LRTimelapse Forum

Full Version: Add support for Open EXR files
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Hi Gunther, given your disinclination to shoot bracketed HDR timelapse due to the hassles, I wanted to offer this workflow as an example for you to try out purely for the sake of color quality and see if it interests you. If so, maybe you would want to add EXR support to LRTimelapse.

Example workflow:

1. Shoot bracketed HDR timelapse
2. Batch process in Photomatix to merge bracketed photos and export as 32 bit OpenEXR in Adobe RGB or ProPhoto colorspace.
3. Bring EXR files into After Effects
4. Using AE OpenColorIO plugin, transform ProPhoto/Linear to ACEScc
5. Apply color corrections Lumetri plugin
6. Apply final OpenColorIO plugin transform from ACEScc to Rec709 or sRGB as preferred

Suggested workflow using LRTimelapse assuming OpenEXR support could be added:
Steps 1-2 above
3. Use LRTimelapse to deflicker EXRs - to do this, LRTimelapse would need to add support for:
a) Reading the EXRs (not difficult using open source OpenEXR library)
b) Ideally, add a way to LRT to properly display the EXRs - to do this, perhaps use OpenColorIO (also open source) to build in a few preset transforms for displaying the EXRs in LRT:
- Typical input spaces: Linear / [AdobeRGB | sRGB | ProPhotoRGB]
- Typical output spaces: ACES 2065-1 (RRT) to Rec709/BT1886, or just straight through to 709/1886

Just adding support for reading EXRs (#3) would be enough to leverage LRT solely for EXR deflicker and sidecar XMP, in which case the EXRs could be loaded into After Effects, to proceed with steps 3-6 for further color grading.

But optimally if OpenColorIO was also in LRT, then the images could also be displayed in a pleasing way in LRT so the user could also do other basic exposure adjustments across the timelapse sequence.
Additional details for OpenColorIO in AE:

Import EXR sequence and add to comp
Apply OpenColorIO plugin to sequence layer
Set plugin to:
Aces 1.01
Convert mode
Input: Utility > Linear RIMM ROMM ProPhoto (or Adobe RGB or sRGB - whatever you chose from Photomatix output)
Output: ACES > ACEScc

After the first OpenColorIO add a Lumetri plugin for color adjustements. Leave it at defaults for now.

Then after Lumetri add another OpenColorIO plugin, settings:
Aces 1.01
Convert mode
Input: ACES > ACEScc
Output: Output > Rec709 or sRGB (depending on your monitor)

Then, to start color adjustments, depending on the way your exposure was bracketed, you may need to set the Lumetri plugin with an Exposure adjustment or +1/+2

From there adjust Lumetri with color wheels and curves etc.

This workflow provides very natural and high quality HDR images with beautiful color.
As far as I know, Adobe Camera Raw (and therefore also Lightroom and Adobe DNG Converter) don't support those files.
As long as that's the case, I won't be able to add that support to LRTimelapse.
There is a 4 years old feature request on the adobe site: but I don't think this is going to happen, since with DNG Adobe has it's own format, which is HDR capable.