Is it safe to have a Nikon Body and a Canon flash, triggered via Flash Triggers?

I have been trying to search this question. Heres the story (as always), i have a Nikon D80 Body, and i don't have a speedlight (Flash Gun) and may built-in-flash is broken cause its already long term. Now, i want to use a Speedlight for the biggest event of my life- YET. And i have found new information that if your put the trigger on a Nikon Body, and put the receiver trigger on a Canon Speedlight, lets say Canon 430ex Speedlight, it will work- this is true based on my friends expereince. BUT THE QUESTION IS- IS IT SAFE? That Nikon is sending to a Canon Speedlight via Flash triggers? Cause my friend who owns the speedlight is concerned. ANY ADVICE? TIPS Please?

and don't say look for a Nikon Speedlight, cause i have done that- and failed.

The camera has no idea what flash is being controlled that way, all it does is send a signal to fire. Won't hurt either one in any way. May or may not work at all, for that matter. Using dedicated TTL flashes off cheap radio triggers is a hit-or-miss thing… The flash may not even fire at all.

As long as you are using a radio trigger, the flash should work. But you will have to put everything into manual; Canon's ETTL system won't understand the Nikon's iTTL system.

When using manual, it will take some time to dial in the correct exposures, but it can be done.

Do not try to use a wired cable between the Nikon and Canon. For one, it won't help as the Canon flash's ETTL is not compatible with Nikon's iTTL, and the worst case, especially if the Canon flash is older, there might be more than 6V on the shoe.

Older cameras had mechanical contacts for the flash sync. These could tolerate almost any voltage as they were simply mechanical. Older flashes presented higher voltages on the shoe, but there was no problem.

DSLRs on the other hand have electronic contacts for the flash sync. The main issue is that they expect to see a low voltage (under 6Volts) from the flash. If you use an older flash on a newer camera, you could damage the camera - even if the flash and camera are the same brand. This varies wildly between cameras and flashes, so there's no one rule to cover them all.

But if you have to use this kind of setup, you can buy a voltage-isolated hot-shoe adapter that allows you to use a DSLR on an older flash.

But if your friend is worried about you using his flash, just ask to use his flash and camera. It will be far easier than trying to setup a flash-trigger and dial in manual exposure unless you are adept at doing so.

An alternative is to buy a cheap 3rd party flash for your camera. Some of those will do iTTL; perhaps a Vivitar or Targus. While they are cheap, they do work, sort of. The problem is that they won't last as long as a camera brand flash. But you will then be able to mount the flash on your hot-shoe, and not fiddle with manual exposure.

But you can buy one for $40 or less, which is no more expensive than having to buy a set of flash triggers.