6b5f7abd_Indigo_Manual__1
[2] Once a rendered image is displayed, you can click Save Image to save it to disk in a number of standard formats such as PNG or JPEG, as well as the special Indigo Image (IGI) format for resuming the render later; the PNG format is recommended since it doesn't degrade the image quality as JPEG does. [1] 
Save Image
Indigo Manual
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