First images of Nikon D600 with 24 MP FX sensor

In rec.photo.digital Floyd L. Davidson wrote:
Chris Malcolm wrote:
In rec.photo.digital Floyd L. Davidson wrote:
Andrew Haley wrote:

The simple fact is that while a sensor is in use it generates a huge
amount of static charge.

And how does it do that? The electronics only use a few volts, which
is hardly much of a static charge when you consider that the sensor

You and Chris Malcom both seem to believe that high voltage is
necessary for a significant static charge; which is not true at
all.

No I didn't think that. I was simply responding to your claim that an
operating sensor collected static as a consequence of being in
operation.

Here is what you said:

"The voltages used in camera sensors are very low, totally
irrelevant to static accumulation."

Now you say you don't think that is true...

No I'm not. If you think I'm contradicting rather than rephrasing
you're misunderstanding.

It has very little to do with operating voltages, and a
great deal to do with how free many electrons are floating
around without a low resistance discharge path *to ground*.

"Floating around" is a bit vague. If you mean floating around in the
air in the form of charged molecules or dust particles I agree with
the proviso that it's not the total number which matters, but the
local concentrations which represent high static charges, because
that's what causes the attraction of dust particles to surfaces.

Exactly. So whether or not the sensor is in operation has nothing to
do with it. Although the operations of focal plane shutter and mirror
box might generate some static which could charge up the sensor
surface -- if it didn't have a charge leakage path.

Whether or not the sensor is in operation has everything to do
with how many free electrons are available with no discharge
path to ground.

But here you seem to consider that the free electrons moving around in
conductive circuits are the same kind of free electrons that in local
concentrations cause the dust attractive phenomena of static
electricity. Note that important word "static". Electricity in
electric circuits isn't static, it's mobile. That's why so much higher
charges and very high voltages are required in electric circuits to
exhibit the phenomena of static electricity, such as dust attraction.

Why would the metal focal plane shutter or the "mirror box"
generate static charge? They have no source of electrons...

No source of electrons?? Where do the electrons come from when you rub
a balloon to charge it up? There are conductive and insulating parts
moving in proximity to one another in both the focal plane shutter and
the mirror box. Don't you remember how the high voltage generators in
your school science lab worked?

And this "charge leakage path" you mention, goes to ground
where?

Ground as in earthed is irrelevant when we're talking about dust
attraction to a camera sensor. What matters are the local
differentials inside the camera. As you (should) know, the static
electrical conditions inside a charged object are completely different
from the outside. All that's required to stop dust attraction to the
camera sensor surface is a leakage path to whatever constitutes
the local electronic circuit ground inside the camera.

A discharge path reduces the charge, but only if it offers a
relatively low resistance to an earth ground.

Static charges are of such high voltage that leakage path resistances
don't have to be "relatively low". They can be very effective while
being surprisingly high in general electrical terms.

I'm sorry, but that is not true. "Low" of course is a relative
term.

They have to be relatively low to allow fast enough discharge to
prevent a build up of charge. Hundreds of thousands of Ohms is
relatively low for most specific applications.

That's what I meant. Hundreds of thousands of ohms is high in
electrical terms, commonplace in electronics, and low with respect to
static charges. It's more than adequately supplied by the tin oxide
coatings on the better camera sensors.

Note that ESD protection devices, such as wrist straps, have
relatively high resistance in order to prevent electrocuting
someone if they come into contract with high voltages while
grounded via the protection device.

Exactly. A nylon string coated with indium tin oxide, or the wet
string I mentioned, would do just fine.

Any conductive
coating sufficient to be as effective as you seem to think these
coatings are would totally block all light!

Do take some time to check the physics. You don't need low resistance
to discharge static. Wet string will do it. Try it for yourself.

*Do* take the time to learn about static electicity!

I don't need to. It's one of the subjects I had to pass exams in when
young, and which I had to keep up to date in order to design
electronics which would survive exposure to occasional high static
charges in the local environment.

For example, open up just about any bit of electronic equipment
with a 5 VDC power supply, and look at how dust collects on the
power supply components!

