Switching lenses without turning off camera?

Ira · 05-21-2010, 04:24 PM

If anyone wants me to email them my ESD piece that I did for the Florida's Turnpike....an easy to read 16-page study and lesson on the subject...PM me.

There is no way in helll you should have a unit powered up, and introduce an ESD event by handling a lens made of plastic. And plastic is the biggest conductor, worst material for tribo-electric charging, the biggest cause of ESD damage.

ESD is the major cause of damage/faulty operation of all bad cards.

distudio · 05-21-2010, 08:59 PM

Originally posted by Ira

If anyone wants me to email them my ESD piece that I did for the Florida's Turnpike....an easy to read 16-page study and lesson on the subject...PM me.

There is no way in helll you should have a unit powered up, and introduce an ESD event by handling a lens made of plastic. And plastic is the biggest conductor, worst material for tribo-electric charging, the biggest cause of ESD damage.

ESD is the major cause of damage/faulty operation of all bad cards.

ESD affects electrostatic sensitive components whether they are energised or not, most importantly they are generally most vulnerable out of circuit. A well designed circuit, such as one that has exposed contacts should have integrated ESD protection, it's all pretty basic from a design perspective.

The concept that the charge on the sensor due to it being powered would attract dust has been well and truly debunked many times. The voltages concerned are not remotely dust attractive, there may be a latent static charge on some polymer surfaces of the sensor due to a mechanical action (such as brushing with an brush that's not ESD safe) but in any case powering off the unit will not cause this type of static charge to dissipate.

For what it's worth I've never bothered to turn off any of my camera bodies (MZ-5n, MZ-S, *ist D, K10D, K20D, K-x) whilst changing lenses and I've never encountered a problem. However I don't own any SDM or power zoom lenses and if I did then I might tend to be more cautious as I the whole system seems to be a pretty poor implementation.

BillM · 05-22-2010, 05:30 AM

How come pentax has no interlock between lens release button
and power supply?

Ira · 05-22-2010, 07:27 AM

Originally posted by distudio

ESD affects electrostatic sensitive components whether they are energised or not.

Yes, but they are made additionally sensitive by being powered.

Also, there's a misconception that ESD immediately damages a component, which it does. But the majority of ESD damage results in a shortening of the component's life--it's not usually immediate.

Would anyone like to discuss the familiar metallic ESD bag? And how everyone uses it incorrectly?

distudio · 05-22-2010, 07:49 AM

Originally posted by Ira

Yes, but they are made additionally sensitive by being powered.

Also, there's a misconception that ESD immediately damages a component, which it does. But the majority of ESD damage results in a shortening of the component's life--it's not usually immediate.

Would anyone like to discuss the familiar metallic ESD bag? And how everyone uses it incorrectly?

The point is that the warning not to have the camera powered on whilst changing lenses has nil to do with ESD or static build-up around the sensor assembly, it's about potential shortcomings in the connection system. The contacts being proud and vulnerable to potential ESD should be sufficiently protected, what's baffling (as someone else mentioned) is why there is no interlock system associated with the lens release which negates the potential of damage during lens removal/replacement.

Class A · 05-23-2010, 07:41 PM

Originally posted by Ira

Would anyone like to discuss the familiar metallic ESD bag? And how everyone uses it incorrectly?

How are they used incorrectly?

alohadave · 05-23-2010, 08:24 PM

Originally posted by BillM

How come pentax has no interlock between lens release button
and power supply?

Because it's not needed.

BillM · 05-25-2010, 09:59 AM

Quote:

"Because it's not needed"

when a heavy inductive load is powered down, say app is ignition coil
in automobile or a SDM drive in lens, field collapes, "BIG EMF" happens
is exploited in auto, is destructive in lens if engineering falls short in
dealing with it. Among conditions that occur can be arching conditions
that degrade contacts, thats nothing compared to what could happen
to field windings of SDM motor if insulation is over-voltaged.
A little preventative insurance could go a long way.

rkt · 05-25-2010, 10:32 AM

never tried changing lenses, or flash, when powered on... I think there is a good risk of a short-circuit/static of some type, that could fry some part of the electronics ...

alohadave · 05-25-2010, 12:53 PM

Originally posted by BillM

when a heavy inductive load is powered down, say app is ignition coil
in automobile or a SDM drive in lens, field collapes, "BIG EMF" happens
is exploited in auto, is destructive in lens if engineering falls short in
dealing with it. Among conditions that occur can be arching conditions
that degrade contacts, thats nothing compared to what could happen
to field windings of SDM motor if insulation is over-voltaged.
A little preventative insurance could go a long way.

Right, and how many cameras do you know that use car batteries for power.

