Quote Originally Posted by Rick Olson View Post
Sandy ... is there some type of factor or estimate for getting the estimated "full" image circle compared to what is published by the manufacturer at f-22? The Fuji 360mm that I have at the top of this thread has an image circle at 485 at f-22. What might I expect the "full" circle to be? What type of shutters might limit the circle? Is that called mechanical vignetting? Are the Copal 1 shutters less prone to this due to their larger size?

Thanks,
Rick
The actual circle of illumination varies a lot even when we compare lenses of the same design, i.e. dagors, plasmats, etc. However, virtually all plasmats are capable of at least 70 degrees of coverage, and most are capable of 77 degrees or slightly more. However, the only factor I am aware of that you can use to determine actual coverage at the extreme limits for ULF work is the human factor, i.e. experience.

I am not personally familiar with the Fujinon L lens. Is this a tessar or plasmat type lens. If it is a tessar type the coverage should be less than for the plasmat type -W series, but it still should be enough to cover 7X17 with a couple of inches of movement.

Sandy King



Sandy King