cxsparc? Sonia slave+RF603c flash trigger mods?

Started Mar 18, 2012 | Discussions
Shop cameras & lenses ▾
RussellInCincinnati Veteran Member • Posts: 3,201
cxsparc? Sonia slave+RF603c flash trigger mods?

cxsparc: http://forums.dpreview.com/forums/read.asp?forum=1042&message=40014425: I then modified the Yongnuo RF603C...added a wire from 3V battery power [Vin] to a 120 Kohm resistor and then to the connection J6 in the Yongnuo. The latter is required to configure the Yongnuo to be transmitter in spite of (obviously) not being mounted on top of a canon camera .-)

For my Nex 5, I just foolishly purchased 6 (!) Yongnuo RF-603n wireless flash transceivers, for $114 dollars, to trigger 5 remote slave flashes. Following John Bean's lead, one of the RF-603n's was to be put atop the Sonia digital slave unit (with programmable preflashes-ignored),

as the radio trigger for the other 5 RF-603n's...that are plugged into the 5 remote flashes and acting of course as flash radio-trigger receivers .

Understand from the great cxsparc and other posts now, that the RF-603n has no idea it's to be a transmitter when it's slid into an ordinary single-contact hot shoe. It's only gonna work right on a Nikon camera hot shoe. Wonderfully dense of me not to realize that sooner.

Anyway, am thinking that the post above means that the only thing needed to make an RF-603*C* (probably nearly identical to my RF-603n) work as a transmitter on an ordinary single-contact hot shoe, is to solder a 120000 ohm resister between the RF-603C's Vin contact and its J6 terminal, all inside the case, to provide the j6 contact with the "TTL wakeup signal". Am guessing that circuit will worst case drain about one milliAmp-hour per day of on-time from the 700 milliAmp-hour batteries.

But is that my only problem? In other words, if I modified an RF-603c and soldered in the resistor and wire described above, does anyone think it would then sit on top of the Sonia digital, become a transmitter, take a hotshoe trigger signal from the Sonia, and be triggered by it? Or do you think the Sonia is incapable of triggering the simplistically modified RF-603c "transmitter"? Cxsparc you appear to have understanding of the different kind of triggering methods, including the kind of trigger action provided by the Sonia and the kind of electrical maneuvers that constitute a flash trigger for the Yongnuo RF-603c. Thanks much in advance, anyone really.

It's a bad sign to me that the Sonia digital slave unit shown above does not seem to function as a direct trigger for the Yongnuo 560-II flash, either, when it is slid into the '560's hot shoe. Hmm, could the Yongnuo 560-II flash be made more responsive with the same simple modification as described above for the Yongnuo RF-603C trigger?

Am limping along now with the flashes operating at 1/4 power, as simple optical slaves to the little Nex 5 onboard flash. At that low power setting the flashes have no trouble flashing twice per shutter button press, triggering on both the Nex preflash, and the main flash.

cxsparc
cxsparc Veteran Member • Posts: 3,391
Re: cxsparc? Sonia slave+RF603c flash trigger mods?

RussellInCincinnati wrote:

cxsparc: http://forums.dpreview.com/forums/read.asp?forum=1042&message=40014425: I then modified the Yongnuo RF603C...added a wire from 3V battery power [Vin] to a 120 Kohm resistor and then to the connection J6 in the Yongnuo. The latter is required to configure the Yongnuo to be transmitter in spite of (obviously) not being mounted on top of a canon camera .-)

For my Nex 5, I just foolishly purchased 6 (!) Yongnuo RF-603n wireless flash transceivers, for $114 dollars, to trigger 5 remote slave flashes. Following John Bean's lead, one of the RF-603n's was to be put atop the Sonia digital slave unit (with programmable preflashes-ignored),

as the radio trigger for the other 5 RF-603n's...that are plugged into the 5 remote flashes and acting of course as flash radio-trigger receivers .

Understand from the great cxsparc and other posts now, that the RF-603n has no idea it's to be a transmitter when it's slid into an ordinary single-contact hot shoe. It's only gonna work right on a Nikon camera hot shoe. Wonderfully dense of me not to realize that sooner.

Let me straight away ask whether you have any possibility to return those 603 units? If so, I would recommend you to get the older 602 unit and 602 extra slaves. They do not require any modifications regarding the wakeup-signal, though they may have the same difficulty being triggered by optical slaves such as the sonia. So if you go the route of electrical modifications, you can as well keep the 603s.

