I am using standard definition 1:33 ratio clips in a 1080i blow-up (with black bars on the sides, of course). Should I ask Premiere to interpret the 720x580 standard footage as 1080i non-anamorphic or should I use SpeedGrade to reconstitute the image to this same standard?
Is it advisable to retain the clips original lower frame first or should I accept the upper field first standard for high definition?
It is advisable not to uprez, unless you have a good deal with the local ophthalmologist and you get a nice % of his new business from your viewers. If you really need to uprez, use RedGiants InstantHD.
I have to agree with Harm that unless you need to mix the SD footage into an HD project for some reason, best to stick with SD. When done right, SD footage on DVD can look very good on an HD TV, when using a DVD player or Blu-ray player that upconverts to HD and connects via HDMI. Take that same SD footage into a Premiere HD project and burn to Blu-ray and it does not look so good at all.
Also, SD footage is typically not 1.33 anamorphic, and SpeedGrade is for color grading and has nothing to do with standards conversions.
If you can tell us the workflow/purpose of this adventure, we may be able to offer more specific guidance
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