Flash sync

geoffw · 11-27-2013, 02:07 PM

Hi. Is there a reason anybody knows of why a remote flash, couple with a slave trigger, will not sync using the built in flash on a MX1 or a K200d. The flash fires ok but not in sync with the shutter judging from the result.

**jatrax** · 11-27-2013, 02:20 PM

Generally the remote flash with optical slave trigger goes off when the camera fires a pre-flash for P-TTL metering. And therefore that will not work. A remote flash has to be P-TTL compatible in order to function properly with optical triggering from the camera.

The K-3 now has a manual flash mode that does not have a pre-flash and theoretically it should be possible for this to work in that mode, although I have not tried it yet.

In your case the only option (assuming the remote is not P-TTL) is to use wireless radio triggers or a cable.

elliott · 11-27-2013, 02:23 PM

What brand of optical triggers are you using? Some are able to ignore the P-TTL pre-flash, but many are not.

lister6520 · 11-27-2013, 02:29 PM

Is the slave trigger optical or radio? By optical I mean it triggers when it sees the light of the on camera flash.

If so then it is a problem common to most cameras. The reason is that the camera will fire a 'pre-flash' before the actual exposure. It does this to measure how much power it will need to put into the flash for the actual exposure. Unfortunately the slave trigger will 'see' that pre-flash causing it to trigger before the shutter opens. Then when the camera fires the main flash burst the slave flash would be recharging its trigger circuit (and possibly the main capacitor) and would not be able to flash that second time when it is actually needed.

There are solutions for this but they depend on the capabilites of the camera and the flash trigger.

On the camera side what can sometimes be done is to set the onboard flash to manual exposure as with some cameras this disables the pre-flash which is causing the problem. Here I don;t mean manual exposure of the shutter but of the flash power.

The other solution lies within the trigger. Some triggers 'know' about pre-flashes and have settings which allow them to ignore the pre-flash and only fire on the main flash. This is usually set by a very small slider switch on the trigger, or in the case of a flash with built in optical trigger it might even be a setting in the menu on the LCD.

Sometimes there are two or even three choices of this setting, this because some cameras issue more than one pre-flash. You don;t really need to know how many flashes the camera produces and instead would just find by trial and error which one works best.

geoffw · 11-27-2013, 02:36 PM

Thanks for your replies. Looks like the pre flash may be the issue. I'm using an old optical slave that I have to say I'm suprised it works and an old vivitar 283. I'm thinking I need to go shopping to get this sorted. Thanks again peeps.

**Just1MoreDave** · 11-27-2013, 02:59 PM

If you are using a low flash power on the slave, you could try to use the 2 second delay (K200D has it, don't know about the MX1). When the delay is used, the preflash fires first, then the 2 second delay, then the main flash. So if your slave is ready to fire again in 2 seconds, it will work. The 12 second delay might work the same way.

**JimJohnson** · 11-27-2013, 03:32 PM

You want a Seagull SYK-5 optical slave for use with older flashes triggered by the built in flash-
https://www.pentaxforums.com/forums/125-flashes-lighting-studio/187513-seagul...tructions.html

You can purchase them for well under US$20.

Tanzer · 11-27-2013, 04:13 PM

If you set the Vivitar on one of the auto modes, it might work okay.

Auto mode will limit the flash output, depending on the distance from flash to subject. Which will keep the capacitor charged and ready for the second flash.

This works with all of my old flashes and my SLRs/DSLRs, because the time between pre-flash and main flash is kinda slow (due to mirror flipping up).

But for mirrorless cameras like my Q and my X-90, the time between pre-flash and main flash is really fast, and only some of my triggers/flashes can keep up with them. I haven't tried my MX-1 yet -- maybe I will this weekend.

By necessity, this method will only work if you are firing on less than 1/2 power, maybe less (which is why some old flashes have a single low-power setting, like 1/16). And auto mode at the flash's position might give you unpredictable results, looking at your scene from the camera's perspective.

But it won't cost you anything to try it out. It should work on your K200d at least.

geoffw · 11-28-2013, 06:40 AM

Thanks Dave Tanser & Jim. Good food for thought. Will try & have a play around at the weekend.

