[Class A]

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class A: it's because of the half-shutter press pin (he's using the Canon TX)...read up in the thread a few pages...

Thanks for the reminder, but that's figmental1978's first posting in this thread so maybe you mixed him up with someone else?

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Last edited by Class A; 11-30-2009 at 04:12 PM.

[PolishMike]

Actually, I should probably post an update on these, since I have previously praised the Nikon-style transmitter as the solution to all Pentaxian problems.

The Nikon-style RF-602 has stopped working for me. I did a couple of shoots with them, syncing at 1/180 just fine, with the green light coming on as expected. After a couple of weeks, I was doing another strobist session and the Nikon Tx just failed horrifically on me - half the time the green light would not come on. Not only that, but when this happened, the Tx actually locked up and failed to sync even below 1/100. About 1/3 of the time, everything would work fine, but the rest of the time the flashes would fire so late I could watch them fire through the viewfinder - the mirror had time to return before they fired. Tried 3 different triggers, fresh batteries - the same triggers work just fine on Nikon body. Tried cleaning contacts etc...

Got back home, tried the Canon-style Tx, which syncs at 1/160, with banding at 1/180 - but I'm happy to work with this, since it's perfectly reliable.
I have no idea why triggers which worked about 95% reliably on all my previous tests and two several-hour sessions would just stop working altogether on the same camera, with the same firmware, lens, memory card, settings, etc... It's just odd.

More tedious details:
The behaviour is very weird - if I hold the Nikon Tx button half-pressed on the hotshoe and fire, it always syncs fine. If I have the Tx on the camera and half-press the shutter, sometimes the green light comes on (flickering rapidly, but triggering just fine - this is how it always used to be before) and sometimes it stays off (not triggering). If I half-press the Tx button while in this "failed" state, the green light fails to switch on! This seems to imply the digital stream the trigger is getting from the body is actually somehow locking up the trigger circuitry momentarily. Very, very odd.

[FotoPete]

I have the Canon Rebel variants (they use the same shutter release) and they work fine but I'm capped at 1/100th of a sec sync. Can be annoying at times. Might have to replace the battery or something.

[kenyee]

When I had the canon ones, I could only get 1/125 w/o banding too...

[figmental1978]

Mine are firing consistently at 1/160 in M mode when I replaced the Yongnuo battery with a Panasonic one but heavy banding at 1/180 in X mode.

I can now also sync at 1/180 without banding when I press the trigger button half way so a little tape should fix that.

[kenyee]

Mine are firing consistently at 1/160 in M mode when I replaced the Yongnuo battery with a Panasonic one but heavy banding at 1/180 in X mode.

If you look carefully, you might see light banding at 1/160....that's what I saw w/ mine.
At 1/180, it's *very* obvious...straight black line...
But yes, taping the trigger down should fix this problem, at the expense of battery life on the TX.

[figmental1978]

If you look carefully, you might see light banding at 1/160....that's what I saw w/ mine.
At 1/180, it's *very* obvious...straight black line...
But yes, taping the trigger down should fix this problem, at the expense of battery life on the TX.

I did get a slither of banding at 1/160 with the yongnuo battery but when I changed to the Panasonic it was gone. I guess taping the trigger on the TX will kill the battery quicker but it's a solution if you need the extra speed of 1/180.

[wussery]

On Strobist one the members posted this regarding how to get the 1/180 sec sync speed to work.

There is a difference between Nikon and Canon transmitters. For a Pentax the mfg would recommend a Canon TX, but the Nikon version is what you need. The wake-up will not work for Pentax with the Canon tx and sync speed was 1/160. With the Nikon Tx everything worked fine.

But you need to make sure you get the right cable:

If you order the Nikon system, make sure you ask them for the Canon shutter trigger cable, as that will fit directly into the Pentax K10D. The cable is not needed for the flash triggering though.

Here's the thread on Strobist:

Flickr: Discussing RF-602 Recevier Purchase Question in Strobist.com

[marcinski]

Hi
I have recently bough RF-602 triggers and they work flawlessly with my GX20 and old Sunpak flash at 1/180. No banding that I can see whatsoever.
Maybe the newer units have been improved or I got lucky, who knows.

Marcin

[GoremanX]

One thing these things are NOT is weather-proof, even in the slightest. I got my Rx very slightly damp yesterday, and now it triggers everything it touches. The moment I hook it up to anything (a flash, my camera), it triggers it right away and then acts like the shutter button is stuck on, thereby rendering the camera's shutter button useless. It does this whether I have batteries in it or not. Now I need a new Rx, and the only places that sell them are in China, which means another 2 week wait.

Why does everything that's made in China have to suck? (rhetorical)

Blah...

[systemA]

One thing these things are NOT is weather-proof, even in the slightest. I got my Rx very slightly damp yesterday, and now it triggers everything it touches. The moment I hook it up to anything (a flash, my camera), it triggers it right away and then acts like the shutter button is stuck on, thereby rendering the camera's shutter button useless. It does this whether I have batteries in it or not. Now I need a new Rx, and the only places that sell them are in China, which means another 2 week wait.

Why does everything that's made in China have to suck? (rhetorical)

Blah...

Ouch. Did you use it in light rain? Snow? What type of weather condition? I notice that the receivers (at least the pair I have) almost come apart if you bend the molding enough.

I have a set of Nikon Tx/Rx on the way and will post results when I get it. Also, I'm not sure if it was mentioned earlier, but 1/180 sync does work with the Canon/Pentax RF602 as long as the button on the transmitter is depressed, and the light is a stable green (seems to be a decoding issue).

