430EX II Speedlite Attachment

[hp_chic]

Hi Guys,

Are there any professionals here who know if connecting the 430EX II when it and the camera (T5i) are both ON damages anything? I know that the user manual says the Speedlite should be OFF before attaching it to the hot shoe. I failed to follow that guideline several times before I read the manual... just wanna make sure.

Thanks.

[MikeSowsun · Accepted solution]

It is probably a good precaution but I doubt you will cause any damage if you leave the power on.  

I have been using Canon cameras and flash units for over 30 years.  I never turn off the camera or flash when I attach them or take them off, and have not had any problems of any kind.

I just went through a few of my older manuals and discovered that while newer flash units like the 600EX, 430EX II. 270EX, 270EX II, 320EX, and 90EX all say to turn off the power while attaching the flash,   older units like the 580EX II, 430EX, 420EX, etc, do not have this warning. 

[Skirball]

It never even dawned on me to consider turning them off before attaching/removing.  But what do I know, I'll swap lenses without turning off my camera if I'm tethered.

[hp_chic]

Thanks!

[AllNoAll]

I think this advice by Canon in your manual is an extreme precaution on their part. With my little knowledge of electrical theory it is possible to cause damage if both units are on but you would have to be moving extremely slow; basically there is an extremely small chance that when the two unit get very close to each other without a solid connection the small amount of electricity that could be present at each contact could arc causing a power surge in either or both units. With how little amount of electricity is present it is extremely unlikely this would ever happen.