Depth of field for various formats and lenses

Started May 30, 2012 | Discussions thread
Veteran MemberPosts: 8,373
Re: Depth of field for various formats and lenses
In reply to amangupta, May 31, 2012

amangupta wrote:

... and adjusted the subject distance.


I hope I've not made a mistake above. What do you think?

That's your mistake but it wasn't fatal.

An important aspect of comparing images from different sized sensors is perspective, and perspective changes with distance. When this topic is discussed, the presumptions are:
same F-number
same distance
same field of view (meaning focal length must be adjusted by the crop factor.)

When these criteria are followed it's easy to see from the DOF calculator that DOF is more shallow on the larger sensor. It's because the focal length is shorter for the smaller sensor.

When working with a single format, yes, when focal length and distance are increased proportionally, DOF remains about the same as long as the F-number remains the same (within limits...limits that are far from the portraiture range of focal lengths.)


Reply   Reply with quote   Complain
Post (hide subjects)Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark post MMy threads
Color scheme? Blue / Yellow