On Fri, 16 Mar 2001, Evan J Dong wrote:
> On the Macro lens, it has two (2) aperature ring on it . The range
> runs from F22 to F4. Any reason as to why it had two aperature ring
> and are eah ring supposed to go through the entire range form F22 to
> F4.0? It appears that this lens is only stop down metering. No Auto /
> Manual switch.
Correct. The auto-stop-down feature didn't arrive until the introduction
of the Auto-Tak's. One of the aperture rings will let you set an aperture
without physically stopping the lens down. Then when you are ready to
take the photo (or want to check the DOF), you manually turn the other
ring until it meets resistance at the aperture that you set the first ring
to. The first ring acts as a sort of guide. If you set it at, say, f8
and then turn the second ring, the second ring will only go as far as f8
before meeting resistance. This way, you can stop down to the correct
aperture without looking at the lens each time. So you, you have to
manually stop the lens down and open it up. Fun, isn't it? :)
chris
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