If you're talking about power supplies which derive their 5V from
mains electricity it's not the 5V which is doing that. If you're
talking about stuff powered only by 5V batteries, then the
accumulation of dirt around the +ve bits isn't dust attracted by
static electrical charges, it's electrochemistry producing substances
which either mimic dirt or hold passing dirt by stickiness derived
from hygroscopic effects.

Not to mention that
a charged camera body is not significantly different than a charged
sensor surface... and unless you are dragging a ground wire, that is
exactly what you have.

You don't seem to have much grounding in the physics of static
electricity.

In fact I have several decades of professional experience.
Given what you've said, it is obvious why you've posted this
sort of bluster...

I notice you say "professional experience" rather than "education". In
other words you've been exposed to the usual superstitions regarding
the oddly counter-intuitive domain of static electrictity common among
engineers who have been told the rules of how to work safely with the
stuff, but haven't an education in it.

A charged camera body would attract dust to the outside
of the camera, not the inside. And inside a highly charged body is a
surprisingly neutral zone, as Tesla was fond of demonstrating to
startled audiences. What's more a camera body carrying a significant
static charge is not going to keep it once you have it in your
hands. And it's not going to acquire such a charge while inside a bag.

Follow the advice you gave above, and get a good education in
static electricity. Avoid trivia contests and displays of the
exotic. Take a few courses in such things as Electro Static
Discharge.

I've got more than enough education in the topic to know that
someone who uses the phrase "Electro Static Discharge" hasn't :-)

--
Chris Malcolm

Chris Malcolm wrote:
In rec.photo.digital Floyd L. Davidson wrote:
Chris Malcolm wrote:
In rec.photo.digital Floyd L. Davidson wrote:
Andrew Haley wrote:

The simple fact is that while a sensor is in use it generates a huge
amount of static charge.

And how does it do that? The electronics only use a few volts, which
is hardly much of a static charge when you consider that the sensor

You and Chris Malcom both seem to believe that high voltage is
necessary for a significant static charge; which is not true at
all.

No I didn't think that. I was simply responding to your claim that an
operating sensor collected static as a consequence of being in
operation.

Here is what you said:

"The voltages used in camera sensors are very low, totally
irrelevant to static accumulation."

Now you say you don't think that is true...

No I'm not. If you think I'm contradicting rather than rephrasing
you're misunderstanding.

We can all read Chris, it's pretty obvious what you said.

It also happens to be absolutely wrong.

It has very little to do with operating voltages, and a
great deal to do with how free many electrons are floating
around without a low resistance discharge path *to ground*.

"Floating around" is a bit vague. If you mean floating around in the
air in the form of charged molecules or dust particles I agree with
the proviso that it's not the total number which matters, but the
local concentrations which represent high static charges, because
that's what causes the attraction of dust particles to surfaces.

No, not "in the air". Free electrons on the surface of the sensor,
and anything to which it is electrically connected. That could, for
example, mean the entire inside of the mirror box is charged in relation
to any dust particle that finds its way in. Once the dust particle
is anywhere close it will be attracted to the object with the highest
charge. Generally that is going to be something most close to the source
of the charge... in this case the sensor itself.

Exactly. So whether or not the sensor is in operation has nothing to
do with it. Although the operations of focal plane shutter and mirror
box might generate some static which could charge up the sensor
surface -- if it didn't have a charge leakage path.

Whether or not the sensor is in operation has everything to do
with how many free electrons are available with no discharge
path to ground.

But here you seem to consider that the free electrons moving around in
conductive circuits are the same kind of free electrons that in local
concentrations cause the dust attractive phenomena of static
electricity.

In fact they are the same electrons, and have the same charge.

ote that important word "static". Electricity in
electric circuits isn't static, it's mobile. That's why so much higher
charges and very high voltages are required in electric circuits to
exhibit the phenomena of static electricity, such as dust attraction.

BS.

As I previously suggested, just look inside almost any 5 VDC power supply
that has been operating for a few months or years, and see where the
dust build up is.

Why would the metal focal plane shutter or the "mirror box"
generate static charge? They have no source of electrons...

