If I render a preview (composition 1000x600) the aspect ratio on the monitor Decklink 4K extrem (external graphic board) is always 16:9. why??? is there a possibility to avoid this?
How are you connected to the Decklink?
What version of AE are you using (down to the last decimal)?
Why don't you make a 4x3 SD comp of a simple circle, run it through that board and tell us what you see?
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