Necessary to Off Your Camera?

[ttw]

When changing lens?

[AJ23]

Film: not necessary but good practice
Digital: good practice but not necessary

[AJ23]

Just to reiterate what I've said. For digital bodies, when the camera is still on, the sensor might be charged, and thus when you change lenses, there is a chance that dust/dirt might get stuck onto it.

So if the camera is off, the chance of dust/dirt sticking on the sensor is lessen, though not totally eliminated.

As for film, switching it on/off during lense change is a matter of preference.

[blurblock]

DSLR, preferable so, especially if your previous lens has higher lower f-stop, for example f/4 switch to f/2.8. If you did not switch off, they will still take f/4 as your shooting f/stop .

[mervlam]

Originally Posted by AJ23 Just to reiterate what I've said. For digital bodies, when the camera is still on, the sensor might be charged, and thus when you change lenses, there is a chance that dust/dirt might get stuck onto it. So if the camera is off, the chance of dust/dirt sticking on the sensor is lessen, though not totally eliminated. As for film, switching it on/off during lense change is a matter of preference.

the sensor can still remain charged for a short while even when the power is off.

[espn]

Normally I don't, for film or digital, even changing CF I also dun turn it off, however, do take note of the f-stop as mentioned by blurblock, I've switch a f/3.5 lense to f/1.8 and totally forget about the f-stop.

[ST1100]

Normally, i don't turn the camera off except to test the on-off switch. It's left 'on' when i:

- change lenses (and i shoot primes, so i change lenses plenty);
- change CF card
- change battery.

The only other time i would turn it off is to save power for long periods when it might be accidentally turned on, like 3 days in the field w/o power source.

i don't think there's any proof to the theory that a charged sensor attracts more dust when changing lenses. If there is dust BEHIND the shutter, it will stick to the sensor (if the theory holds) whether or not you're changing lenses. And dust gets introduced into the mirror chamber when you change lenses; it does not get behind the shutter (yet). It will, when you fire, it will get behind the shutter, and by then the sensor is fully charged, and the lens is already mounted.

[Kho King]

According to what Nikon suggested, u should off your camera before taking off a lens, this is to avoid contact short. When u mount a lens on, the camera is talking to the lens, ur sudden disconnection might do harm to the lens/camera.

I remember reading this in Nikon manual (for my F60 camera?).

[Shadus]

my understanding is tht a charged CMOS sensor does not attact more dust than a fully discharged CMOS sensor. a charged CCD sensors does attract dust. since we're in a canon segment of the forum. and we're toking about DSLR, I would guess its a CMOS sensor.

[ttw]

Originally Posted by Shadus my understanding is tht a charged CMOS sensor does not attact more dust than a fully discharged CMOS sensor. a charged CCD sensors does attract dust. since we're in a canon segment of the forum. and we're toking about DSLR, I would guess its a CMOS sensor.

Thanks for all the response

My primary concern is whether it will be harmful to the camera (or lens)
And I also read that when you use IS lens, you should off the IS when you take it off. Anybody knows why?

[AJ23]

Like I said in the original post, it's always good practice but not a necessity.

[sehsuan]

Originally Posted by ttw Thanks for all the response My primary concern is whether it will be harmful to the camera (or lens) And I also read that when you use IS lens, you should off the IS when you take it off. Anybody knows why?

yes. because if the IS group is still active (not locked), it may get knocks while it remain unlocked and damage it.

[silver.wolf]

so has anyone damaged their equipments before while changing lenses without powering off your camera?

[KNIGHT ONG]

Good practice to off your camera when changing lens.

Also off your lens VR mode if the lens has this function during changing or not in use.

[zekai]

good practise

[lhfoo]

not necessarily .... never even have my 300D off even when changing CF.

[mama]

Is a good practise to turn it off especially you are inserting anything with electro contact, especially the Lens with twisted mounting contacting from left to right or right to left. Nothing happen now, doesnt mean it will not happen. Best switch off, safer, is your assets, you can decide what you want to do to it.

[HelmetBox]

I take so long to change my lenses that the body just powers off automatically

[Shadus]

dun need change lens, get a 24-300

[lhfoo]

Originally Posted by Shadus dun need change lens, get a 24-300

Better get 17-600mm/f2.0 ....