No source of electrons?? Where do the electrons come from when you rub
a balloon to charge it up? There are conductive and insulating parts
moving in proximity to one another in both the focal plane shutter and
the mirror box. Don't you remember how the high voltage generators in
your school science lab worked?

"Conductive and insulating parts"? Wrong. Go back to your
school lab... (Incidentally, I used to maintain a rather large
Van De Graph particle accelerator, and a medium sized electron
accelerator.)

The shutter is a metal conductor, so is virtually the entire
mirror mechanism, and of course it is all encased in metal.
There is nothing like the source of electrons available from
normal operation of the sensor. (Keep in mind these devices are
all based on something known as a Charge Coupled Device.)

And this "charge leakage path" you mention, goes to ground
where?

Ground as in earthed is irrelevant when we're talking about dust
attraction to a camera sensor. What matters are the local
differentials inside the camera. As you (should) know,

Wrong again. What matters is the difference between the local
parts of the camera as opposed to the dust particle. Clearly
the entire camera is going to have a significant charge if it 1)
generates a charge, which it does, and 2) if it is not bled off
to ground, which it isn't. The question is which part of the
camera will have a higher potential, and thus attract more dust.

Take a look inside of any 5 volt power supply to get your
answer.

the static
electrical conditions inside a charged object are completely different
from the outside. All that's required to stop dust attraction to the
camera sensor surface is a leakage path to whatever constitutes
the local electronic circuit ground inside the camera.

Note that on any typical 5 VDC power supply the entire unit is
encased in a metal shield, it is also probably well grounded
too. Yet there are some very obvious places where more dust
collects. And it clearly shows that what you've said is
absolutely not true.

A discharge path reduces the charge, but only if it offers a
relatively low resistance to an earth ground.

Static charges are of such high voltage that leakage path resistances
don't have to be "relatively low". They can be very effective while
being surprisingly high in general electrical terms.

I'm sorry, but that is not true. "Low" of course is a relative
term.

They have to be relatively low to allow fast enough discharge to
prevent a build up of charge. Hundreds of thousands of Ohms is
relatively low for most specific applications.

That's what I meant. Hundreds of thousands of ohms is high in
electrical terms, commonplace in electronics, and low with respect to
static charges. It's more than adequately supplied by the tin oxide
coatings on the better camera sensors.

Note that ESD protection devices, such as wrist straps, have
relatively high resistance in order to prevent electrocuting
someone if they come into contract with high voltages while
grounded via the protection device.

Exactly. A nylon string coated with indium tin oxide, or the wet
string I mentioned, would do just fine.

But that wrist strap will not prevent attraction of dust!

Any conductive
coating sufficient to be as effective as you seem to think these
coatings are would totally block all light!

Do take some time to check the physics. You don't need low resistance
to discharge static. Wet string will do it. Try it for yourself.

*Do* take the time to learn about static electicity!

I don't need to. It's one of the subjects I had to pass exams in when
young, and which I had to keep up to date in order to design
electronics which would survive exposure to occasional high static
charges in the local environment.

I'm sure you learned how to pass a test... But you don't seem to
have understood the subject as well as the test.

For example, open up just about any bit of electronic equipment
with a 5 VDC power supply, and look at how dust collects on the
power supply components!

If you're talking about power supplies which derive their 5V from
mains electricity it's not the 5V which is doing that.

Stop making silly statements. *LOOK* at a real live power supply.

If you're
talking about stuff powered only by 5V batteries, then the
accumulation of dirt around the +ve bits isn't dust attracted by
static electrical charges, it's electrochemistry producing substances
which either mimic dirt or hold passing dirt by stickiness derived
from hygroscopic effects.

Not to mention that
a charged camera body is not significantly different than a charged
sensor surface... and unless you are dragging a ground wire, that is
exactly what you have.

You don't seem to have much grounding in the physics of static
electricity.

In fact I have several decades of professional experience.
Given what you've said, it is obvious why you've posted this
sort of bluster...

I notice you say "professional experience" rather than "education". In

Yep. Not academic (though of course I've had a bit of that too)
so much as real hands on experience.

other words you've been exposed to the usual superstitions regarding
the oddly counter-intuitive domain of static electrictity common among
engineers who have been told the rules of how to work safely with the
stuff, but haven't an education in it.