Anyway, am thinking that the post above means that the only thing needed to make an RF-603*C* (probably nearly identical to my RF-603n) work as a transmitter on an ordinary single-contact hot shoe, is to solder a 120000 ohm resister between the RF-603C's Vin contact and its J6 terminal, all inside the case, to provide the j6 contact with the "TTL wakeup signal". Am guessing that circuit will worst case drain about one milliAmp-hour per day of on-time from the 700 milliAmp-hour batteries.

This should put the 603 into transmitter mode. You are correct that the battery drain is negligible. You can do this easily and test it while still disassembled, just put the battery into the 603 and check whther the led changes on transmitter and receiver.

But is that my only problem? In other words, if I modified an RF-603c and soldered in the resistor and wire described above, does anyone think it would then sit on top of the Sonia digital, become a transmitter, take a hotshoe trigger signal from the Sonia, and be triggered by it? Or do you think the Sonia is incapable of triggering the simplistically modified RF-603c "transmitter"? Cxsparc you appear to have understanding of the different kind of triggering methods, including the kind of trigger action provided by the Sonia and the kind of electrical maneuvers that constitute a flash trigger for the Yongnuo RF-603c. Thanks much in advance, anyone really.

Generally, this should work. However, as I have described in my post,

( http://forums.dpreview.com/forums/read.asp?forum=1042&message=40018885 ) I experienced difficulities triggering the 603 with my homegrown optical trigger unit. In my understanding, this way due to the very low switching voltage provided by the 603, failing to allow the thyristor of (most) optical slave units to switch through.

I have not disassembled any SOnia so do not know there internals. But if you post some pictures, I might be able to recommend whether you can modify it as easy as I did. Practically, it is just a cheap small-signal transistor and a resistor to be added.

It's a bad sign to me that the Sonia digital slave unit shown above does not seem to function as a direct trigger for the Yongnuo 560-II flash, either, when it is slid into the '560's hot shoe. Hmm, could the Yongnuo 560-II flash be made more responsive with the same simple modification as described above for the Yongnuo RF-603C trigger?

I do not know what you actually describe here. Do you mean that when you put the 560 ontop of the Sonia and trigger the sonia, the 560 does not flash? This should work without any modification! Remember to tighten the flash onto the socket to ensure good contact quality. Test with the Sonia set to No Preflash and check the flash directly visually whether its bulb lights up when you flash the camera flash of the Nex directly at the Sonia.

 cxsparc's gear list:cxsparc's gear list
Sony Alpha NEX-5N Sony a6000 Sony E 18-55mm F3.5-5.6 OSS Sony E 50mm F1.8 OSS Sony E 10-18mm F4 OSS +3 more
RussellInCincinnati OP Veteran Member • Posts: 3,201
What a great post, thanks, Sonia does trigger Yongnuo flash.

Russell: It's a bad sign to me that the Sonia digital slave unit shown above does not seem to function as a direct trigger for the Yongnuo 560-II flash, either, when it is slid into the '560's hot shoe

Cxsparc: Do you mean that when you put the 560 ontop of the Sonia and trigger the sonia, the 560 does not flash? This should work without any modification! Remember to tighten the flash onto the socket to ensure good contact quality. Test with the Sonia set to No Preflash and check the flash directly visually whether its bulb lights up when you flash the camera flash of the Nex directly at the Sonia.

Thanks Cxsparc, Sonia fixed! Well whatever was wrong, after doing what you said, at least the Sonia digital slave unit (e.bay number 370289332614) is indeed triggering a Yongnuo 560-II flash (that is plugged into the Sonia hot shoe) perfectly.

More responses to your helpful, detailed reply later. As for the problem of the Sonia triggering a Yongnuo RF-603n wireless trigger that expects a special wakeup signal, you are probably right that Yongnuo triggers. But am sorely tempted to attempt your modification to permanently provide one of them with the "TTL wakeup signal", so that it will work on any ordinary hot shoe as a transmitter.

