Will the flash AF240Z work with the Kx?

The Kurly One · 04-05-2010, 03:03 PM

I've found several threads but none are specific to the Kx. Will it work?
What modes?
I guess I can just set it manually right and it should work fine as a bounce flash?

It takes 4 AA batteries so I guess its right on at 6 volts...

**Just1MoreDave** · 04-05-2010, 04:13 PM

It should be safe to use. On the flash, P mode probably doesn't work, A mode will use the flash's sensor to cut power when it thinks there is enough light, and M mode will fire at full power. The zoom head is labeled in film terms, so on the K-x it is really 24mm to 90mm. If you use a lens in that range, set the head right, use A mode on the flash and M mode on the camera with the recommended settings on the back of the flash, it should work fine. You should at least get a flash output that's close enough to adjust to the correct settings.

The Kurly One · 04-05-2010, 04:15 PM

Another quick question in regards to it. When are the right times to use the hotshoe flash as opposed to the cameras basic flash?

**Just1MoreDave** · 04-05-2010, 06:35 PM

The AF240Z is about twice as powerful as the on-camera flash, depending on where the head is. Moving the light source up helps clear some bulkier lenses and reduces redeye. You can't bounce the popup flash either.

The popup flash will always have working batteries, can't be forgotten, is free and completely compatible.

sterretje · 04-06-2010, 12:57 AM

Originally posted by The Kurly One

It takes 4 AA batteries so I guess its right on at 6 volts...

I think you're referring to the trigger voltage. In that case, there is NO relationship between the battery voltage and the trigger voltage. And therefore it is not guaranteed that it is safe.

According to Photo Strobe Trigger Voltages, the trigger voltage of the AF240z is 4.8V

The Kurly One · 04-06-2010, 02:29 AM

The article you linked me to says its safe.... now I'm confused...

sterretje · 04-06-2010, 03:07 AM

Sorry, that was not the intention. 4.8V should be safe.

Only point I was trying to make is that battery voltage has nothing to do with trigger voltage. And you can draw your own conclusions from the link

gebco · 04-07-2010, 06:37 PM

One of the reasons I got my Sony V3 years ago was for external flash capability with the hotshoe. I already had the AF240Z and wanted to try it out but was also concerned about the trigger voltage so I checked out botzilla.com. It worked fine and I used it for several weeks until I got a dedicated flash unit.

Using it on my K-x, I find it works best in P mode. In using it with both my Sony and now my K-x, there has never been a problem.

noblepa · 04-08-2010, 11:13 AM

Originally posted by sterretje

Sorry, that was not the intention. 4.8V should be safe.

Only point I was trying to make is that battery voltage has nothing to do with trigger voltage. And you can draw your own conclusions from the link

Case in point: I have an old Vivitar 283. It also uses four AA batteries, yet the trigger voltage is about 125 volts. I've heard of some of them that have trigger voltages of more than 300 volts. The 283 was in production so long, that it was made in several different places, and had somewhat different internal design and circuitry. Hence the difference.

Electronic flashes all use an oscillator to step the battery voltage up to a very high voltage, internally. Usually they operate at several hundred volts. The oscillator is the whine you hear as they recharge. This high voltage is used to charge a capacitor. In its simplest form, the flash synch just forms the path between the capacitor and the flash tube. When the shutter is tripped, the camera acts like a switch and connects the two terminals of the synch, allowing the capacitor to discharge through the flashtube. Additional circuitry is required to act as a relay and pass only a low voltage to the camera.

04-05-2010, 03:03 PM	#1
The Kurly One Senior Member Join Date: Jan 2010 Photos: Gallery Posts: 233	Will the flash AF240Z work with the Kx? I've found several threads but none are specific to the Kx. Will it work? What modes? I guess I can just set it manually right and it should work fine as a bounce flash? It takes 4 AA batteries so I guess its right on at 6 volts...