We are talking about 3-5 volts and milliamps. Not dangerous stuff. I think that the engineers would design the system to work powered on, or you'd be hearing about massive amounts of damaged lenses from everyone. Canon has been making USM lenses for 20 years and I haven't heard of a single instance of a lens being damaged by this 'BIG EMF'.

Comparing an ignition coil to an SDM motor is a bit ridiculous.

r0ckstarr · 05-25-2010, 09:08 PM

I accidentally swapped lenses without powering off the camera first. Didn't realize that I had done it until I went to turn the camera on and noticed that it was already on. Nothing bad happened.

kalison · 05-25-2010, 09:18 PM

I used to switch my Canon lenses all the time without powering them down. Never had an issue. Because of this habit, I have been doing the same with my K7 and really didnt think it would be any different.

dlacouture · 05-26-2010, 01:08 AM

Well, I once swapped lenses with my K20 still powered on (I usually power it off while swapping), and it just got unresponsive then...
In the end I had to remove the battery...

So, now I always make sure I power the camera down before swapping the lenses (easy to do : I switch it off with my index, and I unlock the lens with my ring finger, it became a natural combo).

simico · 05-26-2010, 02:31 AM

Originally posted by BillM

How come pentax has no interlock between lens release button
and power supply?

Just curious: how do you know it doesn't have?

cosmicap · 05-26-2010, 03:08 AM

I had never given it much thought but from now I will make certain to avoid it being "on". Not worth the risk. For me not easy to repair or replace, besides that, I like to look after my gear. It's good gear.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Turning Camera On With No Lens Attached	Ramomar	Troubleshooting and Beginner Help	5	08-12-2009 01:41 PM
Switching!	snkenai	Welcomes and Introductions	6	03-12-2009 02:02 PM
Lenses, lenses, and more lenses, a camera (or 2) and a camera bag?	krs	Pentax SLR Lens Discussion	11	01-04-2009 04:11 PM
On the turning away	axl	Post Your Photos!	17	11-12-2008 02:12 PM
I'm Switching!	davebris33	General Talk	17	08-29-2008 05:58 AM

05-21-2010, 04:24 PM	#31
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	If anyone wants me to email them my ESD piece that I did for the Florida's Turnpike....an easy to read 16-page study and lesson on the subject...PM me. There is no way in helll you should have a unit powered up, and introduce an ESD event by handling a lens made of plastic. And plastic is the biggest conductor, worst material for tribo-electric charging, the biggest cause of ESD damage. ESD is the major cause of damage/faulty operation of all bad cards.

05-21-2010, 08:59 PM	#32
distudio Veteran Member Join Date: Jul 2007 Location: Sydney Photos: Albums Posts: 450	Originally posted by Ira If anyone wants me to email them my ESD piece that I did for the Florida's Turnpike....an easy to read 16-page study and lesson on the subject...PM me. There is no way in helll you should have a unit powered up, and introduce an ESD event by handling a lens made of plastic. And plastic is the biggest conductor, worst material for tribo-electric charging, the biggest cause of ESD damage. ESD is the major cause of damage/faulty operation of all bad cards. ESD affects electrostatic sensitive components whether they are energised or not, most importantly they are generally most vulnerable out of circuit. A well designed circuit, such as one that has exposed contacts should have integrated ESD protection, it's all pretty basic from a design perspective. The concept that the charge on the sensor due to it being powered would attract dust has been well and truly debunked many times. The voltages concerned are not remotely dust attractive, there may be a latent static charge on some polymer surfaces of the sensor due to a mechanical action (such as brushing with an brush that's not ESD safe) but in any case powering off the unit will not cause this type of static charge to dissipate. For what it's worth I've never bothered to turn off any of my camera bodies (MZ-5n, MZ-S, *ist D, K10D, K20D, K-x) whilst changing lenses and I've never encountered a problem. However I don't own any SDM or power zoom lenses and if I did then I might tend to be more cautious as I the whole system seems to be a pretty poor implementation.

05-22-2010, 05:30 AM	#33
BillM Veteran Member Join Date: Jan 2010 Location: Ferguson, Mo. Photos: Gallery Posts: 1,348	How come pentax has no interlock between lens release button and power supply?

05-22-2010, 07:27 AM	#34
Ira Inactive Account Join Date: Mar 2009 Location: Coral Springs, FL Photos: Gallery \| Albums Posts: 5,216	Originally posted by distudio ESD affects electrostatic sensitive components whether they are energised or not. Yes, but they are made additionally sensitive by being powered. Also, there's a misconception that ESD immediately damages a component, which it does. But the majority of ESD damage results in a shortening of the component's life--it's not usually immediate. Would anyone like to discuss the familiar metallic ESD bag? And how everyone uses it incorrectly?