Helios 58mm 44-2 lens at F/5.6. One should not pay a lot of money for one of these lenses, there are zillions of them. My 1972 "Zebra" copy has a handy "preset ring" that lets you focus wide open, then with a nudge stop down real quickly to the taking aperture. Am not enjoying this lens' resolution at the corners, at apertures wider than F/5.6. But Lightroom 4 fixes this lens' generous lateral color fringes nicely, 58mm is a nice APS-C focal length, the bokeh or blur is smoother than many a zoom lens, and it's pretty hard to take a fuzzy photo with a flash unit.

RussellInCincinnati OP Veteran Member • Posts: 3,201
step 1 great, easy to modify RF-603n to become transmitter

Cxsparc, your instructions for modifying the Yongnuo RF-603n wireless flash trigger transceiver , to make it configure itself permanently into a wireless flash trigger transmitter , worked great. When the modified RF-603n is turned on, not just the right-hand LED but the left-hand LED also lights up, signaling that it is a transmitter. And, when you press the "test" button on the transmitter, the right-hand LED flashes red as it should, and the receivers flash red in unison, etc.

And if I physically "short out" the central hot shoe contact on the bottom of the transmitter, bridge the big central contact with a metal screwdriver to the metal rails of the hot shoe, bingo, all the receivers immediately fire their attached Yongnuo flash units. Wunderbar.

Final step. It's always that last step that's a doozy. The Sonia Digital Slave unit

will not fire an RF-603n transmitter that is attached to the Sonia upper (trigger output) hot shoe. Even though the Sonia will fire a Yongnuo flash , when the bottom foot of the flash is attached to the top output hot shoe of the Sonia. Any ideas of a next step?

My guess is that the red wire in the picture above goes to the central hot shoe contact, and the blue wire goes to the outer metal rails of the hot shoe. While out and about, purchased a 2N3904 small signal transistor, and a 1000 ohm resistor, just in case.

Have studied your circuit diagrams, apparently

there is to be some kind of connection between the "emitter" of a transistor to somewhere near a capacitor and a resistor in parallel? With one of the main outer leads of the transistor going to Vin +, and the other lead going to Vin - ?

Hard to believe that you're helping us so much, thanks.

cxsparc
cxsparc Veteran Member • Posts: 3,391
Re: step 1 great, easy to modify RF-603n to become transmitter

Hi Russel,

I first was put off a little because this is an unmarked integrated circuit. But actually, you do not really need to bother with understanding that IC.

The solution is that red LED. If you have a multimeter, you can determine which cable goes where. For example, you could mount the flash onto the socket and measure where its trigger voltages comes in. Or beep it through which is not as reliable.

When you have then figured out which cable is Flash_Trigger+ and FlashTrigger-, you can then measure the voltage at both ends of the red LED.

there is to be some kind of connection between the "emitter" of a transistor to somewhere near a capacitor and a resistor in parallel? With one of the main outer leads of the transistor going to Vin +, and the other lead going to Vin - ?

1. It is not the emitter (E) but the base (B) which is the input for the transistor. This transistor switches when a positive voltage is applied to its base, compared to the voltage applied at trigger- (= Emitter)

2. Most probably you don't have to connect to Vin+ or - (which are to my understanding battery power) whereas in my schematic Trigger+ and Trigger- of course have to be connected.

So you connect the tranistors collector and emitter as shown, connect the resistor to the base of the transistor and then have to search for a positive voltage in the moment where the Sonia attempts to trigger the flash.

I assume that the red LED flashes when the Sonia tries to trigger, right?

In my schematic, the LED also flashes. It is connected to ground, so a positive voltage is applied to it in that moment. Use the multimeter and try to measure if there is a constant voltage at either end of the LED when it is inactive (measured against battery ground). If so, the logic is inverse and the LED is connected to a constant positive voltage and turned on by grounding the other end (you could handle that by replacing the transistor with a PNP type, but it might be difficult).

If on the other hand, there is no significant voltage at either end of the LED when it is inactive, but a short burst of positive voltage when it flashes, you then can connect the other end of the resistor to that LED (the side with the higher voltage).
That should be it.

On last idea which came to my mind if this does not work for you, I'll tell you in that case.

 cxsparc's gear list:cxsparc's gear list
Sony Alpha NEX-5N Sony a6000 Sony E 18-55mm F3.5-5.6 OSS Sony E 50mm F1.8 OSS Sony E 10-18mm F4 OSS +3 more
RussellInCincinnati OP Veteran Member • Posts: 3,201
come to think of it, the LED does flash when Sonia triggers

Cxsparc: ...that red LED. If you have a multimeter, you can determine which cable goes where. For example, you could mount the flash onto the socket and measure where its trigger voltages comes in.

