I recently wanted to use a Brownie Hawkeye, with it’s accessory close up lens, to take portraits. I hoped I would get a nice soft-focus effect from the simple lens.

I therefore wanted to be able to use multiple studio flash, if I could. After some thought and experimentation, I was successful in converting the Hawkeye so it could use electronic flash. It was also important that the conversion be durable and dependable; and that the original features of the camera be preserved. I think I was very successful.

I decided to make this information part of the world’s database, for all those as crazy as me. It matters not why one would want to convert an old Brownie to electronic flash, only that one seeks to know. 

A flash triggering circuit is quite simple. It only requires a switch that closes a circuit at the moment the shutter is open. (Actually, the timing is different for a flash bulb than electronic flash. More on that later.) I therefore knew that it would only be necessary to hook the two wires from a conventional PC cord to the two connection points for the original Hawkeye flash gun. I started by getting an old PC cord that already had a bad female coupling on one end, and cutting the female coupling off. I then isolated the two wires, stripped some insulation off each, wrapped each around the posts of a Hawkeye flash gun with no batteries in it. And attached it to the camera. I then tested my theory by plugging the PC cord into a live electronic flash and pushing the shutter release on the Hawkeye.

It flashed. EEEHH HAAA.

I wanted a more stable and easier to use connection than wrapping wires, however. The two sockets for the flash gun provided the answer in the form of two potential screw terminals.

The top socket is already threaded for attaching the flashgun solidly. I determined that it was threaded for 10-24 size bolts. I only then needed to get such a bolt in the proper length, and one screw terminal was done.

The lower socket is simply a tube to accept the lower smooth pin on the flash gun. I checked it’s size, and determined that it could be threaded to accept a 6-32 size bolt. Now, here one needs a specialized tool. 

I have a rather complete set of taps and dies (tools to cut threads onto bolts or into nuts and sockets.) All you need for this job is a 6-32 tap ($2.25). A simple taper tap (for those more sophisticated machinists out there) will suffice. A tap wrench ($10.00) is very advisable; but not absolutely essential. If you’re like me and think that when you need a tool you should get it and have it for later jobs, I’d highly recommend getting an inexpensive kit of taps, dies, and their wrenches. I just found a set with most common US sizes on the internet for $16.95. This would be a “cheap” set. High quality sets can be $100.00 for a small set, or many hundreds for an extensive set.

Thus equipped, I threaded the lower socket and- - - Voila!!!,  we have screw terminals.  You would, of course, need to go to the hardware and get the two little “machine screws” if you don’t have them (10-24 X ¼ inch and 6-32 X 3/8 inch ).   Note that the old flash attachment can still be mounted; and without the screws in place, the outward appearance of the camera is unaltered. I placed crimp-on wire-end connectors ($0.15)on my PC wires for a finished look and a more convenient on and off.

Now the little matter of flash synchronization.

When electricity hits a flash bulb it triggers the ignition of flammable wire. The wire burns at near explosive speed, and creates a burst of very bright light. ( A 25B flashbulb has a guide number of 240 with ASA 100speed film which makes it brighter than all but the very largest professional electronic flashes. You can quite literally “light up the whole backyard”. ) Since this process is basically the ignition of a fast and bright fire, it is not instantaneous like an electronic flash. It takes a few millisecond before the fire really gets started and a few more to it’s peak. Therefore cameras that use flashbulbs actually close the circuit to initiate the flash before or just as the shutter is opening, timing things so the burn will peak when the shutter is completely open.

Electronic flashes, on the other hand, basically peak instantaneously. The camera synchs to close the circuit and initiate the flash precisely at the moment that the shutter is completely open.

This all means that the flash circuit on the Hawkeye will close, and an electronic flash would fire before the shutter is fully open. I confirmed this was the case by opening the camera, viewing from behind the lens, pointing a flash at the lens, and triggering the shutter. I could see that the flash was going off when the shutter was only about half way open.

I had to figure out a way to change that, if I was to be able to use my electronic flash.

I opened the inner workings of the camera, starting as described in my article about how to clean the lens of a Hawkeye, by removing the two bolts and taking off the film chamber box. Immediately behind that is the lens and a flat metal plate that can be simply lifted off to reveal the shutter mechanism and all of the flash trigger contacts, elegant in their simplicity.

I watched and analyzed, and analyzed and watched, and realized that the little brass arm that pivoted with the shutter pushed a small lever towards the front of the camera that was the actual contact that closed to flash the flash.

I knew that I needed to make that process occur just a little later in the shutter blades travel. I made an attempt to see if I could move the little lever further to the right so the pivot arm would not press it forward till the shutter was actually open. Lo and behold, it moved over as I shoved it with the blade of a jewelers screw driver. I had to use a fair amount of force with some degree of finesse to move it to the right but keep it’s forward-back position unchanged.

This appeared to do the trick when I flashed the flash at the lens while viewing from inside the camera.

Next I set up my portrait lighting. I needed enough flash power to yield an exposure of F16 with 100 speed film. (The Hawkeye has a fixed lens opening of about F16. ) So I set up four Sunpak 433 flashes bouncing two each out of two umbrellas. (For simple snapshots one large flash with a guide number of 120 could be used at a distance of 8 feet for perfect exposure on 100 speed film, with a tolerance range from about 6 to 12 feet on print film.

I got my wife to pose for a few shots. The photos came back exposed perfectly !!!!
 

Success ----- Success ---- Success  !!!!

I did discover that the Hawkeye with it’s close up lens really focuses at about 5 feet, not 4 as stated in the Hawkeye literature. Also, I didn’t get the soft effect I was looking for. The damned photos were entirely too good and sharp.

None the less I did accomplish this task for those of you that care.

Now I presume one would need to push that little lever back into original position if one wanted to use flashbulbs again.