1/180 flash sync speed and remote trigger don't work properly... HELP needed

Started Oct 25, 2010 | Discussions
pentx4life
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1/180 flash sync speed and remote trigger don't work properly... HELP needed
Oct 25, 2010

Hi everyone, I bouth these flash triggers in ebay

http://cgi.ebay.de/RF602-Flash-Trigger-Pentax-K10D-K200D-with-3-Receivers-/220608314638?pt=Camera_Flash_Accessories&hash=item335d47bd0e

My problem is, that if I use the Flash-X-Sync mode with my Pentax K10D I always get a black part in the bottom area of the image. Why is that so? If I go in manual mode (first shot) and reduce the speed to 1/125 it works fine nearly all the time, but in X-syncmode it doesn't. Could it be, that the trigger system has its own sync speed of maybe only 1/125 and not 1/180? I don't get it.

If you have some Ideas, it would be great! Or is it a malfunction of the trigger system and I should send it back??

Thank you
Kevin

John Deerfield
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Re: 1/180 flash sync speed and remote trigger don't work properly... HELP needed
In reply to pentx4life, Oct 25, 2010

Your camera has a maximum sync of I am assuming 1/180th? But that doesn't mean that all triggers will be able to function @ that speed, especially wireless triggers. You could try to use a sync cable (wired!) and see if you can use the max. sync. speed. Or perhaps a better wireless trigger (Pocket Wizard) if you need wireless and max. sync speed. But even then, I would test a PW first. In any event, what you are seeing is the shutter curtain starting to close as the flash fires... so the two are NOT in sync. Using the slower shutter allows the flash to fire while the curtain is still open.

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nickoly
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Re: 1/180 flash sync speed and remote trigger don't work properly... HELP needed
In reply to pentx4life, Oct 25, 2010

It's caused by a delay in the trigger and the shutter is starting to close when the flash finally fires.

Interesting that you get the second curtain in different positions for the same shutter speed.

This seems to be a common problem with cheapo radio links. My camera will synch at 1/500 but I have to use 1/125 my cheapo eBay trigger. I don't understand why there should be a delay, electrons travel at nearly the speed of light, for chrissakes, and I have never had a problem with long cables.

I don't know if expensive trriggers are any better.

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gsrokmix
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Re: 1/180 flash sync speed and remote trigger don't work properly... HELP needed
In reply to nickoly, Oct 25, 2010

I use Cybersyncs with my K20D, they trigger fine at 1/180.

George

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Autodidact
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Re: 1/180 flash sync speed and remote trigger don't work properly... HELP needed
In reply to nickoly, Oct 25, 2010

This seems to be a common problem with cheapo radio links. My camera will synch at 1/500 but I have to use 1/125 my cheapo eBay trigger.

I've got a cheap trigger too, that only "works" at 1/125 on my Pentax K10. The odd thing is that my friends Nikon D700 syncs fine — above my cameras sync speed. So the body must be significant a factor in this behavior.

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keyboard_warrior
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Re: 1/180 flash sync speed and remote trigger don't work properly... HELP needed
In reply to Autodidact, Oct 25, 2010

Someone gave me a set of Calumet radio triggers that are very modestly priced - very reliable and will trigger my Metz's up to 100 yards ( not that I'd use them at that distance).

I too found the max sync speed of these units to be around 1/125 sec which is mostly no problem when used in a studio / indoor setting, but not terribly useful when used outdoors, unless the shutter speed is capped at 1/125 sec. If they'd sync at say 1/250 sec then they would be good value for money.

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UKphotographers
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Re: 1/180 flash sync speed and remote trigger don't work properly... HELP needed
In reply to Autodidact, Oct 25, 2010

Autodidact wrote:

This seems to be a common problem with cheapo radio links. My camera will synch at 1/500 but I have to use 1/125 my cheapo eBay trigger.

I've got a cheap trigger too, that only "works" at 1/125 on my Pentax K10. The odd thing is that my friends Nikon D700 syncs fine — above my cameras sync speed. So the body must be significant a factor in this behavior.

Like the previous poster, I've never ever had any problems with any radio triggers on my Nikons, even el cheapo ones. I've even had those working at 1/8000s. Every problem I've ever come across with these sorts of problems seem to be with non-Nikon cameras. I'm not a Nikon Fanboy, I just use them, it's very easy to search this whole forum for similar problems and see that what I'm saying is true.

The underlying problem with cheap radio triggers is iffy batteries. Change these first, if this doesn't resolve the issue then you're stuck at 1/125s. You could always give your ebay triggers to a friend with a Nikon, who I'm sure will make good use of them

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ColourBlind
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The triggers are probably fine
In reply to UKphotographers, Oct 25, 2010

I have 5 sets myself and find them to be fantastic bits of kit which will synch just slightly below the max of your camera. D3 max sync is 1/250 and they will synch without issue at 1/200th all day.

The issue could be batteries, or it could just be using it with Pentax.

What exactly is X-syncmode though?

Can you not just connect the trigger to the hotshoe and fire at a manual shutter speed of 1/160th or so, or is 1/125th the next lowest shutter speed?

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pentx4life
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Re: The triggers are probably fine
In reply to ColourBlind, Oct 25, 2010

Hi everyone!

Thanks for your comments! Helped a lot. So I think I will keep them, and keep firing at 1/125 should be fast enough for portraits I guess. And If I need faster shutter speed with one external flash I'll get a PTTL-Cord and use my Metz 58 AF-1.

