lamiaceae wrote:
Likely countless times. It is of no practical value unless you have or plan to shoot with two or more different frame formats (sensor sizes). There are lots of sensor sizes FF, CF, 5/4, Medium, and many more. Other UHH'ers have explained some "rules". Most people are more interested in how different focal lengths vary on different sensor sized cameras.
I'm not concerned about the DOF difference between sensor formats in the slightest.