Microflash to fire optical strobes without using camera's flash

[blueglass 3]

Hi,

I have made this tiny flash that allows firing optical strobes without using the camera's flash, avoiding the annoying camera delay caused by the internal flash recycling when shooting fast action, even at 1/128 power.

It can be turned on and off inside the Nauticam D7000 housing using the flash down lever, so it's easy to turn off both strobes from the housing to shoot ambient light or to make PRE-white balance.

 

 

You can get an idea of how it works in this video (in Spanish, but you can hear the shooting speed)

 

http://vimeo.com/28090025

 

I'll be testing it next week with white sharks, where I hope to find some action that needs fast shooting.

[DerekB 2]

Looking forward to hearing how it works! I just adapted my surf housing to fire F/O slaves. I might en up needing something like this

[cor 0]

I haven't used my D7000 much yet, but is the delay on 1/128th generally more than the recycle time of your UW strobes?

[bvanant 191]

I haven't used my D7000 much yet, but is the delay on 1/128th generally more than the recycle time of your UW strobes?

Certainly not on the 7D. In ttl mode I wait a bit sometimes for the camera. In manual at 1/128 power I wait only for the Inon/S&S.

Bill

[tdpriest 115]

... is the delay on 1/128th generally more than the recycle time of your UW strobes?

 

But that's not as much fun as building your own gadget!

 

Tim

 

[bvanant 191]

But that's not as much fun as building your own gadget!

 

Tim

 

I would love to build one if I could get hold of a circuit diagram that makes sense to a chemist's brain.

Bill

[cor 0]

Im interested in the answer though. I have a D7000 and am wondering if at 1/128th power you'll ever have a problem where your main strobes are ready but your D7000 isnt. Otherwise I see no reason to have such a gadget, even though I agree making gadgets is cool It only makes sense in manual (Non-ttl) mode anyways, and in manual mode 1/128th is all you need.

[Drew 0]

Actually something like this would be awesome for the people who need high fps with strobes. Zillion has something similar.

My Hartenberger 250 strobes can easily hit 10 fps at 1/32 power (it recycles from 1/64 in 0.06 sec). With fast action stuff like baitballs, it'd be awesome to have something like this, especially if it can sync at higher shutter speed than X-sync.

With the new cameras hitting 12fps, this would be a nice addition to non-hardwired strobe firing.

[blueglass 3]

I haven't used my D7000 much yet, but is the delay on 1/128th generally more than the recycle time of your UW strobes?

 

If you wat a few seconds between shots you will never noticed any delay, but try to shoot 5-6 photos with about once second interval and you will notice that the camera stops working for a loooong time. You can see it in the video link I posted, in which the camera is set to 1/128.

 

If you shoot the underwater strobes at full and you wait for them to recycle totally (about 1.5 sec) you will not feel any delays.

But when shooting fastt action with powered down strobes the delay can last for 10-15 seconds

 

With this thingie i can shoot 6 fps continuously with Inon S2000 strobes set at -2.

 

Used with the D7000 you can use 1/400 and you barely see the second curtain at the bottom of the frame. If you go faster than that you will see it very clearly and you would have to pay attention in composition not to place anything you want flash on at the bottom of the frame.

 

More in few days when I come back foam Guadalupe....

[blueglass 3]

If you wait a few seconds between shots you will never notice any delay, but try to shoot 5-6 photos with less than one second interval and you will notice that the camera stops working for a loooong time. You can see it in the video link I posted, in which the camera is set to 1/128 flash power.

 

If you shoot the underwater strobes at full and you wait for them to recycle totally (about 1.5 sec) you will not feel any delays.

But when shooting fast action with powered down strobes the camera delay can last for 10-15 seconds

 

With this thingie I can shoot 6 fps continuously with Inon S2000 strobes set at -2.

 

With the D7000 you can use 1/400 and you barely see the second curtain at the bottom of the frame. If you go faster than that you will see it very clearly and you would have to pay attention to composition not to place anything you want flash on at the bottom of the frame.

 

More in few days when I come back foam Guadalupe....

[JohnLiddiard 31]

Build the circuit into a replacement for a cable bulkhead socket. That way you can convert a housing that does not have room for popup flash or any optical sockets to use fibreoptics instead of cables. Does it also mimic digital TTL? Or just manual?

[cor 0]

I see what you're saying. Same thing on my D7000. After about 10 shots at 1/128th it's very slow to recharge. Very cool solution. Would you share your design? Should be quite simple to make. I may have to look into doing this as well.

[davichin 18]

This is also a great idea for those weird people that buy cameras without flash like the 5DmkII... Now, all those will be able to shoot strobes optically...

[cor 0]

You still need a way to get the light outside the housing.

[davichin 18]

There are many connectors that allow for that... Hugy or Nauticam come to mind, but for sure there are more...

[rtrski 20]

You still need a way to get the light outside the housing.

 

Well, unless you have an Ikelite housing. Then you just have to shield it so that the microflash doesn't generate backscatter in the frame. The new 1/4-20 top-mount threading position on the DSLR housing upgrade is the perfect place to mount a simple block of some sort that accepts your fiberoptics, assuming the microflash is located inside the housing beneath it.

 

If I could get my Sony a55 flash to fire inside the housing (it won't - it raises, but not enough) I was just going to drill a couple holes in a small chunk of black UHMW plastic (one for a bolt, one for each fiberoptic cable) and go with that as my sync coupling. But I'm also kind of partial to keeping TTL as an option, so I would want a tiny microflash that gives the right TTL-ready signal and can mimic the camera's preflash-flash-quench so that say Inon strobes could mimic it. If it's just a matter of getting triggering...I may as well just use the Ike circuitry and connector since it's there.

