Monitoring image exposure

Livegrade offers various industry-standard tools to judge the exposure of image signals.

In this article, you will get an overview of Livegrade’s

Display modes to alter the pipeline’s processing state,
Exposure assist to quickly analyze luminance values of an original signal, and
Scopes to measure the luminance and colors of an image.

Display modes#

The display modes “Original”, “Bypass”, and “Graded” allow for altering the processing state of the image. This can be useful if you want to quickly check the coverage of details in the highlights or in the blacks (by using “Original”) or to see how the image would look without the color adjustments of your look (by using “Bypass”).

Display modes overview#

Graded shows the image in the processed state, i.e., after all nodes of the look have been applied.
Bypass shows the image without color adjustments but already converted to the display referred colorspace. All color adjustments will be disabled and only the last output transform will stay enabled.
Original shows the picture unprocessed. No part of the look is applied in this state.

Accessing the display modes#

Changing the display mode can be done

for each slot individually (via the slot view or the slot settings)
for each output individually (via the output settings)

Tip: Livegrade provides Stream Deck and Tangent controller actions for changing display modes.

Exposure Assist#

Exposure Assist allows for quickly checking the exposure of an original, unprocessed camera signal by colorizing certain luminance values into certain color schemes.

Let’s go through the different schemes:

Exposure assist overview#

False color: Those color schemes are designed by camera manufacturers. They respect the underlying log format and use the same ranges and colours as the respective camera does when using its internal false color mode.

EL Zone: The color palette for this exposure assist tool was invented by Ed Lachman and is widely used throughout the film industry. Livegrade offers EL Zone for the most common log formats.

Black and white: This scheme transforms your coloured image into a black and white representation in order to get luminance values only.

Setting up exposure assist#

In order to use a specific scheme for a certain log format, exposure assist has to be set up first within Livegrade’s “Grading” settings.

There, you have the possibility to select the exposure assist LUT, which should be applied when enabling “Exposure Assist”.

Tip: If you are working on a mixed camera setup, you can also assign an individual exposure assist LUT to a slot.

To learn more about setting up exposure assist, please find the corresponding article here: Using exposure assist.

Accessing exposure assist#

Exposure assist can be enabled via

the toolbar to enable it for all slots at once
the slot view to enable it for one input slot
the output settings to enable it for all sources shown in the output

Tip: If you have multiple video output devices available, you can configure one of Livegrade’s outputs to always show certain cameras with activated exposure assist by using the “Force Display Mode To” option. This would enable continuous exposure monitoring of your camera signals, whilst your input slots can still be used in other outputs for grading.

Scopes#

Livegrade provides several video scopes in order to measure luminance and color values of your image.

Scopes overview#

Livegrade comes with a set of typical video scope tools:

Waveform,
histogram, and
vector scopes.

The scopes always process the image currently shown in the selected output. This can be a live signal, a recorded clip, a still, or even a multi-view.

Tip: The video scopes always analyze the currently processed image. In order to see the scopes of the original image, switch the display mode to “Original”.

Accessing scopes#

The scopes can be found as a tab within the slot panel in the bottom-right of the main screen.

Within the scopes, you find several settings to

show a certain scope tool (Waveform, histogram, vector scopes)
set the unit for the Y axis (IRE or nits)
and others.

To read more about all settings, please find the corresponding reference article here: Scopes.