05-22-2010, 07:49 AM	#35
distudio Veteran Member Join Date: Jul 2007 Location: Sydney Photos: Albums Posts: 450	Originally posted by Ira Yes, but they are made additionally sensitive by being powered. Also, there's a misconception that ESD immediately damages a component, which it does. But the majority of ESD damage results in a shortening of the component's life--it's not usually immediate. Would anyone like to discuss the familiar metallic ESD bag? And how everyone uses it incorrectly? The point is that the warning not to have the camera powered on whilst changing lenses has nil to do with ESD or static build-up around the sensor assembly, it's about potential shortcomings in the connection system. The contacts being proud and vulnerable to potential ESD should be sufficiently protected, what's baffling (as someone else mentioned) is why there is no interlock system associated with the lens release which negates the potential of damage during lens removal/replacement.

05-23-2010, 07:41 PM	#36
Class A Pentaxian Join Date: Aug 2008 Location: Wellington, New Zealand Posts: 11,251	Originally posted by Ira Would anyone like to discuss the familiar metallic ESD bag? And how everyone uses it incorrectly? How are they used incorrectly?

05-23-2010, 08:24 PM	#37
alohadave Veteran Member Join Date: Jan 2008 Location: Quincy, MA Photos: Gallery \| Albums Posts: 2,024	Originally posted by BillM How come pentax has no interlock between lens release button and power supply? Because it's not needed.

05-25-2010, 09:59 AM	#38
BillM Veteran Member Join Date: Jan 2010 Location: Ferguson, Mo. Photos: Gallery Posts: 1,348	Quote: "Because it's not needed" when a heavy inductive load is powered down, say app is ignition coil in automobile or a SDM drive in lens, field collapes, "BIG EMF" happens is exploited in auto, is destructive in lens if engineering falls short in dealing with it. Among conditions that occur can be arching conditions that degrade contacts, thats nothing compared to what could happen to field windings of SDM motor if insulation is over-voltaged. A little preventative insurance could go a long way.

05-25-2010, 10:32 AM	#39
rkt Senior Member Join Date: Oct 2009 Location: Germany Posts: 154	never tried changing lenses, or flash, when powered on... I think there is a good risk of a short-circuit/static of some type, that could fry some part of the electronics ...

05-25-2010, 12:53 PM	#40
alohadave Veteran Member Join Date: Jan 2008 Location: Quincy, MA Photos: Gallery \| Albums Posts: 2,024	Originally posted by BillM when a heavy inductive load is powered down, say app is ignition coil in automobile or a SDM drive in lens, field collapes, "BIG EMF" happens is exploited in auto, is destructive in lens if engineering falls short in dealing with it. Among conditions that occur can be arching conditions that degrade contacts, thats nothing compared to what could happen to field windings of SDM motor if insulation is over-voltaged. A little preventative insurance could go a long way. Right, and how many cameras do you know that use car batteries for power. We are talking about 3-5 volts and milliamps. Not dangerous stuff. I think that the engineers would design the system to work powered on, or you'd be hearing about massive amounts of damaged lenses from everyone. Canon has been making USM lenses for 20 years and I haven't heard of a single instance of a lens being damaged by this 'BIG EMF'. Comparing an ignition coil to an SDM motor is a bit ridiculous.

Thread Tools	Search this Thread
	Search this Thread: Advanced Search

05-25-2010, 09:08 PM	#41
r0ckstarr Veteran Member Join Date: Sep 2009 Location: Texas Photos: Gallery Posts: 3,507	I accidentally swapped lenses without powering off the camera first. Didn't realize that I had done it until I went to turn the camera on and noticed that it was already on. Nothing bad happened.

05-25-2010, 09:18 PM	#42
kalison Veteran Member Join Date: May 2010 Location: Utah Posts: 376	I used to switch my Canon lenses all the time without powering them down. Never had an issue. Because of this habit, I have been doing the same with my K7 and really didnt think it would be any different.

05-26-2010, 01:08 AM	#43
dlacouture Veteran Member Join Date: Jul 2008 Location: Var, South of France Photos: Albums Posts: 1,074	Well, I once swapped lenses with my K20 still powered on (I usually power it off while swapping), and it just got unresponsive then... In the end I had to remove the battery... So, now I always make sure I power the camera down before swapping the lenses (easy to do : I switch it off with my index, and I unlock the lens with my ring finger, it became a natural combo).

05-26-2010, 02:31 AM	#44
simico Veteran Member Join Date: Jan 2009 Location: Budapest Posts: 821	Originally posted by BillM How come pentax has no interlock between lens release button and power supply? Just curious: how do you know it doesn't have?

05-26-2010, 03:08 AM	#45
cosmicap Senior Member Join Date: Oct 2008 Location: Horsham, VIC, Australia Photos: Albums Posts: 108	I had never given it much thought but from now I will make certain to avoid it being "on". Not worth the risk. For me not easy to repair or replace, besides that, I like to look after my gear. It's good gear.