How to expose correctly using the False Color tool

Many low-end monitors don’t have important exposure aids like waveforms, vectorscopes or even Zebras. But there’s hope.

One of the most popular tools for exposure using an external monitor is the False Color tool. In this lesson we’ll learn:

  1. what a false color tool is,
  2. why not all false color tools are created equal, and
  3. how to expose correctly using the false color tool.

What is False Color?

False color is a visual representation (on overlay) of where your exposure levels lie using color.

FalseColorH

E.g., every part of the scene that is at 100+ IRE is a certain color, let’s say RED. The region between 40-50 IRE, or middle grey, is in PINK, etc. This way, you just have to glance at the monitor to know exactly where your exposures lie.

In theory.

Are all False Color tools the same?

Both the Marshall and the SmallHD DP6 have false color, but they differ greatly. First, here’s how the DP6 shows false color:

DP6FalseColor

Now here’s how the Marshall does it:

MarshallFalseColor

Notice the difference? The Marshall has far more divisions for greater control over your exposure. How so?

Imagine you’re following the wolfcrow system, and need to expose skin tones to 60-70IRE in S-Log2. Using the DP6, you’re out of luck, because anything from 58-97IRE is going to be green. There’s just no way you can distinguish which is which on the field.

However, if you’re using the false color tool in the Marshall, the region from 60-70 IRE is going to be light grey. If you’re not shooting in S-Log2 but in Rec. 709 (any of the cine modes except S-Log2 and 800% Rec. 709), then you can expose for dark grey, with green and pink being your ‘borders’. This helps you to distinguish between the greys.

Even if you can’t distinguish between the various shades of grey, you know any yellow and red on your main subject is a warning. For studio swing, you must stay within 90 IRE (white point) so you would be careful not to get orange or red. If you’re shooting in full swing (100 IRE) you will try to avoid red. If you’re shooting S-Log2, you can go all the way to 109 IRE, and there is no further color to let you know when you’ve clipped 109 IRE. The region between 100-109 IRE is called ‘super whites’.

Therefore, when you buy a monitor for its false color, make sure what you’re getting, and whether it will be actually useful for the kind of shooting you’re planning to do.

A Study of the False Color tool on the Marshall 7″ Monitor

I’m going to be using the Marshall false color tool for this study. What are we looking for? I’m going to expose a scene with the Zebra shown (from the camera) compared to the false color on the monitor.

There are three likely outcomes:

  • They match, and we know for sure the false color tool is viable for exposure.
  • They don’t match, and we can’t rely on false color.
  • They match in some places, not in others – then we should be careful of our use of false color

As a reminder, from the video on exposing S-Log2, here are the zebras on the A7s:

ZebrasA7s

Let’s start with the Movie mode. Here’s a scene exposed using Matrix metering (f/2, ISO 320, 1/50s). The Zebras are at 70, the lowest setting (click to enlarge each photo):

1

Some of what the camera thinks is between 60-70 IRE is shown as 75-85 IRE (in yellow on the wall).

How about 800% Rec. 709? This scene is at f/4, ISO 3200 and the Zebra is set for 100+:

2

Obviously, the camera doesn’t think any part of the wall is over 100+, while the Marshall obviously begs to differ. This is a much wider difference!

False color is supposed to work well with Rec. 709, but it doesn’t work very well with non-standard Rec.709. Let’s test this further with S-Log2. Here’s S-Log2 with Zebra on 70 (f/2.8 ISO 3200, and the meter reads as +3):

4

What the A7s thinks is 60-70 IRE is interpreted as 75-85 IRE by Marshall. This is bad news.

Here’s the same scene with Zebra set to 100+:

3

No surprises, because S-Log2 does hold a lot of highlight detail. We need to push this scene further, so I overexpose by +5, at ISO 12800, Zebra at 100+:

5

They agree, but not perfectly. The A7s is obviously calibrated for its ability to show super whites all the way to 109 IRE, while the Marshall is not made for that.

For reference, here are the zebras from the camera. It will allow you to check if each color on the false color chart matches its zebra value:

FourZebras

Who’s correct? I don’t know, but I prefer the A7s because the engineers who developed it probably knew what they were doing – and, I verified the zebras using a waveform.

Finally, let’s test the wolfcrow system, which is to expose a zone using the spot meter by +3. In the scene, I have exposed the grey wall within the circle to +3. ISO is at 8000, and the Zebra is at 70, as I recommended:

6

Obviously the camera considers anything between 60-70 IRE under 70 Zebra, while the Marshall doesn’t think so. However, the Marshall is able to clearly show the exposed region correctly, which is a relief.

How to expose using the false color tool on the Marshall monitor

You can use the false color on the Marshall but it’s not perfect. I would only use it to judge middle exposure, even in the wolfcrow system. This is how it relates:

  • 70 IRE on the camera (wolfcrow exposure) = light grey and lemon yellow (60-85 IRE)
  • For Rec. 709, stay between the green and pink regions (dark grey band). Pink is supposed to be optimum, but that depends on how you like to expose, so I won’t recommend to blindly follow it.

That’s it. It can’t help you with the highlights clipping. The shadows are not a problem in S-Log2 anyway because everything is over 10 IRE.

My personal take

I know this result is disappointing.

I wouldn’t (and don’t) depend on only false color for exposure. This is why I recommended using the zebras on the camera so you can double check – especially with the wolfcrow system.

I strictly prefer waveforms and vectorscopes over any other method. Nothing else is as accurate!

Note: To expose using the false color tool in the Atomos Shogun, refer to the Shogun guide in Module F.

Click on the link below to the next lesson or head over to the main menu (above). If you need help with something, feel free to send me an email. I’ll try to get back to you as soon as possible.