6x9 Negative: Agfa Record II with 105mm Apotar (1950's Folding Camera), TMY, D-76
Epson 4990 - Raw scan @2400 spi at 3 different heights, adjusted with the BetterScanning holder.
Same image with moderate sharpening.
Given that these Epson scanners have limited resolution (approx. 2300 spi for the v700 and 1600 for the 4990), it's best to get the full resolution out of them - especially when using Medium Format or 4x5 film.
A BetterScanning film holder costs another $100, or around 15% more money - and gets us around that much better resolution. To get more resolution, we need to spend a lot more money: a disproportionate amount, you might say.