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Old Nov 13, 2004, 3:55 PM   #11
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Canon USA has always insisted that their camera max limit is 6V. We all knew their position already 3 years ago... You should be all set then, nothing further should be of interest to you
Allow me to decide what is interesting to me, not you. For instance, the above quote of yours is interesting (and, as usual, condescending), given this next comment of yours dated 10/4/04:

Quote:
Where does Canon says 6V (can someone find it)?
I thought you knew it for 3 years??? Seems contradictory.

Look - NHL, I mean you no personal disrespect, and I partly blame myself for posting this question in here, knowing you would probably jump in and be condescending and sarcastic with your replies to me and others (mission accomplished). My purpose was/is to get the facts, due to my own camera malfunction and to an apparently unanswered question about the potential for damage. When I saw this info from Westphal and in the Canon e-mail to me, I thought it would be of use. I foolishly tried for a factual thread, but I seem to bring out the need in you for ridicule, sarcasm and condescension. I will pursue my questions on other photo boards and forums where the adults speak openly, but respectfully to one another. We've been through this before and I've always left the thread to avoid silly name-calling arguments with you.

For the sake of peace and to allow the others here to avoid seeing these diatribes, I will do so again and go one step further. I will no longer address you or your posts in these forums. I will ask you not to address me in the same manner (you may assume any post I make has nothing whatever to do with you, implied or directly). Let's just leave each other alone and all should be fine. How you deal with the others you insult, ridicule or condescend to, is between you and them.

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Old Nov 14, 2004, 9:07 AM   #12
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flint350

I mean you no personal disrespect - and for that I'm sorry (and to others). Like you I just wanted to keep the facts straight. So far theses are the facts:

1. Your camera is in the shop and not my, but according to the statistics that you have first incited it should have been 200% dead all over.

2. Canon is an ISO-9000/1 company, and no "canned" e-mail from any sale office can change their certification.

3. I have avoided 'name-calling' anyone in all my posts. I only tried to keep the facts straight... There's already lots of misinformation being spread around the internet, and I will not hesitate to correct it again!

I've tried to remain open here and have an adult conversation - You refused to accept there's a possibilty that the camera is indeed designed to the international standard in Japan: The ISO-10330 is only one of the Work Items (WIs) there's dozen more such as timings, synchronization, shutter speed, and even white balance that other ISO documents called out as well so that all theses instruments can meet to interoperate with one another
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Old Nov 14, 2004, 9:08 PM   #13
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I did a small experiment today with my 10D, and hopefully can put this whole issue to bed once and for all. Anyone with a basic skill in electronic can repeat this test: All you need is an adjustable power supply with a current limit that can be fixed. The ISO-10330 calls for 30mA max for a typical strobe, but you don't need to set it this high (minimizing the risk of damaging the camera). Also the electronic switch in the sync terminal is open when the shutter is closed so there'll be no current flow at this time!

Slowly raise this voltage until it can't increase anymore, this is the onset of the protection circuit kicking in (and when the current started to flow). Now I know (Metz knew) what this camera's limit is, exceeding the ISO standard by a wide margin. PM me if anyone wants to compare notes, but this leads me to only one conclusion: someone at Canon USA is ultra conservative (either that or their left arm did not talk to their right)!

The reason I did this experiment was I expected my 10D to clamp the Metz 45CT-5 output at 24V, but it did not since the camera's protection was set higher:





Someone at Canon did their homework and they deserve an A+ in my book

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Old Nov 15, 2004, 8:46 AM   #14
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NHL, are your PC connector and hotshoe center pin electrically connected?
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Old Nov 15, 2004, 11:03 AM   #15
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KCan wrote:
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NHL, are your PC connector and hotshoe center pin electrically connected?
Not on the 10D, at least they don't ohm out (hint of redundancy here...)
However according to the ISO-10330, they are spec'ed identically and tested (with the same set-up) no differently from one another.

Is your email still the same? 8)
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Old Nov 15, 2004, 12:27 PM   #16
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NHL wrote:
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Is your email still the same? 8)
Yes NHL
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Old Dec 29, 2004, 9:07 PM   #17
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Sorry to chime in late.
Just to add my 2 cents in.
I haven't read the ISO spec. just what has been said here.
First is the test spec 24V @ 100mA a max, min or nominal test spec?
Second if the spec doesn't specify where the test is to be taken (across the Hot Shoe or the sync terminal)
So if the test is conducted over one of these and it passes, it passes. The other connect point can fail and the camera would still pass.

If the test spec is 24V @ 100mA and that's a max spec then the test can be run at a lower voltage. The camera passed at a voltage lower than specified so it would be a good test and a 6V (Canon) or 12V (Nikon) would be good. If the camera passes the ISO spec they don't have to tell us what they acheived their spec at. It passed the ISO spec that's all that matters the camera maker.

Also Nikon is stating a lower voltage than the ISO spec.

That would lead me to think the test spec is worded 24V @100mA max.

I work with ISO test specs on a daily basis and the trick is how to get the test to pass the ISO wording. Wether your product is bullet proof or junk. Not the thing for anyone to hear, but it's what happens in the real world.
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Old Jan 12, 2005, 3:11 PM   #18
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Red Man wrote:
Quote:
Sorry to chime in late.
Just to add my 2 cents in.
I haven't read the ISO spec. just what has been said here.
First is the test spec 24V @ 100mA a max, min or nominal test spec?
You should really download this spec - Do they have to?
Here the characteristics described on page 4: "... the camera is operated with a 24Vdc power supply and 240 Ohm resistor connected across the camera synchronizer terminal in series (see figure 6)..."
-> with a not so accurate 5% tolerance resistor it works out to be: 95.2mA ~ 105.2mA



Quote:
Second if the spec doesn't specify where the test is to be taken (across the Hot Shoe or the sync terminal)
The ISO-10330:2002 treats both terminal equally and does not make a distinction between the hot shoe or the sync terminal with their diagrams like some posters here would like to suggest otherwise...




