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05-09-2012, 11:39 AM   #1
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Function of P A AS switch on FA zoom lens

Recently bought a FA 28-105 power zoom lens from another forum member. Can some one tell me what is the purpose of the P A AS switch that is on the barrel?

I guess I don't have much use for it on my K5? Just curious to know what it is meant for and how it works. Also, in which mode should I leave the switch when paired with my K5?

Thanks for your replies.

05-09-2012, 12:01 PM   #2
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The only power zoom functions supported on DSLRs are power zoom and lens retraction. The fanciness (or not) that that switch is for won't work on your K-5 (it only works with PZ series film cameras).

Details on the other power zoom features are found here:
Pentax Lens Power Zoom

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05-09-2012, 12:08 PM   #3
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Aha - thank you for the explanation. Features 4 and 5 are also really cool. Why didn't they implement these two in the K5? The PZ model seems to have had some advanced features compared to the K5.
05-09-2012, 01:06 PM   #4
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5. Zoom Effect Mode The lens will automatically zoom from wide angle to tele during exposure thus creating a special effect where the subject diffuses radically outward.

That sounds pretty cool. I'll have to try that (manually) sometime.


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