Camera problem with extension tubes

[Nsanti]

I am having a problem with my canon sl2 and andeer extension tubes with autofocus support. Whenever I change lenses with the extension tube still attached to the camera, the camera will not power on after the lens change unless I take out the battery, and put it back in.

[MikeSowsun]

If you use a voltmeter, you will find that even with the camera turned off, there is still power at the some of the camera lens contacts.

[jrhoffman75]

[MikeSowsun]

"Note that power is only supplied to the lens when the camera needs it to do something" 

This can't be true because voltage is present at some of the the camera body contacts, even with the main power switch turned off. 


Additionally, The 80D, and most other newer cameras, have a custom function for retracting the lens barrel on a lens after the power is switched off. 

[ebiggs1]

"... the camera will not power on after the lens change unless I take out the battery, and put it back in."

This is a red flag to me.  I would buy some real Canon tubes and not use those anymore. The camera doesn't like them.

[Nsanti]

after some more testing I discovered it really doesn't matter if the tube is connected to the camera or the lens. after powering off the camera and changing to a lens with the tube attached it won't power on unless I pull out and put back in the battery. I've come to the conclusion that the use of $15 tubes is not worth it to possibly damage my $400 camera.

does anyone think I caused damage to the camera by trying this. It seems to function fine now.

[John_]

I'd say from the odd symptoms you have described the potential to cause damage to your camera is real. You should quit while you're ahead and toss your tubes!

[ebiggs1]

"does anyone think I caused damage to the camera by trying this...."

It can't be good because Canon tubes don't do that.  It may not damage the camera but like you said $15 vs $400.  Why risk it?

[Nsanti]

Ok, thank you all for your help. I will try to get my money back / return them. I'm starting to wonder if extension tubes are right for me anyway since with the stock 18-55, focusing distance becomes right on the object at times.

[kvbarkley]

Look at the EF-S 60mm macro, I am exceedingly pleased with it: