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Old Jul 17, 2008, 2:49 PM   #11
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Who. Me? wrote:
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How does the lens tell the body its focal length?

Will the body be able to obtain that information for older lenses?
Newer lenses have a chip inside that tells the camera what it's focal length is. This info is used by the sensor shift image stabilization system, is always placed in the EXIF data, and may also be used for theflash. Older lenses don't have this chip, so, as mtngal says, you can enter it manually into Pentax dSLRs.
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Old Jul 17, 2008, 4:39 PM   #12
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I don't know about Sony, but Pentax works the way TCav said. Auto focus lenses have electronics that tell the camera what it's focal length is. The lenses that are auto exposure/manual focus orcompletely manual do not. As soon as you turn on the camera with one of these lenses mounted, a scale comes up. You just scroll through to the right focal length (if it shows a different focal length)and the camera will hold that information, so that the next time you turn on the camera that number will come up. There's a way to change the focal length in the menu system, but I never use it.
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Old Jul 18, 2008, 7:56 AM   #13
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Thanks for clarifying.

Again, there wasloads of info listed on Google, and none of it answered the question!

Thanks

Andy
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