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Russell H.
Russell H., Technician
Category: Digital Cameras
Satisfied Customers: 669
Experience:  Working with digital cameras & questions for nearly 8 years.
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I have just bought a used Canon EF 100 x 400 zoom lens, I

Customer Question

I have just bought a used Canon EF 100 x 400 zoom lens, I have seen photographs on line of a circular ring which appears to encircle the lens, however I don't know what it's called.
I also wand a lens pod but cant seem to find one long enough. Can you kindly help.
Submitted: 1 year ago.
Category: Digital Cameras
Expert:  Russell H. replied 1 year ago.

Hi, thank you for contacting My name is Russell. I will do my best to provide the right answer to your question.

I need to ask, before giving you advice and information:
By "lens pod," do you mean a lens-mount extender, a cylindrical standoff to increase focal length from a given lens?

The circular ring in question - does it have any markings on it, or directly adjacent to it if all it has is a tick-mark or reference mark on one side? if so, what are those markings? they can reveal the nature of the ring.