Mr Magic Carpet Ride's Blog

Digital Cinema/HD Video/Commercial Video Production

A Solution to Back-Focusing Problems With the Sony PMW-EX3 February 14, 2011

Filed under: HD Video — mrmagiccarpetride @ 12:08 am

Hello shooters!  I recently was heartbroken after reviewing footage from a recent concert I shot with my EX3 where I realized that my footage was soft when I zoomed out for wide shots.  This was particularly confusing because I was using full manual focus with no auto assist focus on and the subject was very sharp when zoomed in all the way.  I had never had a problem like this before with any camera and had never heard of back focusing.  After doing some research I found out that it is not necessary to do any updates to the firmware to resolve the problem as many forums were saying.  Steps to correct the problem are below…

1.  Set your camera to 1080i60 even if you don’t normally shoot this way, it will make the adjustments more accurate.

2.  Print out the located below “Back Focusing Chart” and resize so that it fits on an 8.5″ x 11″ piece of white paper.

3.  Tape the paper to a well lit wall as level as possible.

4.  Set up a tripod about ten feet (three meters) from the chart with the camera at the same height as the chart.

5.  Make sure your zoom is set to servo and not manual.  (Located on the bottom of the camera)  Zoom all the way into the chart so that it takes up the entire frame on the viewfinder.

6.  Set the camera to full auto focus using the focusing ring and the switch on the side of the lens.

7.  Go to the “Lens” menu in the main menu when your camera is in camera mode.

8.  Select “Auto FB Adjust” and the camera should begin automatically calibrating itself.

9.  If the test fails you might need to double check that you are shooting in a well-lit environment.

10.  Your camera’s back focusing problems are now history!

This helped me and I hope it helps you too.  You can also find several other back focusing charts by searching in Google, I just included this one here to save you folks some time.  Please feel free to comment or contact me with any questions.

Happy shooting!

Back Focus Calibration Chart

Mr. Magic Carpet Ride Productions Back Focusing Chart