figure out focal length
Posted 08 March 2011 - 08:53 PM
Posted 08 March 2011 - 09:51 PM
The field of view of a 25mm on S35 is about 51 deg, that's about 7mm on a 1/2" sensor. Dividing by 3.5 is close enough.
Conveniently, IF you could stop down by 3.5 stops on the 1/2", you would also get the same depth of field on the S35.
So, a 7mm length at F2 on the EX3 would look pretty much like 25mm at about F6.7 on the Red. Field of view and depth of field looking much the same.
Posted 09 March 2011 - 11:02 PM
Thanks for the shoutout, Hal. Actually it was created by Andy Shipsides here at Abel after I did the Sensor Comparison Chart. We each consulted with one another on how our projects should function and what they should show. Andy's far more computer savvy than I and was much better qualified to create the Comparator tool. I'd been saying for years that we needed something like this but didn't know how to do it, so I finally did the chart. Once Andy set his mind to his tool he had a beta version up in two days and the finished product within a week.
This page on Abel Cine's webpage should be helpful. It was created by Mitch Gross who works there and posts here from time to time.
Field of View Calculator
Posted 10 March 2011 - 12:54 PM