Road Train !!!!!!!!!!

by Russell McMahon

submit your photo


Hall of Fame
View past winners from this year

Please participate in Meta
and help us grow.

Take the 2-minute tour ×
Photography Stack Exchange is a question and answer site for professional, enthusiast and amateur photographers. It's 100% free, no registration required.

I see that the cables that support TTL offered by manufacturers such as Canon and Nikon for using a flash off-camera are fairly spendy and that there are some third-party cables at a fraction of the price.

What does one risk/lose in using a third party cable as opposed to the name-brand offerings?

share|improve this question
1  
I think this question would apply to any camera-vendor-branded TTL cables, not just Canon and Nikon. –  mattdm Mar 14 '11 at 19:42
    
I suppose that's true. I'll update my wording. –  ahockley Mar 14 '11 at 19:51
    
A related question: If you are using a name-brand cable, does the camera know that your flash is off-camera, or does it work exactly as if it was on-camera? –  Jukka Suomela Mar 14 '11 at 22:17
    
@Jukka: Cameras don't know or care if their flash is off camera or not. They do their metering the same way, so... –  PearsonArtPhoto Mar 15 '11 at 0:48

1 Answer 1

up vote 6 down vote accepted

Apart from the fragility of the worst of the knock-offs (which are likely to carry name-brand markings at a way-too-good-to-be-a-white-lie prices), my worry would be adequate shielding and twisting together of the appropriate wire pairs/triplets. That would show up as a smearing of the signals (you'd need an oscilloscope to actually see it).

In functional terms, it could affect the WWT* signal on very short duration flashes (for really close work, near the flash's minimum rated range) and possibly the chatty control signals that go on during high-speed sync. At close ranges it could significantly overexpose; at longer ranges the extra microseconds won't make nearly as much of a difference. You can test HSS fairly easily -- if it doesn't work at high shutter speeds, you may still have a perfectly adequate cable for X-sync or longer.

If the cable is at all well-made, it should have no problem, but if it's more than a couple of feet long and is just a bunch of straight wires in a jacket, it might show high-speed signalling problems. If things are really, really bad, your neighbor's garage door might open every time you take a picture -- and if that happens, it's worth hanging onto the cable just for that.

*WWT is a TLA for the French Canadian exclamation, "whoa, whoa tabernac!" It's a common name for the shut-off signal in any piece of Canadian military electronics -- talking about the "WWT strobe voltage transient" is much more impressive to passers-by than talking about the off switch signal.

share|improve this answer
1  
I liked the bit about the garage door –  thomasrutter Mar 15 '11 at 1:30

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.