How to use Katz Eye - MF Focus Technique

Discussion in 'General Technical Discussion' started by davewolfs, Jun 7, 2007.

  1. davewolfs


    May 23, 2006
    Hello everyone,

    I am sure many of you have used a manual focus screen or Katz Eye. That said, I am hoping some of you can share how the split prism works. From what I can tell so far, the prism in the middle will align when in focus, there is also a circle that is around this prism that looks almost like a bunch of smaller prisms. Could someone please explain the purpose of this screen?

    Also, when you are not dealing with an image that has any identifiable straight lines, what is the best way to tell if you are in focus or not?


  2. moffo


    Oct 20, 2005
    Central TX
    The circle of smaller prisms will appear sparkly (for lack of a better word) when out of focus and nearly transparent when focussed. Better than the split-prism for targets that don't have straight lines. Try it with a fast lens until you learn what you're looking for.
  3. davewolfs


    May 23, 2006
    Just tried with my new Zeiss 35/2. All I can say is wow. Talk about smooth focussing on that thing.
  4. ckdamascus


    May 14, 2005
    New Jersey
    Oh wow, you got the new ZF mount Distagon? How is it?!? I heard it was really good! I want to get one of those! :)