It is a good thing to tell users both, the
- actual focal length, and the
- 35mm equivalent focal length.
Not everybody cares about sensor size. But everybody cares about what photos can be made. Imagine the confusion if P&S cameras wouldn't mention their equivalent FL... Hey, it's even in the EXIFs...
New users just have to know that markings on an SLR lens always are the actual FL.
To add to the confusion, actual aperture and 35mm equivalent aperture differ by the same factor the FL does.
Last edited by falconeye; 10-27-2010 at 05:31 PM.