[GoremanX]

Ouch. Did you use it in light rain? Snow? What type of weather condition? I notice that the receivers (at least the pair I have) almost come apart if you bend the molding enough.

I had the set in my camera bag, and the bag got wet while I was out walking in the rain. There was some dampness that got into the compartment where I keep the Tx/Rx. It wasn't much, just some mild surface wetness, but apparently it was enough to fry the electronics. Since it triggers everything I hook it up to regardless of whether there are batteries in it, I'm guessing it's grounding itself out.

I'll make sure and keep the new one in a ziplock bag from now on.

I wonder if the Chinese are proud of the reputation for poor quality their manufacturing industry is earning... but then they're raking in the dough and we're the ones giving them all our money, so I guess they ARE proud.

[pop4]

I'm gonna necro this thread since I ordered some Yongnuo RF-602 wireless flash triggers. They replace my Cactus V2s units, which don't seem to sync at anything faster than 1/30th, and even then, they are not reliable, not that they have ever been. I've checked and made sure all the batteries were charged and had the required voltages, I've tried both my K10D and K-7, I've tried different channels, but the issue is still there. I got my Yongnuo RF-602 wireless flash triggers on eBay through HK Yongnuo's eBay shop, buying a set with the Nikon transmitter (TX) and three receivers (RX). I also asked them to swap the shutter cable from one with a Nikon plug to the C1 plug that fits the K10D, K20D, K-7 and a few other cameras, which they happily did.

On the left is the wireless trigger set for Nikon. The difference between the Nikon and Canon sets is the hotshoe connector on the TX unit, see this dpreview thread for more details (scroll down a bit). All RX units are the same. In that box is one Nikon TX unit, a CR2 battery for the TX unit, one RX unit, 2x AAAs for the RX unit, a RX->flash cord (3.5mm jack), one 3.5mm-6.35mm adapter, and the instruction booklet. The green boxes are the RX boxes, which contain one RX unit, 2x AAAs for the RX unit, a RX->flash cord (3.5mm jack) and one 3.5mm-6.35mm adapter. The last box contains the shutter connecting cable, which ends in the 2.5mm stereo jack that Pentax cameras use for the shutter release.





Now, there have been issues with getting these Yongnuo RF-602 triggers to work properly with Pentax as per earlier this thread, on the dpreview link, on flickr, etc, and after doing a series of tests, here are my results:

Out of the box:
At 1/125th, I get full sync and 100% reliability.
At 1/160th, I get a feather of the rear shutter curtain (image A), and 100% reliability.
At 1/180th, I get full sync, but only at about 60% success rate. The other 40% of the time, the RX are triggered, but there is a complete mis-sync and the flashes don't contribute to the exposure; e.g. it's pretty much a dark frame. However, the RX units are triggered 100% of the time, so reliability between TX and RX unit is 100%.
However, if I half-press and hold down the button on the TX, and then take the shot, I get full sync at 100% reliability at 1/180th.
Also, when I turn the camera off, or the camera stops metering (p114 of the K-7 manual), these two instances will set off the RX unit as well.

Taking apart the TX and removing one of the pins, the one corresponding to "SP" on a Nikon hotshoe (see above dpreview link):
At 1/125th, I get full sync and 100% reliability.
At 1/160th, I get a feather of the rear shutter curtain (image A), and 100% reliability.
At 1/180th, I'll either get a feather of the rear shutter curtain (image A), or maybe a bit more of the rear curtain (image B), but, it will trigger 100% of the time.
Once again, if I do the half-press trick, I get full sync at 100% reliability at 1/180th.

Image A:


Image B:


It appears that what is happening is that the half-press signal of the TX unit needs to be triggered to tell the RX units to get ready in order to fully sync at 1/180th. This half-press can be done though manually pressing the button on the TX, or though half pressing the shutter button on the camera, which only works about 60% of the time, since I suspect the pin I removed is shorting between ground and digital signal on the Pentax hotshoe.

Despite all this, I'm actually quite content with these triggers, and the main thing is, the results are consistent and even though they might not sync properly, they trigger every time, something I can't say about the Cactus V2s units I had. I'll probably shoot at 1/160th and keep it in the back of my head that there'll be a slight feather at the bottom of the frame. And I guess if I need to shoot in x-sync mode (1/180th) and need it to sync, I can always do the half-press trick.

I had originally considered getting the Phottix Atlas wireless triggers, but their price, and the fact that they have not been confirmed to be working with the Pentax system at 1/180th, made me reconsider my options.

[Russell-Evans]

It appears that what is happening is that the half-press signal of the TX unit needs to be triggered to tell the RX units to get ready in order to fully sync at 1/180th.

With two transmitters, and two receivers, I set up an experiment where I mounted one transmitter in the receiver, and then had one transmitter on the camera, and the other receiver, remote with flash. Half press on the transmitter/receiver pair would lock the transmitter/receiver pair and the remote receiver into the green led mode. This had no affect on the transmitter on the camera. Its mode was independent. So even with the receivers in green led mode, the 1/125 sync was still in effect. Half pressing the transmitter on the camera to get it to green led mode gave the 1/180 sync. This leads me to believes it is only the transmitter that is the issue with the Pentax system.

Thank you
Russell

[pop4]

Thanks for that info. So it seems like the issue has something to do with the TX to Hotshoe communications.