If you can't support your foolishness with facts and have to
resort to more bluster and additional gratuitous personal
insults, it does suggest maybe you are projecting a bit much!

A charged camera body would attract dust to the outside
of the camera, not the inside. And inside a highly charged body is a
surprisingly neutral zone, as Tesla was fond of demonstrating to
startled audiences. What's more a camera body carrying a significant
static charge is not going to keep it once you have it in your
hands. And it's not going to acquire such a charge while inside a bag.

Follow the advice you gave above, and get a good education in
static electricity. Avoid trivia contests and displays of the
exotic. Take a few courses in such things as Electro Static
Discharge.

I've got more than enough education in the topic to know that
someone who uses the phrase "Electro Static Discharge" hasn't :-)

Really! Cute.

(Try entering that into a Google search.)

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)

"Chris Malcolm" wrote in message
...
I've got more than enough education in the topic to know that
someone who uses the phrase "Electro Static Discharge" hasn't :-)

Yes :-) however the term is so common it is more often referred to as ESD.

Trevor.

"Trevor" wrote:
"Chris Malcolm" wrote:
I've got more than enough education in the topic to know that
someone who uses the phrase "Electro Static Discharge" hasn't :-)

Yes :-) however the term is so common it is more often referred to as ESD.

So instead of saying what you did, this would be more appropriate:

Bull**** :-) The term is well defined and in common use by
virtually everyone who has sufficient academic background.

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)

"Floyd L. Davidson" wrote in message
...
"Trevor" wrote:
"Chris Malcolm" wrote:
I've got more than enough education in the topic to know that
someone who uses the phrase "Electro Static Discharge" hasn't :-)

Yes :-) however the term is so common it is more often referred to as ESD.

So instead of saying what you did, this would be more appropriate:

Bull**** :-) The term is well defined and in common use by
virtually everyone who has sufficient academic background.

Either works IMO :-)

Trevor.

In rec.photo.digital Floyd L. Davidson wrote:
"Trevor" wrote:
"Chris Malcolm" wrote:
I've got more than enough education in the topic to know that
someone who uses the phrase "Electro Static Discharge" hasn't :-)

Yes :-) however the term is so common it is more often referred to as ESD.

So instead of saying what you did, this would be more appropriate:

Bull**** :-) The term is well defined and in common use by
virtually everyone who has sufficient academic background.

It's a common error. So common that when you try googling it google
substitutes the correct term -- electrostatic. There's no such thing
as a textbook with "Electro Static" in the title. I think being
acquainted with one at least one single textbook is a necessary
minimum sufficiency for "academic background" :-)

--
Chris Malcolm

Chris Malcolm wrote:
In rec.photo.digital Floyd L. Davidson wrote:
"Trevor" wrote:
"Chris Malcolm" wrote:
I've got more than enough education in the topic to know that
someone who uses the phrase "Electro Static Discharge" hasn't :-)

Yes :-) however the term is so common it is more often referred to as ESD.

So instead of saying what you did, this would be more appropriate:

Bull**** :-) The term is well defined and in common use by
virtually everyone who has sufficient academic background.

It's a common error. So common that when you try googling it google
substitutes the correct term -- electrostatic. There's no such thing
as a textbook with "Electro Static" in the title. I think being
acquainted with one at least one single textbook is a necessary
minimum sufficiency for "academic background" :-)

So... Chris Malcolm stoops to an idiotic *SPELLING FLAME.*

That is just hillarious! (And wrong too, but...)

I suppose you think spelling is significant because clearly you
have little understanding of the functionality of static
electricity.

You worry about spelling, but say things like these choice
quotes from your articles in this thread. I politely called you
on half of these, but didn't mention the fact that each of these
statements is a clear indication that you have no business
discussing this as a technical topic.

----
"A charged camera body would attract dust to the outside
of the camera, not the inside."
----

----
" "The voltages used in camera sensors are very low, totally
irrelevant to static accumulation."

Now you say you don't think that is true...