Quote:
That would lead me to think the test spec is worded 24V @100mA max.
Correct - This is the margin that the spec allows for the photographer to setup his studio! Again from a quote on page 14 of the ISO-10330: "The requirements given in 4.2 (ie. any 1 of the photoflash units shall be 30mA at maximum) permit up to three photoflash units to be connected in parallel with a single camera. When more than three photoflash units are connected in parallel with a single camera, care should be taken not to cause the sum of the currents flowing through the camera to exceed 100mA."


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Old Jan 12, 2005, 10:15 PM   #19
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NHL

O.K. this voltage thing is getting annoying.
Just for kicks I called Canon support and they do recommend
Wein safesync to limit the voltage going across the hotshoe
to 6v. They also said that all EOS digital cameras and the 1V and EOS 3 are propitary systems that are set up
to 6v spec.
This is saying to me that the 24V spec is a max voltage. Which would mean as long as the sync works below 24v max it's is a pass.

The way you read the spec it sounds like it is a nominal voltage which would mean you have to test at 24v +/-some small voltage for tolerance. Which to me sounds correct.

I need to read this ISO spec. Has anyone out there downloaded it and could they email it?

If the studio flash triggered by a 24v power supply with a 240 ohm resister I have to assume the resistor is there to stop a voltage spike along the cable going to the flash heads. Let me know if I'm wrong on that.

If the voltage spike in a feed back can get around that resistor then yes it would cook the circuit, but in the case of a proprietary board the camera would be cooked. Proprietary circuits are great for cost but when everything is connected to it, if it goes the whole thing is dead.

The tech guy in a round about way said that they can't be sure on 3rd party equipment attached to their camera would match their specs.
In other words they can't be sure the hot shoe won't get a voltage feed back.

Electrical current is like water if it can travel in a different path it will. So if there is a problem with current going back to the camera and can get around the resistor it could cook the board.

In short it sounds a lot like they are getting around the ISO spec. Who knows how but Canon and Nikon are both saying things short of 24v.

Just makes me a little nervous about not using a safesync.
They know something we don't and they don't want to admit any problems.



Just thought of this: (The follwing morning)

If the cameras (Whatever make) are being tested and passing test to the ISO standard. After the cameras are release to the public and the manufacturers are seeing meltdown problems occuring with 3rd party equipment.
The manufacturers don't know what we are using and if it's in good working order, they just know that there is a problem with some users. Then they can say here's the voltage we recomend which is the voltage that their board can take, not the circuit of the hot shoe.

Yes they can get away with this.

Wein Safesync around a hundred dollars is starting to sound good.

Just my thoughts

Hey on another note you gave another member advise on Lumiquest systems. They work great thanks.
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Old Jan 13, 2005, 8:45 AM   #20
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Red Man wrote:
Quote:
O.K. this voltage thing is getting annoying.
Just for kicks I called Canon support and they do recommend
Wein safesync to limit the voltage going across the hotshoe
to 6v. They also said that all EOS digital cameras and the 1V and EOS 3 are propitary systems that are set up to 6v spec.
Trust me - I'm annoyed more than anyone here:
I have been using my Metz and Sunpaks handle mounts units (the workhorses of most wedding photographers) on all my cameras for over dozen of years from the Canon F1, A1, to the EOS (including the Minolta and recently a Nikon F5) - I hear you too, 6V max??? - At least 1 of my camera should be kaput!!! - Yes?



Quote:
If the studio flash triggered by a 24v power supply with a 240 ohm resister I have to assume the resistor is there to stop a voltage spike along the cable going to the flash heads. Let me know if I'm wrong on that.
According to Ohm law: V = R x I, with V = 24V and R = 240 -> I is then 100mA, the limiting current! Taking into account the tolerance of the resistor 240 (+/- 5% for example). The camera must then be able to pass 95.2mA to 105.2mA through its contacts (mechanical or electronics).

Protection against spikes is provided by a zener as in figure B.7 of the Annex B in the ISO-10330 - This diode clips the higher voltage just like any back EMF from a relay closure



Quote:
In short it sounds a lot like they are getting around the ISO spec.
If the ISO "Electrical Characteristics and Test Methods" calls for a 24Vdc power supply, clearly pictured a set-up with waveforms and the timing information - someone is "cooking" the book in using a lower power supply - The ISO 9000/1 quality control clearly prevents this from happening! :?



Quote:
Wein Safesync around a hundred dollars is starting to sound good.
Such devices are actually described in the ISO-10330 annexes as well - They are used to 'amplify' the current.
Remember each camera can only sink 3 flashes? You can now overcome this limation by cascading 3 of theses devices to sync 9 or more flashes to the camera



Also as a sidenote: Most electronics got to have ESD protection for their open contacts - Take the USB port for example it's only rated for 4.75 to 5.25V, but they all need to have protection or the manufacturers will see lots of return - they'll put it in for their own good! :?
http://www.semtech.com/pdf/si96-18.pdf
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