odd syncing issue

digitalfailure

digitalfailure

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Brian
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I'm hoping someone can give me an explanation on why I can see me shutter on my images when using studio lights :thinking:

Before everyone jumps up and says sync speed issue, allow me to elaborate a little.

If I use Bowens lights at 1/125th on my 5d2 I have no problems, I shot the other night with some lights and the same settings caused the black curtain of doom on my first image.

The sync speed of the 5d is 1/200th iirc so not sure why I had to drop to 1/100th to remove the curtain.
 
If you are using a wireless trigger check the batteries as this can cause the problem.
 
they were a different brand, elenchromes iirc and yup using someone else's radio trigger, dropping from 125 to 100 solved the issue, but thats much much slower than the camera can take even at 125th.
 
Like Dave said, batteries in the radio triggers can cause this, if they are running down apparently, there was a thread a few months ago on here that turned out ot be the same issue, they just dont trigger the lighst quick enough to synch with camera.
 
Very few radio triggers will match the max x-sync speed, certainly none of the cheaper ones. There is a fractional delay in the processor. Pocket Wizards will do it though and the new TTL ones will even allow a slight increase through clever custom 'Hypersync' timing.

I use RF-602 on a 5D2 and they need 1/160sec to clear with fresh batteries. I don't know what they do on low batts but what David says sounds right.
 
I've enquired about the brand of the triggers and it appears that they were the cheap yuoung something or others :(

I use twinlink triggers and they are faultless right up to the cameras max sync speed.

Whats really baffling me though is who dropping the shutter speed removed the issue, :thinking:
 
Hi Brian,

Generally speaking, when the batteries are running down a touch, there's a lag between the signal being transmitted and then received prior to the actual flash... That'll account for the shutter curtain appearing in the shot.

I've been using my RF-602's at 1/200sec with no problems (although it's got fresh batteries in) but I generally drop back to either 1/160 or 1/125 just to be on the safe side.

Si
 
digitalfailure said:
Gotcha :thumbs:

Next time I use his studio i'll take my twinlinks :)
Click to expand...

The delay in radio triggers is in the signal processing. With optical triggers it's virtually instantaneous but with radio the signal has to be received from the camera, converted to radio, transmitted (obviously that bit's pretty fast), received and processed again, before the flash can fire.

The dark line is a shadow of the second shutter curtain closing. It runs from top to bottom, but because the image on the sensor is inverted it appears at the bottom of the frame. If you make the shutter speed longer, there's more time before the second curtain closes and so all is well.

With my Yongnuo RF-602 you can almost get away with 1/200sec (normal max x-sync speed) on the 5D2 and there's only minimal shadowing. It's getawayable with many subjects. Same with my 40D which was similar up to 1/250sec. But with studio shooting there's no advanatge in pushing the sync speed right up so anything above about 1/60sec will be pretty much okay. 1/125sec seems to work fine even with the most basic triggers.

Those TwinLinks are interesting, having both IR and radio options. It would be interesting to see what the difference is. I'm guessing that the radio option will need a slighly slower x-sync speed than the IR option.
 
The delay must have been massive to have to drop to 100th though, 125th is no bother at all on every other system I've used.

The twinlinks are pretty awesome value tbh, the ir is a bit weak in bright light if only using that to fire the main light. using the full system on the bowens lights with both 5d1 and 5d2 i've not had a single misfire. And it's very impressive with the speedlite on the receiver too.
 
digitalfailure said:
The delay must have been massive to have to drop to 100th though, 125th is no bother at all on every other system I've used.

The twinlinks are pretty awesome value tbh, the ir is a bit weak in bright light if only using that to fire the main light. using the full system on the bowens lights with both 5d1 and 5d2 i've not had a single misfire. And it's very impressive with the speedlite on the receiver too.
Click to expand...

tis a shagged battery thing :(
 
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