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Regarding the extra channels for exporting: you may want them to be
- Embedded into the main output file if its format supports this:
- EXR, TIFF and MXI will embed all the enabled extra channels into the main render file.
- TGA and PNG can embed only the alpha channel into the main render file (RGBA). The rest of the extra channels will be stored in independent files.
- JPG, BMP, JPG2000 and HDR do not support embedding alpha or any extra channels. All the extra channels will be exported to independent files.
- Separate, getting independent files for all the required extra channels in all cases (available for all formats).
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Regarding the light emitters: you may want to store each emitter contribution to independent files or have them all as layers in one multi-layered file:
- Composite: all your light emitters will be stored as different layers in one multi-layered file, in those formats that allow multiple layers (EXR, TIFF and MXI). For the rest of the formats (TGA, PNG, JPG, BMP, JPG2000 and HDR) the emitters will be stored as independent files, as those formats do not support multiple image layers.
- Separate: you will get a collection of individual files corresponding to the different emitters in the scene.
Regarding to the extra channels exportation: you may want them to be
- Embedded into the main output file if its format supports this:
- EXR, TIFF and MXI will embed all the enabled extra channels into the main render file.
- TGA and PNG can embed only the alpha channel into the main render file (RGBA). The rest extra channels will be stored to independent files.
- JPG, BMP, JPG2000 and HDR do not support embedding alpha or any extra channels. All the extra channels will be exported to independent files.
- Separate, getting independent files for all the required extra channels in all cases (available for all formats)
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