All I know is that you need to have more than 2gb ram gpu to render out 4k images, which is not the case here…
Maybe Juan can help you out.
The thing I would try is:
A. Export to something else and see if that helps, ie dpx.
B. Try to export portion by portion of your timeline instead of the whole thing at once
C. Worst case; convert your source footage to something more lightweight, pro res hq for example and reapply the grades
Editor/Colorist, Amsterdam, The Netherlands
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