Thank you all!
Kevin

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pentx4life
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Re: The triggers are probably fine
In reply to ColourBlind, Oct 25, 2010

From the K10D-Review
"Flash X-Sync

Designed only to be used with a flash. This mode simply selects the flash x-sync shutter speed, which is 1/180 sec, you can select the aperture using the rear dial"

I think its fancy but not necessary, I'll use M mode and just select 1/125 or longer.

Regards, Kevin

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Nikonparrothead
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Re: 1/180 flash sync speed and remote trigger don't work properly... HELP needed
In reply to nickoly, Oct 26, 2010

nickoly wrote:

It's caused by a delay in the trigger and the shutter is starting to close when the flash finally fires.

Interesting that you get the second curtain in different positions for the same shutter speed.

This seems to be a common problem with cheapo radio links. My camera will synch at 1/500 but I have to use 1/125 my cheapo eBay trigger. I don't understand why there should be a delay, electrons travel at nearly the speed of light, for chrissakes, and I have never had a problem with long cables.

I don't know if expensive trriggers are any better.

YMMV with triggers. I have some cheapies that will sync at 1/160 vs. 1/250 -- it is indeed the time it takes for the signal to travel.

I have some Elinchrom skyports that basically do the same. I forget if Pocket Wizards will work at 1/250.

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nickoly
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And cameras, apparently
In reply to Nikonparrothead, Oct 26, 2010

There is a similar thread nearby. It seems this delay is less of a problem with Nikon cameras.

Don't ask why....

The signal should be travelling at more or less 300,000 km/sec. I have never had a problem with a long cord. There must be something else going on. It might have something to do with charging capacitors, that is something that might have an identifiable time factor.

Nikonparrothead wrote:

YMMV with triggers. I have some cheapies that will sync at 1/160 vs. 1/250 -- it is indeed the time it takes for the signal to travel.

I have some Elinchrom skyports that basically do the same. I forget if Pocket Wizards will work at 1/250.

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UKphotographers
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Re: And cameras, apparently
In reply to nickoly, Oct 26, 2010

nickoly wrote:

There is a similar thread nearby. It seems this delay is less of a problem with Nikon cameras.

It does seem odd. Where is that thread?

Edit: Found it. http://forums.dpreview.com/forums/readflat.asp?forum=1025&message=36735037&changemode=1

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ProTL
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Re: 1/180 flash sync speed and remote trigger don't work properly... HELP needed
In reply to UKphotographers, Oct 26, 2010

I did a search on “reliability of yongnuo radio trigger” which turned up a lot of information and various opinions, mostly favorable. Some report a max sync of 1/125 and others say they’ve tested them beyond 1/250. As the previous poster commented batteries come up often.

As the old adage goes, the proof is in the pudding. So, with fresh batteries the max sync speed will be determined by your setup and the triggers you are using.

Here is some info for what its worth.

http://www.insidetheviewfinder.com/yongnuo-rf-602-wireless-remote-review/

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kenyee
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there's a long thread on pentaxforums on why
In reply to pentx4life, Oct 26, 2010

I helped figure out the problem when the RF602's first came out.

They use the half-press shutter release to transmit a "get ready" signal.

The Pentax pin that transmits this info behaves differently than the Nikon/Canon hotshoe, so the transmitter never really gets this signal properly. Hence the 1/125th sync speeds which I got as well.

I've been using Radiopopper JrX Studios for a year now and have been happily syncing at 1/180 w/ remote control of power levels of nikon speedlights and AB/WL studio strobes. Once you try them, you'll never go back to simple triggers...

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nickoly
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Is that a real explanation?
In reply to kenyee, Oct 26, 2010

I'm at the head of the queue, still, of those who don't understand why these delays happen. Two things are quite clear that makes this at best an explanation for a particular circumstance (and I even have doubts about that) being

1. the problem is not exclusive to Pentax

2. the problem is not exclusive to RF602

As far as I know, the problem was first manifest with the PT-04 cheapo triggers, and their ilk, before the RF-602s came out. I believe the RF-602 enables TTL control and, yes, I guess that could cloud the issue, but the cheapos have nothing but the centre pin.

This is a problem of timing. Even if there was a feeler signal at the half press, there is surely no way of determining how long that press would be, so I would be interested to hear how the same problem does not occur when using an ordinary Pentax flahgun in the same shoe and for which such a signal would have been intended in the first place.

kenyee wrote:

I helped figure out the problem when the RF602's first came out.

They use the half-press shutter release to transmit a "get ready" signal.

The Pentax pin that transmits this info behaves differently than the Nikon/Canon hotshoe, so the transmitter never really gets this signal properly. Hence the 1/125th sync speeds which I got as well.

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kenyee
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PT-04 had different issue
In reply to nickoly, Oct 28, 2010

nickoly wrote:

As far as I know, the problem was first manifest with the PT-04 cheapo triggers, and their ilk, before the RF-602s came out. I believe the RF-602 enables TTL control and, yes, I guess that could cloud the issue, but the cheapos have nothing but the centre pin.

I had the V2s (same as the PT-04 effectively) before the RF602's. The reason for their drop in sync speed was generally the battery dying on the transmitter.

I experienced this w/ the V2s before I sold them. Synced perfectly for me until the battery ran low, then it had a black band so I had to back off to 1/160.

The RF-602 issue as I described it is the real problem. People opened them up and hacked them to send the half-press signal all the time and it synced at 1/180 on Pentax.

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