This may have an obvious answer, but I haven't worked with 4K r3d files before and wanted to verify all this.
I was asked to grade a short film shot on RED. The footage is 4K, but the final output will be 1080p. The editor told me he was planning to give me footage in 1080 to grade. My initial instinct was that grading in 1080 is less desirable than 4K, but will this really matter when the output is 1080 anyways?
Main question: is it better to grade in 4k first, then output to 1080? Should I ask him to send along the r3d files and I can reconnect via EDL?
You're correct. There are certainly advantages to conforming from the raw, which extends well beyond just resolution. The questions are whether they have the r3d avaialable, how simple or straightforward the conform will be, and whether the gain in resolution/range/flexibility is worth the performance hit.