I am setting up a Premiere project for a film that’s just begun production and we’re shooting in 4K (Not UHD). We’re not sure yet if the film will finish in 4K, but we will be making a 2K DCP at the very least. Some other deliveries will likely be in 1920x1080, but we want to keep our options open.
We are transcoding footage rather than using Premiere’s proxy process.
Should we be transcoding to 2048x1080 or 1920x1080 for our editing process? Is there a significant difference in these choices?
First thought here is that your primary consideration is which editing codec you're transcoding into - that'll be a big factor in terms of data rate, from there, depending on how your system handles 2k vs. 1080 data rates in that codec, go from there.
For me, in terms of 2K v 1080, it's nice to be able to get a decent sense of what reframes and zooms are going to look like in the offline as well as how sharp focus is on shots, so choosing the highest resolution that works nicely in your system is a nice to have luxury. Linking your transcodes to your online media, if you storage allows for it, is a great way to cheat that in Premiere as you can seamlessly switch back and forth between online and proxy/transcoded version.
It does add a step though.
You're probably not going transcode into a finishing (full colour value) format, so transcoding to 2K to meet your 2K DCP shouldn't factor in I don't think?