Focus test chart and discussion on auto focus
Thursday, April 17th, 2008
Tim Jackson has posted a useful Focus test chart with a nice explaination of how to use it and what the various focusing problems are with lenses and users.
Canon users, don’t be put off by the “Nikon D70″ site title, the chart is useful for any brand camera and lens.
While this chart may not prove anything definitively it may lead you to taking a lens back to Canon or Nikon or Sigma to have it recalibrated. Or, it may show you where the auto focus sensors are in your camera vs. where the dots light up on your viewfinder when auto focus locks on a subject.
Whatever it proves, Tim’s done a great job of discussing the various issues related to focusing, and trust me, there are many.
