so why did this happen?

[azpix]

snapping some shots tonights of my daughter, I have this black area creeping into the photos?

Now I've seen this before when I bump the camera past my sync speed to 1/320 or more, but these were all at 1/250th. Why would these be appearing?

much thanks!

http://www.coreyschimmel.com/why-1.jpg

http://www.coreyschimmel.com/why-2.jpg

[tkbslc]

what are you triggering the flash with?

[azpix]

elichrom skyports firing an alien bee 800.

[tkbslc]

Well that is the shutter you are seeing. You've obviously passed the sync speed limit for this setup. The 1/250 max sync speed is only guaranteed for Canon shoe flashes, so back off the shutter speed a bit. Maybe run some tests and see what your reliable max is.

I have heard of issues running at max sync with wireless triggers of all kinds, so this is not unusual.

[tim]

Shutter's too fast, use 1/125th. Mostly I get 1/250th with skyports and speedlites, but with studio strobes sometimes I need to go slower.

[Damian75]

Agreed sync speed issue and unless there is some ambient light creeping into your shots there is no need to crank the shutter up that high if your strobes are providing all the light then your flash duration is effectively your shutter speed when it come to freezing action so you should not have a problem.

[baw5t0n]

your camera can only sync at a certain speed - my 5D is only at 1/200. so if your camera's set at anything faster, it'll only capture a portion of the frame lit by flash. if you have ambient light in the frame that's properly exposed, you won't get that black box.

[jacuff]

Yeah, it's the shutter you are seeing. Start your shutter speed at 1/60 and work your way up to a faster shutter speed. This will help you determine the sync speed for this particular setup. The sync speed rating given by Canon is only for Canon Speedlites.

[BobbyM]

yep, what they said about sync speed...

http://photography-on-the.net/forum/showthread.php?t=429444 seems to be somewhat of a common problem.

http://photo.net/photography-lighting-equipment-techniques-forum/00KHiP << this guy came up with a DIY solution.

[PacAce]

yep, what they said about sync speed...

http://photography-on-the.net/forum/showthread.php?t=429444 seems to be somewhat of a common problem.

http://photo.net/photography-lighting-equipment-techniques-forum/00KHiP << this guy came up with a DIY solution.
That DIY solution is not to fixed a syncing problem as described in this thread. That DIY is for a junction box which distributes a sync signal from a single receiver to multiple strobes via cables.

[PacAce]

snapping some shots tonights of my daughter, I have this black area creeping into the photos?

Now I've seen this before when I bump the camera past my sync speed to 1/320 or more, but these were all at 1/250th. Why would these be appearing?

much thanks!

http://www.coreyschimmel.com/why-1.jpg

http://www.coreyschimmel.com/why-2.jpg

Are you having the syncing issue even after your Skyport receivers have been fully charged?

[BobbyM]

That DIY solution is not to fixed a syncing problem as described in this thread. That DIY is for a junction box which distributes a sync signal from a single receiver to multiple strobes via cables.

thanks for clearing that up then :oops:

[Jim M]

Since the band is at different locations in each photo, I presume the delay varied. Looks suspiciously like a battery issue. I don't know for sure about Skyports, but most radio triggers slow down and get kind of hinky with weak batteries.

[zagiace]

Strange shape for a sync issue. Should be a pretty straight edge to it.

I can sync with my 30D, AB, and Skyports at 250th. I get a little black but nowhere near that.

[azpix]

Are you having the syncing issue even after your Skyport receivers have been fully charged?

yes,
of the 20 shots, about 6 had the shutter creeping into them. i've used to exact same set up many times before at 250 without issue.

[azpix]

Since the band is at different locations in each photo, I presume the delay varied. Looks suspiciously like a battery issue. I don't know for sure about Skyports, but most radio triggers slow down and get kind of hinky with weak batteries.

the receivers were charged, I'll check the battery the transmitter.

[CliveyBoy]

And in the camera. The mirror has to be yanked up (the Canon clunk) and the mechanical shutter leaves opened at high speed. This power drain can slow up performance a little.

[azpix]

new battery in the transmitter and all is good

[Papa Carlo]

I see this with cactus triggers when the batteries are low. Not sure if skyports do the same.

[PacAce]

I see this with cactus triggers when the batteries are low. Not sure if skyports do the same.

I'm sure this could happen with any remote unit if the batteries are running low.