I will try my best to be specific, since this question could easily dive into a broader topic. Here is some useful context, followed by my question at the end. I shoot Delta 100 on 4x5, in DDX, for my landscapes. I use the RB67 Sekor-C lenses for casual studio work. I have been wanting to consolidate and I've been considering the Fujinon GX680, mainly because of the film size and camera movements. It, allegedly, also has superior optics to the Sekor-C's. I realize grain is subjective to a certain point, but I routinely wet print my landscapes up to 16x20 and I simply prefer a less grainy print. I shot and printed a test landscape to 16x20, taken with the 90mm Sekor-C (Delta100, DDX). My goal was to see if the 6x7 film size would be 'acceptable' enough for me to sell the 4x5 I have clearly been spoiled by the 4x5 film as the 6x7 grain, even at 8x10 print, just wasn't as fine as I expected. So, no offense to the 90mm Sekor-C ... but I am wondering how much of the grain was an optical limitation, rather than a film size limitation. My Question: Would the, allegedly, superior optics of the Fujinon GX680 lenses give a finer grain compared to the RB67 Sekor-C lenses? I wish I could rent a GX680 & Lens for comparison, but they are scarce enough as it is.