04-07-2010, 06:37 PM	#8
gebco Veteran Member Join Date: Mar 2010 Location: Winnipeg Photos: Gallery \| Albums Posts: 329	I used it on my Sony V3 One of the reasons I got my Sony V3 years ago was for external flash capability with the hotshoe. I already had the AF240Z and wanted to try it out but was also concerned about the trigger voltage so I checked out botzilla.com. It worked fine and I used it for several weeks until I got a dedicated flash unit. Using it on my K-x, I find it works best in P mode. In using it with both my Sony and now my K-x, there has never been a problem.

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04-05-2010, 04:13 PM	#2
Just1MoreDave Site Supporter Join Date: Feb 2007 Location: Aurora, CO Photos: Gallery \| Albums Posts: 6,340	It should be safe to use. On the flash, P mode probably doesn't work, A mode will use the flash's sensor to cut power when it thinks there is enough light, and M mode will fire at full power. The zoom head is labeled in film terms, so on the K-x it is really 24mm to 90mm. If you use a lens in that range, set the head right, use A mode on the flash and M mode on the camera with the recommended settings on the back of the flash, it should work fine. You should at least get a flash output that's close enough to adjust to the correct settings.

04-05-2010, 04:15 PM	#3
The Kurly One Senior Member Join Date: Jan 2010 Photos: Gallery Posts: 233 Original Poster	Another quick question in regards to it. When are the right times to use the hotshoe flash as opposed to the cameras basic flash?

04-05-2010, 06:35 PM	#4
Just1MoreDave Site Supporter Join Date: Feb 2007 Location: Aurora, CO Photos: Gallery \| Albums Posts: 6,340	The AF240Z is about twice as powerful as the on-camera flash, depending on where the head is. Moving the light source up helps clear some bulkier lenses and reduces redeye. You can't bounce the popup flash either. The popup flash will always have working batteries, can't be forgotten, is free and completely compatible.

04-06-2010, 12:57 AM	#5
sterretje Veteran Member Join Date: Dec 2008 Location: Roodepoort, South Africa Photos: Gallery \| Albums Posts: 3,561	Originally posted by The Kurly One It takes 4 AA batteries so I guess its right on at 6 volts... I think you're referring to the trigger voltage. In that case, there is NO relationship between the battery voltage and the trigger voltage. And therefore it is not guaranteed that it is safe. According to Photo Strobe Trigger Voltages, the trigger voltage of the AF240z is 4.8V

04-06-2010, 02:29 AM	#6
The Kurly One Senior Member Join Date: Jan 2010 Photos: Gallery Posts: 233 Original Poster	The article you linked me to says its safe.... now I'm confused...

04-06-2010, 03:07 AM	#7
sterretje Veteran Member Join Date: Dec 2008 Location: Roodepoort, South Africa Photos: Gallery \| Albums Posts: 3,561	Sorry, that was not the intention. 4.8V should be safe. Only point I was trying to make is that battery voltage has nothing to do with trigger voltage. And you can draw your own conclusions from the link

04-08-2010, 11:13 AM	#9
noblepa Veteran Member Join Date: Sep 2007 Location: Bay Village, Ohio USA Posts: 1,142	Originally posted by sterretje Sorry, that was not the intention. 4.8V should be safe. Only point I was trying to make is that battery voltage has nothing to do with trigger voltage. And you can draw your own conclusions from the link Case in point: I have an old Vivitar 283. It also uses four AA batteries, yet the trigger voltage is about 125 volts. I've heard of some of them that have trigger voltages of more than 300 volts. The 283 was in production so long, that it was made in several different places, and had somewhat different internal design and circuitry. Hence the difference. Electronic flashes all use an oscillator to step the battery voltage up to a very high voltage, internally. Usually they operate at several hundred volts. The oscillator is the whine you hear as they recharge. This high voltage is used to charge a capacitor. In its simplest form, the flash synch just forms the path between the capacitor and the flash tube. When the shutter is tripped, the camera acts like a switch and connects the two terminals of the synch, allowing the capacitor to discharge through the flashtube. Additional circuitry is required to act as a relay and pass only a low voltage to the camera.