Think you are telling me to put the Yongnuo 560-II flash into the hot shoe of the Sonia Digital Slave Unit, and turn the flash on. But the Sonia unit should be turned off during this test? Anyway you think that as long as the flash is "on", a voltage will appear between the 2 wires connected to the hot shoe, and then we can measure that voltage and deduce which wire is "+" and which wire is "minus". By the way sort of hope the red wire is "+" and the blue one is "minus", just for sanity's sake.

Cxsparc: When you have then figured out which cable is Flash_Trigger+ and FlashTrigger-,

Then can connect the "emitter", the wire coming from the NPN transistor case (that is sketched with a little arrowhead in the datasheet packaged with the $1.2 dollar transistor), to the "Trigger-" wire going to the hot shoe. Then connect the "collector", the wire coming from the transistor case that has no arrowhead associated with it on the transistor's datasheet, to the "Trigger+" wire.

Cxsparc: ...and then have to search for a positive voltage in the moment where the Sonia attempts to trigger the flash. I assume that the red LED flashes when the Sonia tries to trigger, right?

Yes. Can't swear exactly when the LED flashes, but it certainly flashes at about the time the Sonia is triggering something

Cxsparc: In my schematic, the LED also flashes. It is connected to ground, so [in my circuit shown in a previous post in this thread] a positive voltage is applied to it in that moment. Use a voltmeter and try to measure if there is a constant voltage at either end of the LED when it is inactive (measured against battery ground). If so, the logic is inverse and the LED is connected to a constant positive voltage and turned on by grounding the other end (you could handle that by replacing the transistor with a PNP type, but it might be difficult).

If on the other hand, there is no significant voltage at either end of the LED when it is inactive, but a short burst of positive voltage when it flashes, you then can connect the free end of the 1000 ohm resistor [that you have soldered to the transistor's middle "base" wire] to that LED (the side with the higher voltage).

So if am maximum lucky, there will be no voltage between the battery minus and either end of the LED, while the slave is inactive. Then, at the moment the slave triggers, a brief positive voltage will appear at one or the other end of the LED. The end where the positive voltage appears is the end that I connect through a 1000 ohm resistor to the "middle wire" coming from the our new transistor. And then the now super-transistorized Sonia optical slave (that can ignore Sony Nex 5 pre-flashes) may be able to trigger a slightly modified Yongnuo RF-603n or RF-603c wireless radio trigger/transmitter.

Will go get a voltmeter tomorrow. Am supposing the ideal voltmeter would be one of those "latching" circuit probes that can light up if they encounter a brief positive voltage pulse?

If by bad luck there is a constant voltage at either end of the LED while the unit is on but inactive, will write you back and ask for a bit more clarification as to how to employ a PNP transistor so as to accomplish the "inverted logic" that is called for.

Thanks as usual, to be continued within about 12 hours. Hope am interpreting your instructions correctly.

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Here's an example of my attempt to use the Alpha 18-55 kit zoom, which at 55mm does not have quite the sharpness of my best prime lenses (even at F8), and doesn't have great bokeh either...but when all other conditions are right it doesn't stand in the way of a nice close portrait (where you end up having to do a bit of facial blurring anyway). But learned my lesson, it's back to the Canon FDn 50/1.4 from now on if 50mm's OK.

Actually the humble 1972 Russian 58mm Helios 44-2 at F5.6 is better than the Alpha zoom for a close portrait.

cxsparc
cxsparc Veteran Member • Posts: 3,391
Re: come to think of it, the LED does flash when Sonia triggers

Sounds like you understand it Best luck!

BTW, why do you shoot your portraits with such low shutter speeds? Even if you use a tripod, it is bound to get unsharp due to subject movement? Or did you flash at the same time?

 cxsparc's gear list:cxsparc's gear list
Sony Alpha NEX-5N Sony a6000 Sony E 18-55mm F3.5-5.6 OSS Sony E 50mm F1.8 OSS Sony E 10-18mm F4 OSS +3 more
RussellInCincinnati OP Veteran Member • Posts: 3,201
amazing, your circuitry suggestions worked immediately
1

Success. Following forum member Cxsparc's instructions, a $16 dollar Sonia Digital Slave Unit

http://www.ebay.com/itm/NEW-PROGRAMMABLE-REMOTE-SLAVE-NO-Preflash-Triggering-/370289332614?pt=Camera_Flash_Accessories&hash=item5636f6d186#ht_1000wt_1393

can, if modified by adding a transistor and resistor inside its case, activate through its hot shoe a Yongnuo RF-603c or RF-603n wireless flash trigger.

