Save EXR

Saves a single-part EXR file from either an 8-bit image or EXR channel artifacts, preserving float precision in channel mode.

Category: EXR

TL;DR

Two modes: Mode A takes an ImageArtifact/ImageUrlArtifact (8-bit) and normalizes [0, 255] to [0.0, 1.0]; Mode B takes up to four EXRChannelArtifact slots and preserves float precision.
Mode B takes priority: image_in is ignored whenever any channel slot is connected.
Output includes an EXRPartArtifact descriptor for the written part, so you can chain straight into Display EXR Part.
A collapsed Metadata group exposes optional header fields (owner, timecode, comments, custom attributes, ...).

(image node) → [Save EXR] → Display EXR Part / Load EXR
Load EXR (channels) → [Save EXR]

Name	Type	Required	Notes
`image_in`	`ImageArtifact \\| ImageUrlArtifact`	No	8-bit image source (Mode A). Ignored when any channel slot is connected.
`channel_r`	`EXRChannelArtifact`	No	Channel to write as R (Mode B).
`channel_g`	`EXRChannelArtifact`	No	Channel to write as G (Mode B).
`channel_b`	`EXRChannelArtifact`	No	Channel to write as B (Mode B).
`channel_a`	`EXRChannelArtifact`	No	Channel to write as A (Mode B).

Name	Type	Notes
`output_file`	`str`	Path to the written `.exr` file.
`output_part`	`EXRPartArtifact`	Descriptor for the written part — connectable to Display EXR Part or Load EXR consumers.

Name	Type	Default	Notes
`compression`	`ZIP \\| ZIPS \\| PIZ \\| DWAA \\| NONE`	`ZIP`	Codec applied to the output file.
`pixel_type`	`HALF \\| FLOAT`	`HALF`	`HALF` is 16-bit float (standard); `FLOAT` is 32-bit full precision.

Name	Type	Default	Notes
`part_name`	`str`	`""`	Name for this EXR part.
`pixel_aspect_ratio`	`float`	`1.0`	Pixel width/height ratio.
`owner`	`str`	`""`	Asset owner.
`comments`	`str`	`""`	Free-text comments.
`capture_date`	`str`	`""`	Capture date (e.g. `2025-01-01T12:00:00`).
`software`	`str`	`""`	Authoring application name.
`time_code`	`str`	`""`	Editorial timecode (`HH:MM:SS:FF`).
`custom_attributes`	`str`	`""`	Non-standard header attributes as a JSON object.

Mode B wins. If you meant to save image_in but a channel slot is still wired, the image is silently ignored — disconnect the channel slots.
8-bit sources don't become HDR. Mode A normalizes display-referred 8-bit data into [0.0, 1.0]; it does not recover highlights. Use Mode B with float channels for real HDR data.
Pick DWAA for big beauty renders. It's lossy but dramatically smaller; keep ZIP/PIZ for data passes (depth, normals) where exact values matter.
FLOAT doubles file size vs HALF. Only use 32-bit when the extra precision is actually needed (e.g. depth or position passes).