User Manual

Multi-Channel RED HDRx Support
The RED EPIC, SCARLET, DRAGON, and WEAPON cameras are all capable of shooting in an
HDR mode that effectively “brackets” two different exposures of each frame. The resulting
image data stores two channels of image data: the regular exposure, and a “highlight exposure”
that’s underexposed by a user-selectable margin (+3, +4, +5, or +6 ƒ-stops difference).
By default, the Input bar in the node graph feeds the regular exposure to your grade’s node
tree. To take advantage of the additional “highlight” exposure, you can add an additional
Source input to the node graph that feeds a second stream of image data that you can mix with
the regular exposure in different ways.
NOTE: You can also take advantage of the highlight exposure of RED HDRx media by
enabling and adjusting the Magic Motion controls in the Camera Raw palette.
To set up a node tree combining the normal and highlight HDR versions:
1 Using the first default node (Node 1), grade the image to see if you even need to use
the alternate exposure that’s available. We’ll assume for this example that you do. In this
example, the sky of the default exposure is pretty blown out, but there may be detail
that can be retrieved using the highlight exposure.
Using HDRx images with the Layer Mixer
2 Create a Layer Mixer node by choosing Nodes > Add Layer (Option-L), or press the
ADD LAYER button of your control panel.
Two nodes are created, a Layer Mixer node that’s added after Node 1, and a third node
(Node3) that’s connected to a second RGB input of the Layer Mixer node in parallel
to Node 1.
The Source currently supplies two input, but you can add a
second source, which is the short exposure in the HDR image
Chapter – 127 Channel Splitting and Image Compositing 2883