Quote -   Any particular preference for wanting your render that large? It will add a significant amount of time to smoothing out a render to 'crispness'.

Well, 3840x2400, that's a mere 9.2Mp's, kind of tiny compared to what's considered to be 'normal' for digital photographs these days, even for smartphones. Besides, imaging technology that only allows me to make postage stamp sized prints (@ 300 ppi) goes straight into the bin. With these images I'm trying to find practical limits.

Generally I'm prepared to wait if the results are worth it, but unfortunately for now there's only one way to find out if they ever will be, and that's to wait...and wait...and wait ; )

Cheers!