For this to work, the Yongnuo radio transceiver that is slid into the top of the Sonia Digital Slave, must itself have a resistor added inside its case, in order that it configure itself as a transmitter. Unmodified Yongnuo radio transceivers, plugged into remote flash units within 50 meters or so, will automatically react as receivers to signals from the modified transceiver. Too bad that the inexpensive Sonia digital slave unit doesn't supply a special "TTL wakeup signal" through its hot shoe, to make an attached Yongnuo transceiver automatically realize it should be a transmitter. That's OK, we can rewire the Yongnuo to permanently be in transmitter mode.

The modification necessary to the Yongnuo transceiver to make it a transmitter, is to add a tiny 20 cent (Radio Shack sells 5 for about a dollar) 1/8th watt resistor of about 120000 ohms, connecting (i.e. soldering) one end of the resistor to the "J6" contact inside the Yongnuo disassembled casing. The other end of the resistor is easily soldered/connected to the Vin battery power terminal on the Yongnuo exposed circuit board. Make sure to cover the bare resistor leads with a bit of electrical tape or heat shrink tubing to make sure the bare leads don't touch anything inside the case after reassembly. The resistor is so small that the casing will easily reassemble.

A modified transceiver will, when turned on, always light up both its green LEDs full time, showing that it is functioning as a flash-signal transmitter. In contrast, unmodified Yongnuo transceivers that are not in the presence of a transmitter will automatically power up with a single green LED lit, showing they are receivers. Actually unmodified transceivers will automatically power up with both LEDs glowing green, if they are turned on while in range of the active transmitter. The receivers' second LED being lit shows that they are in good radio contact with a transmitter. Then press the "test" button on the powered-up transmitter, and nearby, active receiver LEDs will flash red, and whatever flashes are plugged into those receivers will fire.

The modification necessary to the Sonia Digital Slave Unit, it make it capable of firing the ultra modern Yongnuo wireless radio triggers, is to open it up and connect/solder in a transistor and resistor. The transistor is a BC550 or 2N3904. My 2N3904 came from Radio Shack for $1.19 (buy two in case you mess up the first one). The 1000 ohm, 1/8th watt resistor is also from Radio Shack, again about 1 dollar for 5. You should of course have a grounded 15 watt soldering iron, and thin rosin core solder, at the ready.

The "emitter" wire of the tiny transistor must be connected\soldered to some bare metal place on the blue wire inside the Sonia case. The "collector" wire of the tiny 3-wire transistor is connected to the red wire inside the Sonia case. The middle "base" wire of the transistor is connected to one end of the 1000 ohm resistor, then the other wire from the resistor is in turn soldered to the bare "left-hand" wire of the red LED. The red LED wire is "on the left" if you are looking down at the circuit board in your hands, with the red LED pointing towards your chest.

When the bare wires are wrapped in a bit of insulating tape and the Sonia case is reassembled, the red LED on the Sonia case will no longer light up under any conditions. But that's OK, because surprisingly, when you slide the Yongnuo RF-603x transceiver into the Sonia hot show and turn the Yongnuo on, one of the Yongnuo LEDs lights up whenever the Sonia LED would have lit up. That is to say, the Yongnuo red LED duplicates the Sonia's LED behavior whenever it's attached to the Sonia's output hot shoe, making it OK that our transistor modification snuffed out the Sonia's internal LED.

And that's it for the modifications. To use, turn on the Sonia digital slave unit, and press the "Program" button to the down position, and fire the Nex 5's preflash-plus-flash towards the Sonia black optical sensor. Then push the Program button again on the Sonia, it will spring back up to the "up position". Now you can turn the Sonia off with its switch and wait a 10 seconds. Now the Sonia has been programmed to "remember" the Nex pre-flash pattern.