No I'm not. If you think I'm contradicting rather than rephrasing
you're misunderstanding."
----

----
"Electricity in electric circuits isn't static, it's
mobile. That's why so much higher charges and very high voltages
are required in electric circuits to exhibit the phenomena of
static electricity, such as dust attraction."
----

----
"There are conductive and insulating parts moving in proximity
to one another in both the focal plane shutter and the mirror
box. Don't you remember how the high voltage generators in your
school science lab worked??
----


Maybe if you had ever actually worked with this, as opposed to
just reading text books, some of what the text books say would
have stuck with you a little better.

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)

tony cooper wrote:
On Mon, 25 Jun 2012 07:28:50 -0800, (Floyd L.
Davidson) wrote:

Chris Malcolm wrote:
In rec.photo.digital Floyd L. Davidson wrote:
"Trevor" wrote:
"Chris Malcolm" wrote:
I've got more than enough education in the topic to know that
someone who uses the phrase "Electro Static Discharge" hasn't :-)

Yes :-) however the term is so common it is more often referred to as ESD.

So instead of saying what you did, this would be more appropriate:

Bull**** :-) The term is well defined and in common use by
virtually everyone who has sufficient academic background.

It's a common error. So common that when you try googling it google
substitutes the correct term -- electrostatic. There's no such thing
as a textbook with "Electro Static" in the title. I think being
acquainted with one at least one single textbook is a necessary
minimum sufficiency for "academic background" :-)

So... Chris Malcolm stoops to an idiotic *SPELLING FLAME.*

When you bring up "sufficient academic background", you leave yourself
open to comments about your spelling and grammar. English composition
is an academic subject.

Chris is the idiot who brought it up.

But regardless of that, this is Usenet and spelling flames are too stoopid
to bothr wit.

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)

tony cooper wrote:
On Mon, 25 Jun 2012 07:57:38 -0800, (Floyd L.
Davidson) wrote:

tony cooper wrote:
On Mon, 25 Jun 2012 07:28:50 -0800, (Floyd L.
Davidson) wrote:

Chris Malcolm wrote:
In rec.photo.digital Floyd L. Davidson wrote:
"Trevor" wrote:
"Chris Malcolm" wrote:
I've got more than enough education in the topic to know that
someone who uses the phrase "Electro Static Discharge" hasn't :-)

Yes :-) however the term is so common it is more often referred to as ESD.

So instead of saying what you did, this would be more appropriate:

Bull**** :-) The term is well defined and in common use by
virtually everyone who has sufficient academic background.

It's a common error. So common that when you try googling it google
substitutes the correct term -- electrostatic. There's no such thing
as a textbook with "Electro Static" in the title. I think being
acquainted with one at least one single textbook is a necessary
minimum sufficiency for "academic background" :-)

So... Chris Malcolm stoops to an idiotic *SPELLING FLAME.*

When you bring up "sufficient academic background", you leave yourself
open to comments about your spelling and grammar. English composition
is an academic subject.

Chris is the idiot who brought it up.

But regardless of that, this is Usenet and spelling flames are too stoopid
to bothr wit.

Depends. Different things annoy different people. I find many of
your arguments too stupid and petty to argue with even if there are no
misspelled words.

Given your logic in the above instance, I would hope so!

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)

"Chris Malcolm" wrote in message
...
In rec.photo.digital Floyd L. Davidson wrote:
"Trevor" wrote:
"Chris Malcolm" wrote:
I've got more than enough education in the topic to know that
someone who uses the phrase "Electro Static Discharge" hasn't :-)

Yes :-) however the term is so common it is more often referred to as
ESD.

So instead of saying what you did, this would be more appropriate:

Bull**** :-) The term is well defined and in common use by
virtually everyone who has sufficient academic background.

It's a common error. So common that when you try googling it google
substitutes the correct term -- electrostatic. There's no such thing
as a textbook with "Electro Static" in the title. I think being
acquainted with one at least one single textbook is a necessary
minimum sufficiency for "academic background" :-)


And knowing English is a flexible, evolving language should be too. Either
is acceptable. Here's what Wikipedia has to say about *ESD*.
http://en.wikipedia.org/wiki/Electrostatic_discharge
It is not called ED for a reason, that is more commonly connected with mens
complaints you may be well aware of :-)

Trevor.