Originally posted by pres589 If the DA*55 didn't cover the full image circle presented by film or the K-1's sensor, vignetting wouldn't be removed simply by stopping down the lens, right? It'd be a hard edge of black that was always present, right?
Vignetting can be resolved by stopping down in many cases. The image circle of some lenses grows a lot when stopped down. This is especially important to large format photographers who need to use camera movements to secure depth of field. It's pretty easy when tilting the lense forward to run out of image circle, stopping down is how to get it back.
The way you could tell if an image was going to be vignetted was to take off the film back and look at the lens from the corners. If you could see the entire aperture, it was a safe bet that there would be no, or at least minimal, vignetting.