Steve.Ledger · 12-10-2013, 06:31 PM

Originally posted by Tanzer

But for mirrorless cameras like my Q and my X-90, the time between pre-flash and main flash is really fast, and only some of my triggers/flashes can keep up with them. I haven't tried my MX-1 yet -- maybe I will this weekend.

What did you find?
I can't get an optical slave to sync with the MX-1
Both flash, but only the camera flash is recorded.

geoffw · 12-12-2013, 01:36 PM

Tried to get the MX1 to sync but no joy. Given up for now.

geoffw · 12-12-2013, 01:37 PM

Originally posted by Steve.Ledger

What did you find?
I can't get an optical slave to sync with the MX-1
Both flash, but only the camera flash is recorded.

Same as that Steve.

Steve.Ledger · 12-12-2013, 01:46 PM

Something is wrong then, on manual setting it should sync just fine like the other cams do. Maybe there's a bug where there's an odd pre-flash in manual mode?
But it makes no sense that it works with a Nikon flash in that cat-meow YouTube from Ben Evans (@ 7:10)

You Tube

geoffw · 12-12-2013, 02:05 PM

Originally posted by Steve.Ledger

Something is wrong then, on manual setting it should sync just fine like the other cams do. Maybe there's a bug where there's an odd pre-flash in manual mode?
But it makes no sense that it works with a Nikon flash in that cat-meow YouTube from Ben Evans (@ 7:10).

Yeah I thought manual mode would sort it. I will try the slow & trailing curtain sync when I get the time, to see if that makes ant difference.

Steve.Ledger · 12-12-2013, 03:25 PM

Doesn't. I tried that too

I must have shot over a hundred photos trying every conceivable configuration setting between flash and camera..

11-27-2013, 02:07 PM	#1
geoffw Senior Member Join Date: Feb 2013 Photos: Gallery Posts: 193	Flash sync Hi. Is there a reason anybody knows of why a remote flash, couple with a slave trigger, will not sync using the built in flash on a MX1 or a K200d. The flash fires ok but not in sync with the shutter judging from the result.

12-10-2013, 06:31 PM	#10
Steve.Ledger Veteran Member Join Date: Oct 2009 Location: Far North Qld Posts: 3,301	Originally posted by Tanzer But for mirrorless cameras like my Q and my X-90, the time between pre-flash and main flash is really fast, and only some of my triggers/flashes can keep up with them. I haven't tried my MX-1 yet -- maybe I will this weekend. What did you find? I can't get an optical slave to sync with the MX-1 Both flash, but only the camera flash is recorded. Last edited by Steve.Ledger; 12-10-2013 at 07:11 PM.

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11-27-2013, 02:20 PM	#2
jatrax Site Supporter Join Date: May 2010 Location: Washington Cascades Photos: Gallery \| Albums Posts: 12,991	Generally the remote flash with optical slave trigger goes off when the camera fires a pre-flash for P-TTL metering. And therefore that will not work. A remote flash has to be P-TTL compatible in order to function properly with optical triggering from the camera. The K-3 now has a manual flash mode that does not have a pre-flash and theoretically it should be possible for this to work in that mode, although I have not tried it yet. In your case the only option (assuming the remote is not P-TTL) is to use wireless radio triggers or a cable.

11-27-2013, 02:23 PM	#3
elliott Inactive Account Join Date: Dec 2008 Location: North Carolina Photos: Albums Posts: 1,720	What brand of optical triggers are you using? Some are able to ignore the P-TTL pre-flash, but many are not.

11-27-2013, 02:29 PM	#4
lister6520 Veteran Member Join Date: May 2012 Posts: 733	Is the slave trigger optical or radio? By optical I mean it triggers when it sees the light of the on camera flash. If so then it is a problem common to most cameras. The reason is that the camera will fire a 'pre-flash' before the actual exposure. It does this to measure how much power it will need to put into the flash for the actual exposure. Unfortunately the slave trigger will 'see' that pre-flash causing it to trigger before the shutter opens. Then when the camera fires the main flash burst the slave flash would be recharging its trigger circuit (and possibly the main capacitor) and would not be able to flash that second time when it is actually needed. There are solutions for this but they depend on the capabilites of the camera and the flash trigger. On the camera side what can sometimes be done is to set the onboard flash to manual exposure as with some cameras this disables the pre-flash which is causing the problem. Here I don;t mean manual exposure of the shutter but of the flash power. The other solution lies within the trigger. Some triggers 'know' about pre-flashes and have settings which allow them to ignore the pre-flash and only fire on the main flash. This is usually set by a very small slider switch on the trigger, or in the case of a flash with built in optical trigger it might even be a setting in the menu on the LCD. Sometimes there are two or even three choices of this setting, this because some cameras issue more than one pre-flash. You don;t really need to know how many flashes the camera produces and instead would just find by trial and error which one works best.

