C500: C500 ii: Took lens off while camera still turned on....

seanadl

Active member
Eek.

I just accidentally took the lens off, intending to do a ABB, but forgot to switch the camera off. Only realised the camera was still switched on after I put the cap on the body. I guess the sensor was exposed for maybe 3-4 seconds, but I’m worried I may have done some damage.
 
Every individual whom has used enough cameras in their life has done that at least once. It should be fine if changing aperture on an electronic lens still works as any shortage to the mount is most likely the only concern. (I've seen some people here over the years write that they change non-manual lenses with their cameras still on.)

If you actually exposed the sensor to a lot of light during an ABB then that may be different, IDK.
 
Am I missing something? I change lenses while recording every now and then, especially during events while on tripod. Never harmed my C300
 
I would assume that the biggest risk would be dust due to the charged nature of the sensor ... but still only on the cover layer.

And since the lens focuses light on the sensor it may be less at risk without from a light standpoint ... but the camera is tolerant of overexposure
without damage when the lens is present.

You can burn a Leica shutter ... film M cameras if you leave the lens cap off as the lens focuses the light onto the cloth. Leave that cloth lying
on a table ... or in the sun ... no magnifying glass effect.

All presumption but assume best practice is to shut camera down and change lens in a clean environment if possible or at least point the camera away
from any Harmattan winds ...
 
It is not recommended that you change lenses while the camera is on, but you probably didn't do any damage to the actual sensor. One of the reasons they do not recommend that you remove the lens while it's powered up is because the OLPF in front of the sensor will have a static charge and attract more dirt/dust/debris which isn't good when there is nothing covering it. Also, the electrical contacts that interface with the lens are still powered, so there is a possibility of shorting out something there or in the lens.
 
I remember you could map one of the buttons on the C300 to cut power to the mount for lens changes.
Is there such an option for the C500II?
 
It's a load of crap. You will not harm your camera by changing lenses with the power on. There is zero difference between powered on v powered off state as far as this would effect the sensor. The ONLY difference is that the electrical contacts for the lens mount are active. Canon is the only manufacturer to have ever stated that the camera should be powered down and it's really a load of nonsense.
 
It's a load of crap. You will not harm your camera by changing lenses with the power on. There is zero difference between powered on v powered off state as far as this would effect the sensor. The ONLY difference is that the electrical contacts for the lens mount are active. Canon is the only manufacturer to have ever stated that the camera should be powered down and it's really a load of nonsense.

Good enough for me.
 
I think it was an issue right when the first C300 came out, I remember Phillip Bloom bricking his camera doing that and then Canon fixed it with the firmware grade. I’ve swapped lenses while the cameras on on every body I’ve ever owned and I’ve never had a problem
 
Thanks for the responses. I think, as a rule, i'll turn the camera off before attaching the body cap in future. I don't tend to swap out lenses that often while i'm in studio or running and gunning, so I guess its better to be safe. As it stands, looks like no damage done!
 
Just chiming in as someone who has TWICE bricked their original C300 by changing lenses with the camera on. Due to the electrical contacts in the mount being active, they shorted. First time a fuse in the camera blew and had to be replaced - not very costly. Second time, the whole motherboard was fried, 2000$+ repair at the time. Thankfully insurance covered most of it. Both times the camera was completely dead afterwards, wouldn't turn on.

So even if it's "a load of nonsense" in the sense that is shouldn't happen, it does (or did) happen.

Hopefully that's not a concern with Canon's newer models at all though.
 
Should canons still do this they should be 'rejected as not fit for purpose'.

Under UK law this would happen under the 'sales of good act'

An insrance claim and subsequent insurance hike should not have happened. This is a faulty product.
 
Should canons still do this they should be 'rejected as not fit for purpose'.

Under UK law this would happen under the 'sales of good act'

An insrance claim and subsequent insurance hike should not have happened. This is a faulty product.

Good luck winning that one. They tell you to turn it off when changing lenses.

But maybe they should build some sort of “fool proof” system in that whenever you press in the button to release the lens it automatically kills the contacts and they aren’t powered again until a lens is locked into place.
 
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From a practical point of view a must turn off just doesn’t work as one might have to keep sound or TC running during a lens
Or lose a heap of time on set
 
Yes, there were a very few reports of early C300's shorting out when changing lenses while powered on. It has not been reported since (what was that, like 2012?)

It is extremely unlikely you will do any harm by changing lenses while powered on. I do it every day.
 
From a practical point of view a must turn off just doesn’t work as one might have to keep sound or TC running during a lens
Or lose a heap of time on set

Quantify "heap of time". 10 seconds? 45 seconds? 5 minutes? Any professional camera with TC, that is functioning properly, should not lose TC when turning the camera off.

Maybe I just don't see the big deal. If switching still lenses on a video camera while it's still on and rolling is a necessity, maybe the wrong tools(camera and lenses) are being used in the wrong situation.
 
Just in case any Sony owners are watching this thread, and many people mix brands as A and B cams, in the Sony A7R series cameras the manual specifically states: "Set the power switch of the camera to OFF before you remove the lens." (copied directly from the manual). Obviously the consideration about losing sync will depend on individual circumstances. Overall, if you fry the camera you'd have a hard time claiming against Sony or claiming insurance if they knew about this advice in the manual. Just in case that helps anyone.
 
I always turned any camera off before changing lenses and removing cards.
For me it was the 2nd rule in digital age. 1st one: formatting cards only in camera.
 
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