Vivitar 283 and 40D .Will it work?

digadv wrote in post #6015941
Well, I just read the manual ... page 106 of the 40D manual (bottom of the page). The PC port is rated at <250V. I don't see the same spec for the hotshoe, so better safe than sorry and keep it off the hotshoe (which I have read is rated at 6V but can't confirm).

Personally, I have modified my 283 (+200V) to work with sync voltages at 6V.



You're making a hugh assumption that the same circuit is triggering both ports. Personally, I would not take the chance.

The one thing I don't do in this forum is make unsubstantiated statements or assumptions without noting that fact, especially if it could involve possible damage to camera gear or equipment. But, for the record, I never said anything about the PC terminal and the hotshoe circuits being the same. You just made an assumption that I said that.

If you check out the March 2007 issue of Tech Tips in the Digital Journalist online magazine, Chuck Westfall states that the rating of trigger voltages apply equally to both the PC terminal and the hot shoe.

A snippet from http://digitaljournali​st.org/issue0703/tech-tips.html

@PacAce

I'm certainly not trying to accuse you of anything, and like you, just trying to err on the side of safety. I read the article and sincerely hope it's true. I wonder why Canon won't publish the electrical spec for the hotshoe.

Take care.

digadv wrote in post #6016289
@PacAce

I'm certainly not trying to accuse you of anything, and like you, just trying to err on the side of safety. I read the article (btw, please remove the ":" so that the link is correct) and sincerely hope it's true. I wonder why Canon won't publish the electrical spec for the hotshoe.

Take care.

Thanks for pointing out the error in the URL link. It's fixed now.

As for Canon not publishing any electrical specs, whatever Chuch Westfall says or publishes is as good as you're going to get from Canon. Without him, we'd be a lot deeper in the dark.

What I really want to know if anyone has tried putting a high-voltage 283 on their hotshoe and does it work? I had to disconnect my wires to the hotshoe contacts, but would reconnect them if it's safe.

BTW, 200+ VDC will wake you up if you're not careful .

digadv wrote in post #6016353
What I really want to know if anyone has tried putting a high-voltage 283 on their hotshoe and does it work? I had to disconnect my wires to the hotshoe contacts, but would reconnect them if it's safe.

BTW, 200+ VDC will wake you up if you're not careful .

The highest voltage the Canon EOS DSLR is rate at is 250V. I don't think it would be wise to try using a flash with a 283V trigger voltage without some form of protection!

[EDIT: I think I misread the previous post. I guess "high-voltage 283" was referring to the model number and not the actual voltage.

Anyway, according to Botzilla, I wouldn't risk using that flash directly with the camera unless you've measured the actual voltage with a good VOM and can see for a fact that the voltage is within safe limits: http://www.botzilla.co​m/photo/strobeVolts.ht​ml

digadv wrote in post #6016353
What I really want to know if anyone has tried putting a high-voltage 283 on their hotshoe and does it work? I had to disconnect my wires to the hotshoe contacts, but would reconnect them if it's safe.

BTW, 200+ VDC will wake you up if you're not careful .

I experienced that in college (electronics engineering lab) when I absentmindedly touched the bare metal part of a probe I was using to measure a voltage of DC power supply which had 200+ VDC across it. I wasn't looking at the terminal when I did that (I was looking down at the lab notes). I felt the jolt so I thought someone had punched my arms but there was nobody there when I turned around to see who did it. Good thing it was DC instead of AC. That's when I really learned to respect electricity and not take it for granted!

I think I will use my ebay triggers

Don't worry about voltage... static electricity has a ridiculously high voltage. It's current that kills.

PC Sync and hotshoe have the same voltage limit. As pointed out by PacAce, Chuck Westfall has confirmed it, and I've personally used my 283 (at 103vDC) a multitude of times on my 20D with no ill effects.

SolidxSnake wrote in post #6017059
Don't worry about voltage... static electricity has a ridiculously high voltage. It's current that kills.

PC Sync and hotshoe have the same voltage limit. As pointed out by PacAce, Chuck Westfall has confirmed it, and I've personally used my 283 (at 103vDC) a multitude of times on my 20D with no ill effects.

Have you ever seen the warnings about discharging the static electricity on your body before handling RAM memory boards or any but especially delicate electronic components or equipment?

BTW, Current (I) = Voltage (V) / Resistance (R). If the resistance is very low, you can get a lot of current flowing through even with low voltages. Lucky our body has a relative high resistance or those 9V batteries could be deadly.

PacAce wrote in post #6017245
Have you ever seen the warnings about discharging the static electricity on your body before handling RAM memory boards or any but especially delicate electronic components or equipment?

BTW, Current (I) = Voltage (V) / Resistance (R). If the resistance is very low, you can get a lot of current flowing through even with low voltages. Lucky our body has a relative high resistance or those 9V batteries could be deadly.

Electrostatic Discharge (ESD). The static in your body could essentially fry pretty much any sensitive electronic component. I've been working computers and loads of electronics since the ripe old age of 4 (around 12 years now) and I've never once worn a grounding strap on my wrist. Never killed anything with ESD either. I also work on carpet and my bedsheets. I guess I'm just lucky

SolidxSnake wrote in post #6017812
Electrostatic Discharge (ESD). The static in your body could essentially fry pretty much any sensitive electronic component. I've been working computers and loads of electronics since the ripe old age of 4 (around 12 years now) and I've never once worn a grounding strap on my wrist. Never killed anything with ESD either. I also work on carpet and my bedsheets. I guess I'm just lucky

Yes, you are (unless you automatically touch the chassis first). And remind me never to call you when I need my computer fixed.

PacAce wrote in post #6018866
Yes, you are (unless you automatically touch the chassis first). And remind me never to call you when I need my computer fixed.

If you pay then I'll make sure to remind you. It's getting old fixing everyone's computers for free

I do automatically touch the chassis though... much of the time it's after I unplug it from the wall (thus it's not grounded)