How much can you crop a Red 5kHD image for a 1080P delivery? We were asked if it was possible to shoot a single camera Red 5kHD interview and extract both a wide and a tight shot from the footage. Like all tests the final delivery resolution and compression determine what is acceptable and what is not.
This test shows original 5kHD footage shot with 50mm, 75mm, 100mm and 125mm lenses. We then created equivalent focal length crops from the 50mm 5kHD footage. All footage was exported from Redcine X at 1920x1080 ProRes 422HQ. You can compare viewing here with the Vimeo compression and then download the ProRes 422HQ original file of this video to see how the compression affects the results.
Things to notice are an increased depth of field in the cropped images. We see questionable noise at full resolution when you go beyond a 100mm equivalent crop. But if you are shooting a single camera interview and need two frame sizes this may be a viable option. Our other observation was that composition for the extracted tighter frame is very important for this workflow to be successful. So plan the frames sizes on the shoot with your DP. Don't wait until the edit to decide to do this!