problem with new(ish) 80D and 400mm

[mitchmcc]

I bought a new outfit in May, including an 80D, a 1.4TC, and 400mm II.   I have been using it quite a bit, and never saw any problems until the other day.

I turned it on, and was trying to set the ISO and nothing was happening.  Same for trying to set the drive, etc.   When I looked through the viewfinder, it was black.    I could not for the life of me think of what was going on.

In trying to debug it, I did notice one thing.   When I re-seated the entire lens + TC at the body interface, everything started working.

I need to do more testing to see if this happens again, but I wanted to ask if anyone ever heard of such behavior, and what it might mean.

Thanks,

Mitch

[RobertTheFat]

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@mitchmcc wrote:

I bought a new outfit in May, including an 80D, a 1.4TC, and 400mm II.   I have been using it quite a bit, and never saw any problems until the other day.

I turned it on, and was trying to set the ISO and nothing was happening.  Same for trying to set the drive, etc.   When I looked through the viewfinder, it was black.    I could not for the life of me think of what was going on.

In trying to debug it, I did notice one thing.   When I re-seated the entire lens + TC at the body interface, everything started working.

I need to do more testing to see if this happens again, but I wanted to ask if anyone ever heard of such behavior, and what it might mean.

Thanks,

Mitch

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The obvious explanation (which isn't necessarily the correct one) is that the lens wasn't properly seated in the mount. There's probably nothing you can do unless/until it happens again.

You always need to be sure that a lens is properly seated. If it isn't, it can fall off when you try to zoom or focus.

[mitchmcc]

Agreed, but in my case, the lens was already mounted and I do not think it could have been dislodged. I will keep this in mind, however. Thanks!

[ebiggs1]

What exactly did you buy? An 80D along with a 1.4 tel-con and 400mm lens is an odd combo unless you have a specific goal in mind. Is all the gear real Canon and is it from areal Canon USA dealer?

The 80D should turn on with or without a lens attached.

If the lens and tel-con is third party it can be the cause.  If so, stop using them.

[mitchmcc]

It's all real Canon... I do use the TC with this outfit, and do get autofocus up to f8.

[jrhoffman75]

I seem to recall something about needing to install TC on lens first and then installing on camera. Not sure where, and not sure if this is your problem. 

[RobertTheFat]

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@jrhoffman75 wrote:

I seem to recall something about needing to install TC on lens first and then installing on camera. Not sure where, and not sure if this is your problem. 

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That does make some sense. If the camera can't identify the lens on its first try (which would presumably be the case with a freestanding TC), it might not know how or when to try again. I would not, however, expect that effect if the camera were turned off while the TC and lens were being installed.

[ebiggs1]

I seem to remember that the manual suggests you turn off the camera when changing lenses.  I have changed lenses in as many ways as is possible over the years and none seem to make any difference. I am not sure when the camera decide what lens is mounted. It may be as it shoots each shot and I believe that is true.

At any rate the camera will work whether it has a lens on it or not. Turn on, I mean.   It sounds like a full reset of the camera is next. Menu, Tools, clear all settings, etc.

[jrhoffman75]

"I turned it on, and was trying to set the ISO and nothing was happening.  Same for trying to set the drive, etc.   When I looked through the viewfinder, it was black."

I missed that the first time.  Sounds like something may have actuated mirror lockup or Live View (assuming lens cap was off lens )

[mitchmcc]

>>>>>Sounds like something may have actuated mirror lockup or Live View (assuming lens cap was off lens 

I will also look at that... I was wondering whether I might have accidentally hit some other button.  Thanks!