Then attach a modified-to-be-transmitter $20 dollar Yongnuo RF-603c or -n radio transmitter into the Sonia hot shoe. With both the Sonia and the Yongnuo turned on, you are armed and ready. The Nex 5 flash, when fired, will activate the Sonia digital slave unit only on the final flash, which will in turn activate the Yongnuo transmitter, which will in turn fire any number of Yongnuo RF-603x transceivers (and their attached flashes) that are "listening" in the area. Of course if the flashes being fired have built-in optical slaves, their optical slave functions must be turned off, because you are intending that those flashes only fire when they are attached to Yongnuo transceivers( that are acting as flash trigger receivers).

But how do you have the Sonia digital slave unit "see" the Nex 5 flash, but not have the Nex 5 flash "show up" in the picture? I have found it adequate to go into the Sony menu, under brightness, and turn the flash fill EV setting to -2, the minimum, making it quite weak. I also have taped a bit of aluminum foil over the flash, so that the flash only illuminates "upward" instead of forward. One can even put a balloon over both Nex flash and slave triggers so that only the triggers see the flash.

RussellInCincinnati OP Veteran Member • Posts: 3,201
outdoor photography after sunset=slow shutter speeds

Cxsparc: By the way, why do you shoot your portraits with such low shutter speeds? Even if you use a tripod, it is bound to get unsharp due to subject movement? Or did you flash at the same time?

Sure, would have loved to use a camera with the same image quality at ISO 6400 as the Nex has at ISO 800 (if that camera was about as small and light as the Nex, and worked with my favored lens mounts, etc...Fuji X-Pro 1 JPEGs?). Then the picture taken below, after sunset , at 1/6th second exposure time, could have been taken at a less anxiety-inducing 1/50th of a second. After sunset the light gets so soft, and the brightest glow from the sky is down low. Which so nicely illuminates what might have been otherwise slightly grimmer, darker eye sockets.

And would not say that, as long as you use a tripod, you are "bound" to get unsharp photos due to subject movement even at 1/4 second exposure. For example, this photo, one of maybe 3 exposures, is not particularly blurry, quite the opposite. Except for the cloth "flower" that is moving in the wind. Really with a tripod and cooperative subjects, 1/8th of a second is a breeze and 1/4 of a second isn't terrible. Enough light for 1/10th of a second, and you can do a large group of people.

A tripod hugely expands the range of natural lighting situations you can use and still get beautifully clear photos.

cxsparc
cxsparc Veteran Member • Posts: 3,391
Re: amazing, your circuitry suggestions worked immediately

Great that you gave extensive feedback so others might, with a little optimism also get radio triggered flash for their Nex's!

 cxsparc's gear list:cxsparc's gear list
Sony Alpha NEX-5N Sony a6000 Sony E 18-55mm F3.5-5.6 OSS Sony E 50mm F1.8 OSS Sony E 10-18mm F4 OSS +3 more
cxsparc
cxsparc Veteran Member • Posts: 3,391
Re: outdoor photography after sunset=slow shutter speeds

I was only surprised that this works, but as you stated, the clue is "cooperative subjects" :-).

I'd guess that with a flash diffusor or umbrella, flash turned quite low and long shutter speeds one could both freeze the subject and still capture the ambient lighting. But then, I am not much of a strobist yet.

 cxsparc's gear list:cxsparc's gear list
Sony Alpha NEX-5N Sony a6000 Sony E 18-55mm F3.5-5.6 OSS Sony E 50mm F1.8 OSS Sony E 10-18mm F4 OSS +3 more
Smiert Spionam Contributing Member • Posts: 547
Re: outdoor photography after sunset=slow shutter speeds

Bouncing this back up -- your RF603 mod works great! I don't have the extra complication of needing to rig up an optical trigger for the 5/5n, because I've got a 7. I used a Radio Shack 100k 1/4 watt resistor, because it was the closest they had, and I didn't want to wait to order something closer. Still, 20% is probably fine -- and in any case, it works.

With a Pixel TF-325 hot shoe adapter, I can use an RF-603 to trigger my remote flashes with the NEX-7, with no optical triggers necessary.

As a side benefit, I can also use the modified RF-603 as a handheld trigger to trip my flashes while metering, which is nice to be able to do without taking a shot with the camera.

Thanks!

RussellInCincinnati OP Veteran Member • Posts: 3,201
cxsparc's RF-603 mod, so Nex 7 needs no optical trigger?