11-27-2013, 02:36 PM	#5
geoffw Senior Member Join Date: Feb 2013 Photos: Gallery Posts: 193 Original Poster	Thanks for your replies. Looks like the pre flash may be the issue. I'm using an old optical slave that I have to say I'm suprised it works and an old vivitar 283. I'm thinking I need to go shopping to get this sorted. Thanks again peeps.

11-27-2013, 02:59 PM	#6
Just1MoreDave Site Supporter Join Date: Feb 2007 Location: Aurora, CO Photos: Gallery \| Albums Posts: 6,340	If you are using a low flash power on the slave, you could try to use the 2 second delay (K200D has it, don't know about the MX1). When the delay is used, the preflash fires first, then the 2 second delay, then the main flash. So if your slave is ready to fire again in 2 seconds, it will work. The 12 second delay might work the same way.

11-27-2013, 03:32 PM	#7
JimJohnson Loyal Site Supporter Join Date: Jan 2012 Location: Summer:Lake Superior - Michigan Winter:Texas Hill Country Photos: Gallery Posts: 2,772	You want a Seagull SYK-5 optical slave for use with older flashes triggered by the built in flash- https://www.pentaxforums.com/forums/125-flashes-lighting-studio/187513-seagul...tructions.html You can purchase them for well under US$20.

11-27-2013, 04:13 PM	#8
Tanzer Veteran Member Join Date: Mar 2012 Location: Perrineville, NJ Posts: 1,375	If you set the Vivitar on one of the auto modes, it might work okay. Auto mode will limit the flash output, depending on the distance from flash to subject. Which will keep the capacitor charged and ready for the second flash. This works with all of my old flashes and my SLRs/DSLRs, because the time between pre-flash and main flash is kinda slow (due to mirror flipping up). But for mirrorless cameras like my Q and my X-90, the time between pre-flash and main flash is really fast, and only some of my triggers/flashes can keep up with them. I haven't tried my MX-1 yet -- maybe I will this weekend. By necessity, this method will only work if you are firing on less than 1/2 power, maybe less (which is why some old flashes have a single low-power setting, like 1/16). And auto mode at the flash's position might give you unpredictable results, looking at your scene from the camera's perspective. But it won't cost you anything to try it out. It should work on your K200d at least.

11-28-2013, 06:40 AM	#9
geoffw Senior Member Join Date: Feb 2013 Photos: Gallery Posts: 193 Original Poster	Thanks Dave Tanser & Jim. Good food for thought. Will try & have a play around at the weekend.

12-12-2013, 01:36 PM	#11
geoffw Senior Member Join Date: Feb 2013 Photos: Gallery Posts: 193 Original Poster	Tried to get the MX1 to sync but no joy. Given up for now.

12-12-2013, 01:37 PM	#12
geoffw Senior Member Join Date: Feb 2013 Photos: Gallery Posts: 193 Original Poster	Originally posted by Steve.Ledger What did you find? I can't get an optical slave to sync with the MX-1 Both flash, but only the camera flash is recorded. Same as that Steve.

12-12-2013, 02:05 PM	#14
geoffw Senior Member Join Date: Feb 2013 Photos: Gallery Posts: 193 Original Poster	Originally posted by Steve.Ledger Something is wrong then, on manual setting it should sync just fine like the other cams do. Maybe there's a bug where there's an odd pre-flash in manual mode? But it makes no sense that it works with a Nikon flash in that cat-meow YouTube from Ben Evans (@ 7:10). Yeah I thought manual mode would sort it. I will try the slow & trailing curtain sync when I get the time, to see if that makes ant difference.

12-12-2013, 03:25 PM	#15
Steve.Ledger Veteran Member Join Date: Oct 2009 Location: Far North Qld Posts: 3,301	Doesn't. I tried that too I must have shot over a hundred photos trying every conceivable configuration setting between flash and camera..