DOP meter

[JeremyLangford]

Is there a place online where I can see a depth of field meter for free that does the same thing as the one here that Expodisx makes?

http://www.expodisc.com/products/images/add/EN_42.jpg

Are all DOP meters the same?

[Curtis N]

try this site:
http://dofmaster.com

They have some free stuff and some pay stuff. Not sure about the rotary sliderule. Lots of info there, anyway.