Exporting the render to a PSD file allows you to get all the render channels, the Multilight emitters and the composed image all embedded as layers in one single file.
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Render Courtesy of Riccardo Cecchinato
Due to the different characteristics of the available output formats, the required extra channels for exporting, and the Multilight options, you have a wide range of export options depending on the needs of your project.
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