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Has anyone used a tele-extender?

Started by dconra12, 12/01/2009 12:30PM
Posted 12/01/2009 12:30PM Opening Post
Has anyone used a camera manufacturers tele-extender? I have been thinking of getting the canon 1.4x extender upon occasion with a 100mm f9 scope. Does anyone have experience and what were the results?

Posted 12/17/2009 12:14AM #1
If you mount the extender, but without an EF lens in front of it, your
camera will show error 99 and not take any pictures at all.

The reason is that the extender has a small pin on its camera side mount
that indicates to the camera the presence of an EF lens. But when the camera
then tries to read out the lens information there is none ... the extender
itself does not qualify as an EF lens, it has zero electronics in it.

An t-mount adapter does not have that pin and thus the camera will realize
there is no EF lens and go into manual mode - thus all is fine.


Posted 12/17/2009 08:03AM #2
Televue now makes a 1.5 extender similar to the TAK Extender-Q. Not sure if it's only for TV scopes though. The diameter of the extender may only fit the diameter of their focuser. It does accept the 2" nosepiece of your camera. Check their website for all the info.