromatic noise in some instances.
Even shooting RAW I try to get WB as I want on camera. It can be “correct” to the lights on set or not depending the effect we want to achieve. Same as green/magenta. I try to get as much in camera as I can.
It means everyone is watching a “final” image on set and it also means post will have less work and less chances to ruin it. As it has been told before, not every DP has the chance to sit down during color grading sessions. So the most final image you can get in camera the better.That is an interesting question. There was a distinct shift in the shadows when you pulled an 85 and shot a tungsten balanced stock in daylight. I did this throughout ‘Shawshank’ but only for specific scenes of other films. As I understand it the Alexa was, originally, more sensitive to blue light. I certainly did some side by side tests before I shot my first film with an Alexa but I found little, if any, discernible difference between shooting for a tungsten and daylight balance.
If you are recording Arriraw on the Alexa, white balance is only metadata anyway. The sensor is naturally “biased” towards preferring daylight, i.e. it is less sensitive to blue so likes light with more blue wavelengths, so when you convert the Arriraw recording to RGB for a 3200K scene, the blue channel is being boosted in comparison to the others to balance the color for 3200K lighting.
If you record log-C with a color temperature selected, then that color temperature is “baked in”, meaning that if you set the camera to 3200K, then the camera is boosting the blue channel to compensate for a lack of blue signal.
So it is a bit like chasing your tail to shoot in daylight with the camera set to 3200K, record log-C, end up with the camera boosting the blue signal off of the sensor and creating a blue-ish daylight scene, and then in post, lowering the blue channel back down to correct the image to daylight-balance. It may turn out OK, but keep in mind that you’d be taking a recording where the blue information was needlessly boosted and then having to lower it again while boosting the red information to compensate. When you bake-in color temperature, it’s more of a WYSIWYG scenario, you only have the colors you see to work with in post. So you have to ask yourself what you are gaining by recording more blue than you need and less red than you want. Unless you actually want a cold day look.
I think film is similar but also different, even if you shoot daylight on tungsten-balanced film (which is film in which the blue layer is faster to compensate for a lack of blue in tungsten light), you are still recording information in each color layer, so red information can be recovered depending on your base exposure.
” Is there any benefit to doing this versus a correct white balance in digital?!”
No. You could make tests but I don’t see this resulting in anything desirable.
Lately if been pondering the reverse of your idea. What if I set my digital cinema camera to 3200K and then use an #85 or #85B as filtration? I was wondering if it may have a pleasing effect on skin tones or other “warmer” elements of the frame. Something I will test soon.
Cinematography Student
Filmakademie Baden-WürttembergI did a similar quick test once with a blue filter in order to see if it’d help with day-to-night conversion. Shoot raw to be able to visually losslessly change white balance in post.
I couldn’t see a difference between using the blue filter and using no filter but turning WB to a higher Kelvin in post.
Modern cine cams are so good at balancing temperature, would be interesting to know if you’ll see a difference at all with that test.
Lately if been pondering the reverse of your idea. What if I set my digital cinema camera to 3200K and then use an #85 or #85B as filtration? I was wondering if it may have a pleasing effect on skin tones or other “warmer” elements of the frame. Something I will test soon.
I think mainly you’ll just find that your blue channel got noisier, which is how a digital camera takes a raw conversion to RGB and makes it 3200K. There may be a subtle difference in the color values due to the dyes of the optical filter… but the question is whether that could just as easily be created with minimal color-correction.
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