The HDRI command creates an HDR file, which is a good choice for export when touching-up the image in an imaging program; the exported image is “lossless” and will not have quantization artifacts when color or exposure is further adjusted after export.
To export a file in HDR format:
Select the rendering mode to use for the export (Artistic/Custom/Fast/Final Quality Renderworks) and render the image.
Select File > Export > Export High Dynamic Range Image (HDRI).
The Export Image File dialog box opens. Specify the dimensions and resolution for the exported image.
Click to show/hide the parameters.
Click Save.
The Export OpenHDR File dialog box opens.
Specify the export file name and destination, and then click Save.
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