GONE out of focus WITH THE 5D2 !

Mr.T wrote:
"Chris Malcolm" wrote in message
...
You were the only one to mention "manual flash mode".

"Chris Malcolm" wrote in message
...
Many
cameras have at least one mode of use (such as Manual) in which a
flash trigger firing circuit is available if required, but the camera
doesn't know whether it was used.

I guess the words "mode" and "manual" were meant to mean something else
then, but certainly don't mention anything that would require non standard
equipment. Lets face it, YOU weren't clear, AND *I* already acknowledged
there are circumstances where the camera does not know about non standard
external flash guns and triggers. That wasn't enough for you?

You have NOW cleared that up so why keep beating a dead horse.? If it makes
you feel superior, maybe I have helped you there at least.


The pair of you are mutually reinforcing ambiguity generators.

The PC sync circuit ALWAYS closes. Period. It has no care of modes.
It does not know if a flash is attached or not.

So if one is attached (shoe or PC sync), and on, it will fire. Period.

And the camera won't know it. Period.

--
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"Alan Browne" wrote in message
...
snip


The PC sync circuit ALWAYS closes. Period. It has no care of modes. It
does not know if a flash is attached or not.

So if one is attached (shoe or PC sync), and on, it will fire. Period.

And the camera won't know it. Period.


Respectfully, your last sentence is not exactly true. If there is a flash
attached and turned on, there will be a voltage (quantity and polarity of
which is determined by the flash unit) present across the internal contacts.
And when those PC sync contacts close, there will be a current flow thru
them (quantity & polarity etc...).

So, the camera will "know" it, but in most cases, it has no mechanism to
react to that voltage or current and it won't care.

Ken Hart1 wrote:
"Alan Browne" wrote in message
...
snip

The PC sync circuit ALWAYS closes. Period. It has no care of modes. It
does not know if a flash is attached or not.

So if one is attached (shoe or PC sync), and on, it will fire. Period.

And the camera won't know it. Period.


Respectfully, your last sentence is not exactly true. If there is a flash
attached and turned on, there will be a voltage (quantity and polarity of
which is determined by the flash unit) present across the internal contacts.
And when those PC sync contacts close, there will be a current flow thru
them (quantity & polarity etc...).

So, the camera will "know" it, but in most cases, it has no mechanism to
react to that voltage or current and it won't care.

Happy you wasted the bandwidth?

--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: Remove FreeLunch.
-- usenet posts from gmail.com and googlemail.com are filtered out.

Alan Browne wrote:
Ken Hart1 wrote:
"Alan Browne" wrote in message
...
snip

The PC sync circuit ALWAYS closes. Period. It has no care of modes.
It does not know if a flash is attached or not.

So if one is attached (shoe or PC sync), and on, it will fire. Period.

And the camera won't know it. Period.


Respectfully, your last sentence is not exactly true. If there is a
flash attached and turned on, there will be a voltage (quantity and
polarity of which is determined by the flash unit) present across the
internal contacts. And when those PC sync contacts close, there will
be a current flow thru them (quantity & polarity etc...).

So, the camera will "know" it, but in most cases, it has no mechanism
to react to that voltage or current and it won't care.

Happy you wasted the bandwidth?


Four words: pot, kettle, black, ...period!

Bill Boyce wrote:
Alan Browne wrote:
Ken Hart1 wrote:
"Alan Browne" wrote in message
...
snip

The PC sync circuit ALWAYS closes. Period. It has no care of
modes. It does not know if a flash is attached or not.

So if one is attached (shoe or PC sync), and on, it will fire. Period.

And the camera won't know it. Period.


Respectfully, your last sentence is not exactly true. If there is a
flash attached and turned on, there will be a voltage (quantity and
polarity of which is determined by the flash unit) present across the
internal contacts. And when those PC sync contacts close, there will
be a current flow thru them (quantity & polarity etc...).

So, the camera will "know" it, but in most cases, it has no mechanism
to react to that voltage or current and it won't care.

Happy you wasted the bandwidth?