 

And outside of Ikelite, coming up with a 'bulkhead' with a small clear window is still far less worriesome than a true electrical penetration, since once you get it sealed right it's sealed, and fiberoptics don't care if they're "wet" in operation unlike an electrical cable on the outside.

[davichin 18]

You just need a hollow nikonos connector (if you have the old broken pins one just take out the electronics) and this piece good for two optical cords (only one is fitted in the pic):

 

 

 

 

 

[cor 0]

Cool!

[Jesper64 1]

You just need a hollow nikonos connector (if you have the old broken pins one just take out the electronics) and this piece good for two optical cords (only one is fitted in the pic):

 

Looks interesting. So that Hugyfot adapter will mount in the place of any Nikonos Sync cable on a bulkhead with a waterproof seal?

What's the length of the adapter from the second o-ring (where it hits the bulk head) to the end of it? ie how much would it protrude into the housing?

[davichin 18]

Looks interesting. So that Hugyfot adapter will mount in the place of any Nikonos Sync cable on a bulkhead with a waterproof seal?

What's the length of the adapter from the second o-ring (where it hits the bulk head) to the end of it? ie how much would it protrude into the housing?

 

I think it will fit/screw in any nikonos bulkhead (just like any nikonos cord will fit in any nikonos bulkhead) with a double waterproof seal (the nikonos typical seal plus one more o-ring on the top). As for the length, I will have to measure it but you can get an idea from the third picture, around 3mm or so (equal or less than the electronic cables)...

[Jesper64 1]

I think it will fit/screw in any nikonos bulkhead (just like any nikonos cord will fit in any nikonos bulkhead) with a double waterproof seal (the nikonos typical seal plus one more o-ring on the top). As for the length, I will have to measure it but you can get an idea from the third picture, around 3mm or so (equal or less than the electronic cables)...

 

Makes sense that it would be a standard Nikonos sync cord screw thread.

 

Looking at the Hugyfot housing the Nikonos bulkhead appears to be much taller than the one on my Sea & Sea housing. That's why I'm querying about the length from the top o-ring to the end of it. I suspect it may protrude out a bit more than in a Sea&Sea housing than on the Hugyfot.

 

Thanks

Edited September 8, 2011 by Jesper64

[bvanant 191]

You actually don't need much of a circuit. Get a CR2032 battery holder and a superbright Red LED from Radio Shack. I put two batteries in the holder to get 6 V to over drive the LED. The hardest part is getting a good hot shoe connection, I disassembled an old strobe that had stopped working and just used the connector part. Wire the batteries through the hot shoe to the LED and you are good to go. The other tricky part is optically coupling the LED on the inside of the housing to the fiber optic bulkhead. Placement needs to be just right at least on my Nauticam. With an S2000 or Z240 at low power you can fire the camera as fast as it will go.

 

Bill

[blueglass 3]

You actually don't need much of a circuit. Get a CR2032 battery holder and a superbright Red LED from Radio Shack. I put two batteries in the holder to get 6 V to over drive the LED. The hardest part is getting a good hot shoe connection, I disassembled an old strobe that had stopped working and just used the connector part. Wire the batteries through the hot shoe to the LED and you are good to go. The other tricky part is optically coupling the LED on the inside of the housing to the fiber optic bulkhead. Placement needs to be just right at least on my Nauticam. With an S2000 or Z240 at low power you can fire the camera as fast as it will go.

 

Bill

 

Trying directly connection of a LED (in series with the battery) with a D7000, the LED stayed on continuosly after the first shot, it didn't work for me.

I have came back from my trip and the little device has worked perfectly in thousands of photos. It works with my own custom made fiber optic cables and connectors and Inon strobes. It won't work with stock Nauticam cables or other brands than don't let so much light to go through. Most probably it won't work with Sea&Sea strobes which have less sentitive light sensors.

You should respect the cooling instructions of the strobe manufacturer after several shots, otherwise you may burn the strobes.

[rtrski 20]

Trying directly connection of a LED (in series with the battery) with a D7000, the LED stayed on continuosly after the first shot, it didn't work for me.

I have came back from my trip and the little device has worked perfectly in thousands of photos. It works with my own custom made fiber optic cables and connectors and Inon strobes. It won't work with stock Nauticam cables or other brands than don't let so much light to go through. Most probably it won't work with Sea&Sea strobes which have less sentitive light sensors.

You should respect the cooling instructions of the strobe manufacturer after several shots, otherwise you may burn the strobes.

 

Might need a current-limiting resistor. Bill's LED might have one integrated, and yours might not have. I'm starting to seriously consider this route myself. Maybe buy a hotshoe 'extension cable' to get the shoe hardware for the contact points.

[bvanant 191]

Might need a current-limiting resistor. Bill's LED might have one integrated, and yours might not have. I'm starting to seriously consider this route myself. Maybe buy a hotshoe 'extension cable' to get the shoe hardware for the contact points.

One thing that is still puzzling to me is that if I hook up throgh the hotshoe, then it works fine. If I hook up through the PC connector then the LED comes on and stays on even if the PC cable is plugged into the hotshoe connector. I was under the erroneous assumption that both the hot shoe and the PC connector did the same thing but clearly not. I used very large LEDs rated for a 2.3 V and drive them at 6 more or less. They will fire through the standard INON optical cables; I haven't tried to see if they are capable of triggering the S&S strobe

 

Bill