I was in a camera store a few weeks ago and overheard this conversation between the sales clerk and a young blonde female customer.
Clerk: Hi, can I help you?
Woman: Yes, I want to buy a flash for my Canon camera.
C: What type?
W: An EOS (I can't remember the model - Dylan)
C: Oh gee, we are all out of Canon flashes. We'll have them in again in a few days.
W: Really? You don't have anything else?
C: Well we have aftermarket ones.
W: Can I get one of those?
C: Oh you NEVER want to use an aftermarket flash on your Canon because it can fry the camera!
W: Really?
C: Yes.


Well, that's the gist of it. Is this true or is it complete BS to try and talk the woman into a much more expensive flash? I know Canon won't cover damage from using aftermarket pieces, but to say outright that it will fry the camera is ridiculous. Obviously it won't because they wouldn't even sell them in the first place if it was true.
Any thoughts? I hear so much BS from camera sales people at local stores that I think they are worse than used car salesmen.

You mean to tell me there was a young blonde in need of photo education and you didn't step up to the plate?

I'm sooooo disappointed...

Oh no, you've now got my brain on camera innuendo....

I'd better log off before I type what I'm thinking.

Well.... there actually is an atom of truth in the salesman's remarks. While he may not have known it, his remark referred to the trigger voltage of flash units. Ancient strobes could send 100V, or far more, through the hot shoe during a flash. These high voltages could, indeed, fry the circuitry of newer camera (i.e. just about any camera manufactured in the last 8-10 years). Contemporary cameras generally expect trigger voltages less than 10V, often closer to 6V.

But it's relatively unlikely (at least to my knowledge) that any store sells any new on-camera flash that sends death-row trigger voltages today, although it might be possible to find such units on closet-clearance eBay sales.

In preparation for a potential future encounter with this bewildered young lass, here's a reference list of trigger voltages (http://www.botzilla.com/photo/strobeVolts.html) that some fellow with way too much time on his hands has diligently compiled with the help of many other folks. Print it out, shove it in your pocket and be ready to whip it out when you hang around the camera store next time.

The salesperson is right. A flash trigger voltage over 6V can mess up the electronics(some newer models like 20D and 1D can handle higher voltage) There still are flashes that have a trigger voltage that is higher than 6V(my friend tested his Vivitar 285HV and it was higher). You can get a Wein safe sync and use any flash you want.

Interesting!

On the other hand, if they sell Canon SLRs, why bother carrying flashes for Canon SLRs if they won't sell them to customers. Know what I mean? This shop isn't a serious camera store, rather a shopping mall based chain.

Some of them might have a universal mount so they can work with all cameras, some cameras can handle higher trigger voltage.