What is the metric of comparison for DPI and the resolution of an image? I'm rendering a PDF to multiple JPEGs with Automator, and I'm wondering what DPI would be best to use?
If the JPGs are being used as assets for a video then the resolution (PPI/DPI) is completely irrelevant. The only time the resolution matters is if you are printing the images. The "I" in DPI and PPI stands for "Inch" and your video knows nothing of inches.
The de-facto standard for screen images is 72 PPI so if you have to pick one go with that, but it doesn't really matter. The only thing that matters is pixels, find out the size you need in pixels and output your JPGs at that size.
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