Changing Lenses with power on dangerous to Memory Card?

I was just speaking with someone who was told that you can cause damage to your memory card if you change lenses with the power in the "on" position. I've changed lenses many times and I rarely ever turn my power switch off, and I've never had any damage, but is it possible?

No,

Only if you get it squashed between the lens and the body, not if its actually in the camera!!

You shouldn't change lenses with the power on because the sensor is charged up. All the dust resting around it will be sucked onto the filter.

Did the person who told you that work @ Ritz Camera? HAHA

scot079 wrote in post #4160566
You shouldn't change lenses with the power on because the sensor is charged up. All the dust resting around it will be sucked onto the filter.

Did the person who told you that work @ Ritz Camera? HAHA

I've heard this said, but I've never believed it. The sensor is behind both the shutter and the mirror at this time. I can't see how either the electrostatic field can pass through these (the mirror at least must be conductive due to the metallic coating), or how the dust could reach the sensor through them. Can someone enlighten me please?

Edit: I mistyped shutter, and got bleeped! Tee hee.

scot079 wrote in post #4160566
You shouldn't change lenses with the power on because the sensor is charged up. All the dust resting around it will be sucked onto the filter.

Did the person who told you that work @ Ritz Camera? HAHA

I'm not familiar with this filter you speak of. What is its purpose, and where does it live?

So you are saying that one in fact should take turn the power off before changing lenses?

EWek11 wrote in post #4160760
I'm not familiar with this filter you speak of. What is its purpose, and where does it live?

The filter in question is the anti-aliasing (aka low pass) filter that is a fixed part of the sensor assembly.

I almost always change my lenses with the power still on and have never had an issue with my 30D. Then again, I can pretty much leave my 30D on most of the time since it goes to sleep which seems to be the same as the off position

I changed lenses numerous times with power on. I don't know whether it is harmful but everything is still working. Hell, I even openend the shutter to get a lens in a higher diafragma, decoupling it from the camera with the shutter still open.

It's a crazy world!

scot079 wrote in post #4160566
You shouldn't change lenses with the power on because the sensor is charged up. All the dust resting around it will be sucked onto the filter.

i believe thats been proven false, the electric field around the sensor isnt strong enough to pick up any dust.

I never understood the whole, don't change lenses when the power is on because the sensor is charged, thing.

If dust gets in the chamber while you're changing the lens on it's trapped in there. Once you turn the camera back on that dust is going to stick to the sensor anyways.

anyway, the sensor is only charged up during use - taking photographs, and liveview.

I taken off a lens or two by accident with the camera on

I've been going for years without shutting the camera off during lens changes and haven't experienced any problems with any of my cameras or cards. As far as shutting the camera down during lens changes to avoid dust on the sensor - like others have said - the shutter's in the way. And even if you were to shut the camera off, dust would still get into the mirror box and be attracted to the sensor the next time the flipping mirror stirred it up and the open shutter exposed the sensor.

Also I never turn my camera off. I just let it go into sleep mode and tap the shutter button when I'm ready to go.

The only bad time to change the lens when the power on is when you're outside and it's raining... Shoot, justing being outside when the camera exposed is bad enough unless you have a 1D. Even then, I'd still protect it.