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.

[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:

[Waddizzle]

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@ebiggs1 wrote:

"The camera should be turned off when you mount and dismount any lens,..."

You know I used to think this was true but I don't anymore.  The last pin to make contact is the power pin.  The first one to break contact is the power pin.  Once the lens is turned a tiny amount, power to the lens has been removed.  Now there may be some reason inside the camera that doesn't like being on when changing lenses but I can't imagine what or why?

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Turning off the camera is what Canon recommends.

Note the bold text near the bottom of the page inside of the first blue box.  Does it seem to work with the camera on?  Sure, but that does not change the fact that the recommended procedure is to turn off the camera.  Doing so helps to protect the inside of the camera from accidents.

[John_]

There is a constant supply of power to the lens when the camera is on, It's the surge produced when that power is abruptly interrupted that could feedback into those tiny, sensitive electronic components within the camera to be concerned about. It's sort of like playing Russian roulette. 

[jrhoffman75]

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@John_ wrote:

There is a constant supply of power to the lens when the camera is on, It's the surge produced when that power is abruptly interrupted that could feedback into those tiny, sensitive electronic components within the camera to be concerned about. It's sort of like playing Russian roulette. 

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Yes. It's just good practice to power down electronic equipment before connecting or disconnecting accessories. 

[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. 

[Nsanti]

I just returned the tubes. It's not worth risking my camera, and I'm not even sure extension tubes were right for the type of lenses I own. I have always turned off the camera before changing lenses. These tubes acted funny even though the camera was off.