Smiert: [cxsparc's] RF603 mod works great! I don't have the extra complication of needing to rig up an optical trigger for the 5/5n, because I've got a 7...With a Pixel TF-325 hot shoe adapter, I can use a Yongnuo RF-603 [transceiver, rigged as permanent transmitter] to trigger my remote flashes with the NEX-7, with no optical triggers necessary.

I see, the Nex 7 has a standard-enough flash socket that you are able to plug a Pixel TF-325 hot shoe adapter into it. The Pixel unit then, in turn, apparently provides a fairly standard "hot shoe", that the RF-603 flash transceiver can slip into. Now normally the standard "hot shoe" on the Pixel would not have enough features to make an RF-603c transceiver configure itself as a transmitter. But with the adding-a-resistor cxsparc modification to one of your RF-603's, that modified RF-603 is permanently self-configured into transmitter mode. Slip the modified RF-603 transceiver into the Pixel hot shoe, and bingo, you have a wireless flash transmitter.

Then you put unmodified RF-603's onto the bottom of each flash you want to be remotely triggered by your Nex 7, and you're in business. In the presence of the RF-603 transmitter, all the rest of the RF-603's in the house automagically configure themselves as receivers.

All this without having to jigger up a modified Sonia pre-flash-ignoring optical slave unit, to crudely attach to a Nex 3 or 5's little flash. A nice advantage of Nex 7.

I also assume that if you were willing to go all Sony, there are Sony wireless flashes that could plug into the Nex 7 as a transmitter, and also serve as "receiving" slave flashes from the master Sony flash on the Nex 7? But you and I have no need for those proprietary wireless systems, because we've figured out how to set off even totally manual flashes with the Yongnuo RF-603 flash transceivers.

Smiert: I used a Radio Shack 100k 1/4 watt resistor, because it was the closest they had, and I didn't want to wait to order something closer.

Of course, when someone calls for a 120k ohm resistor, unless it's a fairly precise circuit, a 100K resistor will work fine. As you've verified, nice. In this case it's a certainly imprecise circuit, because all the resistor is doing is feeding a tiny "wakeup" current from the Yongnuo RF-603 battery to some other part of the Yongnuo...that is looking to be plugged into a Canon hot shoe that would normally supply those little microamperes of electricity. Cxsparc called for a 120K ohm resistor to supply maybe 25 microAmps of current, while your 100k resistor probably supplies around 30 microAmps of current, a trivial difference for all parties.

Smiert: As a side benefit, I can also use the modified RF-603 as a handheld trigger to trip my flashes while metering, which is nice to be able to do without taking a shot with the camera.

Absolutely, of course a nice and standard feature of radio triggers, the transmitter has a "test" button on it.

You and I are both apparently attracted to the ultra-modern, minimalist Yongnuo RF-603 radio triggers that take standard AAA batteries and have super great range. They don't have the multi-channel feature of more sophisticated triggers.

But at least they can be configured for more than one channel...Some primitive goofing around is then possible, whereby you have some slave triggers on channel #1, other triggers on channel #2, and you fire whichever bank of triggers you want by switching the transmitter channel to #1 or #2.

Thanks again cxsparc.

Smiert Spionam Contributing Member • Posts: 547
Re: cxsparc's RF-603 mod, so Nex 7 needs no optical trigger?

Yes, that pretty well describes it. A couple of small things:

The test button on a standard RF-603 will only trigger the other units if it's designated as the transmitter, which only happens when it's connected to a compatible camera (Nikon or Canon, generally). With the mod, I can use the 603 as a trigger completely independent of the camera.

The NEX-7 doesn't recognize that you're using flash, so it will continue to adjust the gain of the LCD to approximate the likely exposure. This means that if (for example) the correct exposure of a scene would be 1/15s @ f/4 but you set the camera manually to 1/125s @ f/4, the display will look three stops underexposed. No big deal on a tripod or for fill flash, but handheld in low light, this could be irritating. There may be a menu setting to change the way the display works in this situation -- I'll have to poke around a little.

RussellInCincinnati OP Veteran Member • Posts: 3,201
what's the smallest Sony flash that works with Nex 7?

Smiert: The NEX-7 doesn't recognize that you're using flash, so it will continue to adjust the gain of the LCD to approximate the likely exposure...handheld in low light, this could be irritating. There may be a menu setting to change the way the display works in this situation -- I'll have to poke around a little.