Four words: pot, kettle, black, ...period!

Hardly. The point was what the camera records in EXIF. It can't record
what it doesn't sense in h/w and f/w.

But I'm glad you got to jeer a little bit, if to no useful effect.

--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: Remove FreeLunch.
-- usenet posts from gmail.com and googlemail.com are filtered out.

Ken Hart1 wrote:
"Alan Browne" wrote in message
...
snip


The PC sync circuit ALWAYS closes. Period. It has no care of
modes. It does not know if a flash is attached or not.

So if one is attached (shoe or PC sync), and on, it will fire.
Period.

And the camera won't know it. Period.


Respectfully, your last sentence is not exactly true. If there is a
flash attached and turned on, there will be a voltage (quantity and
polarity of which is determined by the flash unit) present across
the
internal contacts. And when those PC sync contacts close, there will
be a current flow thru them (quantity & polarity etc...).

So, the camera will "know" it, but in most cases, it has no
mechanism
to react to that voltage or current and it won't care.

Well, actually a digital camera often does have a "mechanism to react
to that voltage". Unfortunately the mechanism is the trigger circuit
and the reaction is that the circuit fries.


--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

In rec.photo.digital Alan Browne wrote:
Mr.T wrote:
"Chris Malcolm" wrote in message
...
You were the only one to mention "manual flash mode".

"Chris Malcolm" wrote in message
...
Many
cameras have at least one mode of use (such as Manual) in which a
flash trigger firing circuit is available if required, but the camera
doesn't know whether it was used.

I guess the words "mode" and "manual" were meant to mean something else
then, --

The phrase used was "Cameras have at least one mode of use (such as
Manual)". I hoped it wouldn't be difficult to realise that I was
likley to be referring to the modes of camera use specified by the
mode dial one which is "Manual".

but certainly don't mention anything that would require non standard
equipment.

There's nothing non-standard about using the PC sync circuit to fire
flashes. It's the oldest standard of flash connection and is still
provided by all cameras which support external flash guns. It's widely
used by people who use multiple remote third party flashes. It's no
more non-standard than using a Nikon or Sigma lens on a Canon camera.

Lets face it, YOU weren't clear, AND *I* already acknowledged
there are circumstances where the camera does not know about non standard
external flash guns and triggers. That wasn't enough for you?

You have NOW cleared that up so why keep beating a dead horse.? If it makes
you feel superior, maybe I have helped you there at least.

The pair of you are mutually reinforcing ambiguity generators.

The PC sync circuit ALWAYS closes. Period. It has no care of modes.
It does not know if a flash is attached or not.

My apologies. I've cearly been guilty of taking advice from people on
the internet who claim that the PC sync circuit is only active in
certain modes, some of whom were apparently experts in using the
facility on my own specific DSLR.

I just went and tested it, and you're quite right, at least in my DSLR
the PC sync circuit is active in all modes, including the special NO
FLASH! mode.

--
Chris Malcolm

In rec.photo.digital Ken Hart1 wrote:

"Alan Browne" wrote in message
...
snip

The PC sync circuit ALWAYS closes. Period. It has no care of modes. It
does not know if a flash is attached or not.

So if one is attached (shoe or PC sync), and on, it will fire. Period.

And the camera won't know it. Period.

Respectfully, your last sentence is not exactly true. If there is a flash
attached and turned on, there will be a voltage (quantity and polarity of
which is determined by the flash unit) present across the internal contacts.
And when those PC sync contacts close, there will be a current flow thru
them (quantity & polarity etc...).

So, the camera will "know" it, but in most cases, it has no mechanism to
react to that voltage or current and it won't care.

That's an improper use of "know". It's like saying someone with a
bisected spinal cord who is paralysed and feels nothing from the waist
down nevertheless "knows" when a pin is stuck in the sole of his
foot. An essential prerequisite to "knowing" something is the
abstraction of a coded signal of the physical event from the site of
the physical event. There is no such circuit attached to a camera's PC
sync circuit.

--
Chris Malcolm