19" Goerz Red Dot Artar Coverage for 12x20 Format
I can not speak for the coverage of a 19" Goerz APO Artar for 12x20 but I can speak for the Red Dot version of this lens. I have used this lens on my 12x20 many times and it is one of my standard lenses. Obvoiusly each individual lens will vary some, but my 19" red dot will cover 12x20 completely at infinity with some movement. HOWEVER, no matter how much you stop down the lens, the corners will not be sharp for an inch or so. BUT if you shoot at shorter distances than infinity, the image will be sharp corner to corner with movements. Attached below is an image shot with this lens in the vertical orientation at a distance of about 20 feet from the subject using about 2" of rise on the front standard. The image is sharp corner to corner even using a 7X eye loupe on the negative.
Originally Posted by sdivot