I get that, Leigh. I was more questioning my measurements and configuration/setup.
Thanks for the reminder though of the basics (really). I've taken in a lot over the past 10 months or so (film photography, large format, developing and printing, new and old lenses, alternative processes, etc., etc.) and it's not yet second nature. Ma' brain is full... sometimes I need a refresher!
Here's the result (first test):
Found an old projector lens with four lens elements. Took the front one out, mounted it on the 4x5 camera (image circle plenty big enough), covered and uncovered it with a cap, and this is what I got! Well, there were a few more steps involved, but basically that was it. Guestimating about 200mm f/4, Efke 25