6D flash sync problem; flash not reporting to body? Firmware glitch? User error?

[ScottyP]

I was shooting my 6D today at the aviary. I believe I was in TV mode. Had my Canon 320EX speedlite on. I had been shooting with the flash off but turned it on. The shutter was set at 1/400th. The ISO was, I know, still set from the last room I was in, which was dark, so it is at ISO 3200. 

All the birds depicted were actually whole animals; no half-birds were anywhere to be seen. 

Anyway, the camera failed to reduce the shutter to the camera's max sync speed (1/180) like you expect it to do. As a result, the flash was clearly out of sync with the shutter.

Also, the metadata says "flash did not fire". But obviously it did fire.

Could this be a firmware glitch? Bad camera? Some obvious user error I am overlooking?

[cicopo · Accepted solution]

Assuming the flash & camera are 100% compatible (newer models of bodies aren't always happy with older strobes) AND based on some problems I've had with my 1Ds2 & 580 EX it may be that the flash isn't as far forward into the hot shoe as possible, or even if it is it's not making PERFECT connections on all 5 terminals. I've had that problem a few times & now check for it. If I don't get the result I expect on my test shots (to check exposure) I wiggle & re adjust until I do get the right result.

[ScottyP]

Update:  I actually checked how well the flash was mounted, per Cicopo.  To my surprise, although the tightening lever was deployed and everything, the speedlite WAS slid back in the hotshoe mount, and by quite a lot

.

I pushed it back forward like it is supposed to be and suddenly the camera is doing what it should.  I set it in TV and selected 1/640th shutter.  Took a few underexposed test-shots, and then turned on the speedlite.  BANG.  The camera overrode my shutter setting and reduced my shutter speed to 1/180th.  It worked 3 times, so I am calling this SOLVED.

On the other hand, this makes me wonder if you could trick the camera and "squeek"  a little higher sync speed out of the camera (just 1/250th maybe) by deliberately mis-mounting the flash in the hotshoe.  Surely some Strobist out there has tried this and it does not work well.

This is so simple it does make me feel a little silly, but I'd rather feel silly than have a real problem with my camera.

[cicopo]

Nice to know that's all it was. Fortunately it didn't spoil an important shoot. It did in my first case & tried again at my birthday party a few months back. .

[ScottyP]

Thanks Cicopo for the well-grounded, real-world, entirely successful solution!

By the way, if you don't mind revealing secrets, what does "CICOPO" mean?  Anything to do with Cambridge In Color?

[cicopo]

Nothing to do with them. Relates to the business I'm in, which is GM Muscle car restoration. It was the personal plate from a 69 Camaro I used to own. CI = Cast Iron (there was also an Aluminum version) 427 cu in 425 HP engine special option 69 Camaro known as a COPO (central office production order)

http://www.camaros.org/copo.shtml

I've used that screen name since getting internet service so it helps when people from other forums join one I'm on. Photography is essential in my business plus it's been a hobby I've enjoyed even before starting the business. Much more into land based photography but a terrible "people" photographer. I'll be doing some underwater stuff in 3 weeks while on vacation.