This is a feature (similar to one that Minolta had) that long ago earned the "Darwin Camera Award". In the early 90's Pentax, and Minolta in particular, came up with technological answers to questions nobody ever asked. At the time this feature came out many people claimed to be able to follow focus a subject, and if you could do this you can certainly manually zoom a lens.
BR From: [EMAIL PROTECTED] I was shooting my daughter's figure skating tonight and toying with the PZ's power zoom clips. I was thinking that it would be extremely useful for a sports photographer and thought I would explore them further. A lot of photographers and critics don't see a use for this feature but I'd bet that if you learned to use it prperly, that it would be very useful given the right circumstances...

