I need some help on the use of the 5 switches on this lens . I just purchased it used, and it has no instructions with it . I understand the"range" and the" auto /man " , but how are the" Focus Preset/Set " "Manual focus speed 123" and the (o) whatever that is used??? Could any one suggest a book ? I would like to use the lens this weekend without screwing anything up !

Thanks , for any help on this , expecially if someone would take the time to explain these here .

D.C.

-- D.C. (dmconnell@charter.net), August 02, 2001

Answers

The AF / M switch obviously switches the lens between auto and manual Focus.

The Range switch obviously controls the range over which the lens will focus, either 3m - inf., 3m-6.5m, 6.5m-inf.

The Focus Preset/Set switch is spring-loaded, with off, on and the sprung set, positions. This allows you to focus on something with the switch in the on position. Slide the switch to the set position, and let go, so it springs back to the on position. Now focus on something else, and then turn the knobbled ring behind the focus ring and it will jump back to the focus distance it was at when you set it.

The ((o)) switch sets an audible confirmation of the focus preset system.

The focus speed switch controls how fast the lens manually focuses, since in this lens the focus ring communicates with the AF motor, and is not mechanically linked to the focus system. This switch controls the speed with which the system operates.

Play with them, and see!

btw, I don't own this lens. I've never handled one either. I found all this out by searching on the web. These two pages (esp. the first) told me all I needed to know:

http://met.open.ac.uk/group/cpv/photo/EF300_28L.html

http://www.photo.net/photo/canon/donb/300

-- Isaac Sibson (Isibson@hotmail.com), August 02, 2001.

Isaac, Thanks for that help !

D.C.

-- D.C. (dmconnell@charter.net), August 03, 2001.