Maximum push-in and still be at 1080p?

[TonySegreto]

Okay -- I'll see if I can explain my findings and experience.

Based on a Resolution only approach, it appears that you can push-in/blow-up/scale up/reframe a 4K image to 213% for the purpose of retaining and outputting at 1080p Resolution. This is based on Adobe Premiere Pro CS 5.5 and After Effects CS 5.5.

I have actually found that the better approach rather than blowing it up from a 4K sequence is to reduce it from 4K to a 1080p Sequence. And here is my step by step process:

• Edit your sequence at 4K in your editor (I use Avid)
  • If you aren't editing in Premiere Pro Natively, Import to Premiere Pro or After Effects as a 4K Sequence and relink to R3D using EDL or AAF
• In Premiere Pro or After Effects create a New Sequence that is 1080p
• Open your original 4K sequence and Copy the entire timeline
• Open your 1080p Sequence and Paste your entire timeline
• Now you have a sequence that only show the middle of the R3D image
• Now you know exactly, in terms of resolution, how far you can push-in/scale-up/reframe
• Scale to Taste
  • For 4K 16x9, to scale down to 1080p -- 47%
  • For 3K 16x9, to scale down to 1080p -- 62.5%

Now, this doesn't account for losing resolution due to the Bayer Pattern Sensor. But as far as pixel for pixel up-scaling, this is a method that has worked for me for a couple years.

Let me know if this doesn't answer the above questions and I'll try to clarify.

^^ ^ This is what I do as well. I feel like its best to work off of this frame, than to manually resize in your NLE.