Would enjoy hearing if you get this figured out. Isn't there indeed some kind of menu option for this situation?

Hmm, also what is the absolute smallest external flash that you could use on the Nex 7, that would tell the camera to put itself into the always-bright-preview mode?

Ironically there is no possible issue of this with the Nex 3/5, because we have to use the little external flash to make a flash work at all anyway. So the camera always knows to provide a bright preview.

cxsparc
cxsparc Veteran Member • Posts: 3,391
Re: cxsparc's RF-603 mod, so Nex 7 needs no optical trigger?

You are all welcome, it is always nice to get positive feeback after having contributed something into the internet void

The standard battery size of the 603 was for me the deciding factor to keep them and modify them to make them usable for the Nex 5N.

 cxsparc's gear list:cxsparc's gear list
Sony Alpha NEX-5N Sony a6000 Sony E 18-55mm F3.5-5.6 OSS Sony E 50mm F1.8 OSS Sony E 10-18mm F4 OSS +3 more
Smiert Spionam Contributing Member • Posts: 547
Re: cxsparc's RF-603 mod, so Nex 7 needs no optical trigger?

Much appreciated, cxsparc! Very glad I found your posts.

I really like the AAA battery solution, too -- gave me confidence about ready access to spares, and I always have extras from my Eneloop packs.

I haven't solved the dim viewfinder on the NEX-7 yet, though I haven't really dug into the menus. I know I can work around it by switching exposure mode (S or M for the actual exposure, switching to A so that the camera will automatically compensate the shutter speed to give a bright viewfinder), and I can probably assign that to a dial for quick changes. Still, it would be nice to avoid having to do that.

Smiert Spionam Contributing Member • Posts: 547
Re: what's the smallest Sony flash that works with Nex 7?

Got it (with a tip from douglasf13):

Setup--> Live View Display--> Setting Effect OFF.

Perfect.

RussellInCincinnati OP Veteran Member • Posts: 3,201
or just buy Seagull SYK-5 and CR-301 wireless triggers

After a bit more research, instead of modifying the Sonia optical trigger, and modifying a Yongnuo RF-603c transceiver to work with the Sonia as a transmitter, I agree with the advice given me earlier, in that maybe it makes more sense to buy a Seagull SYK-5 optical slave that will, without modification, trigger the older Yongnuo CTR-301P type radio transmitter/receiver pairs.

It's easy to find the Seagull SYK-5 optical slave which is real inexpensive. And there are lots of clues all over the web that the Seagull works with the Nex:
http://www.amazon.com/review/R2M04CZPHEH3U9

And here's a super inexpensive version of the Yongnuo CTR-301p type radio transmitter/receiver pair. It's called the Nicna CR-301, and each radio transmitter/receiver pair is just about $15 U.S. dollars:

http://www.ebay.com/itm/CTR-301P-Wireless-Studio-Flash-Trigger-Set-With-PC-Port-/320462975649

This is cheaper than buying and modifying a newer model Yongnuo RF-603c radio transceiver. Specifically the Yongnuo RF-603c transceivers are about $20 dollars apiece. For $15 dollars Nicna gets you an older-style CTR-301P type transmitter and receiver both. So if you want to trigger 5 slave flashes, just pay $75 and you'll end up with 5 receivers, 1 transmitter, plus 4 spare transmitters.

Are there any advantages to the Yongnuo RF-603c setup? Well the newer style takes standard AAA rechargeable batteries, that's nice. And the range is probably a lot longer, 200 feet or something. But if I had to do the whole thing over again, I think I'd go the Seagull plus Yongnuo CTR-301p's, or the off-brand version called CR-301. Those units have plenty of range for normal setups, and the batteries don't cost an arm and a leg on amazon or whatever.

The not-too-colossal package they make rubber-banded to the Nex flash:
http://www.karaatanasov.info/

Bokehmon Trainer Regular Member • Posts: 100
Re: cxsparc? Sonia slave+RF603c flash trigger mods?

I used a 100k resistor and connected the UIN to J6.. it works when I click on the button, but when I attach it to the hotshoe, it gets disconencted and only one light works.. does anyone happen to know why this happens?

Thanks.

Keyboard shortcuts:
FForum MMy threads