[Tanzer]

This is using the AF540FGZii, using it's on-board optical trigger. I've had similar results with the AF360FGZ.

Camera settings: 1/100 sec, f/8, ISO 100, on-board flash exposure compensation set to -2.0 EV.
Flash settings: 1/4 power, "S2" dumb slave mode (which is functionally the same as a cheap external trigger -- fires with every flash and does not ignore the pre-flash). The flash is at 90 degrees to camera right.

Using the same flash unit, but in manual mode and with an external optical slave module, did not work, which is what I expected. The external module and/or the hotshoe circuitry is just too slow for the MX-1, but will work fine on a dSLR because of its much slower preflash and mirror flip sequence.

By the way, not sure I understood the previous comments about shooting in manual, but if you meant manual exposure mode on the MX-1's mode dial, note that the camera will still fire the pre-flash. There is no manual control for the on-board flash, just as there is no manual flash control for the on-board flash on the K-5 -- just flash exposure compensation.

Attached Images

View Picture EXIF

File Date

 

---

Last edited by Tanzer; 12-13-2013 at 10:06 PM.

[Steve.Ledger]

I didn't really follow anything you said there, sorry.

I'm working with the Yongnuo 560III and a Pentax MX-1.
There is no hot shoe, of course.

Setting the camera 1/100 sec, f/8, ISO 100 and the YN560II to S2 (for pre flash detection) doesn't work. Neither does S1 (flash to flash).
I've proven that nothing works because there's not a single setting left to try on the camera or the speedlight.
As already mention, it works fine with all other Pentax cams I have.

By 'manual' I mean to set the MX-1 on-board flash to 'flash' and dial down or up the power.

[Tanzer]

Just demonstrating for the OP and for the general membership that some optical triggers, such as those which are built-in on the Pentax 360 and 540, can work fine, without any pre-flash suppression.

I wasn't attempting to address your particular situation, since I don't have the Youngnuo. You are using a fractional power setting (like 1/4 or less), right? If so, my guess is that its trigger circuitry is just too slow.

[Steve.Ledger]

Sorry, I assumed you were responding to my question directed to you some days ago (see Post #10)

my guess is that its trigger circuitry is just too slow

Not sure what you mean by "trigger circuitry too low" - note that the Yonguo is triggered just fine by all other Pentax dcams I own (K-7/K-01/Q) - also the MX-1 triggers it as well, just not in sync (though to the eye it is)

Thanks anyway, I've given up. It doesn't work and that's the end of it..

[lister6520]

In most flashes the trigger circuit also has to charge up. So even if you've used only a quarter of the energy in the main capacitor the trigger circuit is fully discharged regardless of the power setting and needs its time to recharge. Normally that will be in the range of 1/20 to 1/5 of a second.

[Steve.Ledger]

Yes I am aware of this. The point is not the triggering, it's the syncing. Thanks

[Tanzer]

Not sure what you mean by "trigger circuitry too low" - note that the Yonguo is triggered just fine by all other Pentax dcams I own (K-7/K-01/Q)

Again, dSLRs like the K-7 have noticeably slower pre-flash sequences due to the mirror flip. (By "noticeably", I mean you can easily tell just looking at the flash sequence in a bathroom mirror.) The K-01 doesn't have a mirror to flip, but it appears all the mechanical bits are there which slows things down as if it had one. Even a flash with a separate third-party hotshoe-mounted external optical trigger will trigger off these slower cameras.

For the MX-1 and other cameras with purely electronic shutters like my X-90, their sequence is noticeably much faster so those are another story. YMMV depending on the particulars of your flash. But looking at Luke's picture, we can at least say, as one datapoint, that the Pentax P-TTL flashes will work with their internal optical triggers. I'm not trying to promote Pentax flashes as better than anyone else's, just trying to show that it can work. Maybe some of the Metz or Simga models will too, I don't know.

Sorry, I assumed you were responding to my question directed to you some days ago (see Post #10)

Well I thought the information might be useful to anyone. Sorry if I wasted your time sending you down a frustrating dead-end, but I didn't know your setup at that time.

[Steve.Ledger]

Thanks.
But then the Q has electronic shutter and it works just fine with that camera.
You can disable the electronic shutter in the MX-1. Either way, still doesn't sync (will flash - but not in sync).

You haven't wasted my time, I appreciate all constructive and helpful comments regarding this issue.
I have tried every conceivable setting to get the 560III and MX-1 to sync, nothing works. Flashing isn't the problem, it's the synchronisation of the flashes.

[geoffw]

Evening all. I've tried playing about a little bit but need to fine tune to get better results. In brief. Set a slow-ish shutter speed, about a third of a second, ND filter on, down rate the camera flash 2 stops, f8, trailing curtain sync and the viv 283 on auto yellow mode and it syncs with the camera. But a I said, I still need to fine tune things, but its coming.

[Steve.Ledger]

Gosh, Geoff... That actually worked!
In fact I've found that any shutter speed up to 1/100 will sync the flash. Once you get to 1/125 it will flash but not sync.
I feel a little stupid now, could have sworn I tried all those combinations before, I didn't consider the ND filter...BUT... I just found it still works with the ND filter 'off' and at any F stop ! Seems the slow sync is the key (but I KNOW I tried that before! - weird. Butterfly effect perhaps )

Just goes to show, more than one person working on a problem often turns up a solution, cheers Geoff!

[geoffw]

Gosh, Geoff... That actually worked!
In fact I've found that any shutter speed up to 1/100 will sync the flash. Once you get to 1/125 it will flash but not sync.
I feel a little stupid now, could have sworn I tried all those combinations before, I didn't consider the ND filter...BUT... I just found it still works with the ND filter 'off' and at any F stop ! Seems the slow sync is the key (but I KNOW I tried that before! - weird. Butterfly effect perhaps )

Just goes to show, more than one person working on a problem often turns up a solution, cheers Geoff!

Cheers to you too Steve. Also thanks to all for helping stir the grey cells into think mode. Have a good Christmas all.

[Steve.Ledger]

Just a heads up.
I bought a cheap Godox CF-18 to throw in my small bag to use as a hand held fill flash with the Q and the MX-1.
It arrived today and while the Q works with it in S1 mode just fine the MX-1 does not. The only mode it works in is S3 (the CF-18 has up to S4) with the camera flash set to Red-Eye
At least it works..

[Steve.Ledger]

Better news. I had a bit more time to muck around with the GODOX and MX-1 combo.
This thing will sync up to 1/2000 !! (but not beyond)
It works in S2 and S3 modes of the GODOX slave.
IOW: S2 as normal flash and S3 as redeye

I've written down the settings and saved as a PDF for anyone else who might like to try the CF-18 slave flash. For the price (as low as $15 online) it's worth chucking one in the camera bag for sure.