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Old Jan 12, 2005, 3:11 PM   #18
NHL
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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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