Instax 100 with a manual twist.

A few months back I got round to hacking an Istax 100 to pieces and reassembling it with manual focus, shutter and aperture. Despite having posted almost nothing, I have got a lot of interest on Flickr, then Georg (Polapix) made his own version from my notes, and I thought I might as well write a wee bit about it.

a PhotoBooth snap of myself with the beast

I had originally wished to keep as much of the original Instax as possible, and just replace the shutter and exposure unit. I failed at this whilst trying to identify the flash trigger. I think the flash uses an IGBT chip, or is rather overly sophisticated for the camera. Also the flash control board seems to be combined with exposure and shutter control. Odd design, as usually even on digital compacts, from my experience, the flash board has been separate. Even in a Nikon SB600 the inverter board is separate from the control board. So, yea, trying to identify the trigger I ended up loosing all of the electronics within the Instax, blowing a couple of components.

But all was not lost. The barrel was not rigid enough to move the weight of the tiny Vaskar 105mm anyway, so it is best to have it glued in rigid.

I believe the Instax 100 is a simpler chassis design than the later models, from what I gather. So, the microswitch which I have
drawn in my diagram is at the bottom and back of the camera, on the lowest gear in the drive mechanism. it fits into a cam to break contact. what I have written as “shutter switch” I then re-wired through the bus to the PWR button, the red one, on the back of the door, as the eject, as I thought there was less of a chance of me hitting it by accident. Again, I identified the bus contacts by ohmmeter, and just use the lower circuit board to for the bus contacts. So the red button initiates contact, and the cam closes the circuit, continues its cycle, then breaks the circuit once the film is ejected. I would recommend that you don’t solder onto the bus contacts, as I did, as things are too small, and a bump later shorted this out and ejected half a pack of film. So look for larger solder points on the board, if you plan to use this switch. obviously using the existing shutter button would be easiest, as it is large and already has wires coming off of it. After I blew the main circuit board i just cut all of the wires connecting the boards to the battery, to avoid any issues. The diagram and notes are in this scan of my Moleskine. The camera is a bit of a hassle to use, as it is a clunky machine with a rather small viewfinder, however it can be used with studio lights, and does produce images. Below is one example.

And here are a few more images of the camera in parts:

Tobias Feltus:

Graflex RB Super D: converting the back to take “standard” accessories.

Finally, after a couple of years lusting after one, I have a Super D (thanks to Bob Crowley and his find). It is in very good condition, in fact, almost new, and hardly used if at all. The only issues were need for a bit of lube in the shutter, and some minor cosmetic issues (like the leather coming loose on the lens door, due to retraction). However the Graflex standard back is not too useful today, or at least, it is not much use to me, as I want to use some Polaroid, and a Grafmatic sheet loader. The normal approach to this adaptation seems to be along the lines of what Bob did with his, involving taking a Grafloc back, cutting it down, and gluing it into the RB’s back. But I saw little point in this as Grafloc backs are expensive, to me, and also there is little need for a springback on a reflex camera.

The differences that I found in the Graflex back are:

the accessories are 6.5mm wider than the international standard

the accessories do not have a light trap lip sticking out, but rather a recess in them.

So, I had to shim the whole plane of the mount up by 1mm to create a groove to accept the light trap, and move in the tongue sliders. For most accessories they are fine the way that they come, however my Polaroid 545 back has two slots in either side, so I had to cut my sliders into the typical two-eared shape. I did this with a dremel and files.

But from the start, clean everything up, and the edge of the tray needs filing back by about 1mm so that it sits flush with the new raised level.

I then cut a piece of 1mm black styrene that I had to fit, and cut out the slot for the light trap. Then I glued this in with contact adhesive. The component has no structural value nor requirements. Then I drilled out and countersunk all of the necessary holes, including four new ones to move the lower screws that hold the slider supports in place. They had to be moved 3mm in, so I moved them diagonally to avoid weakening the frame. The slider bar supports are made of mahogany with brass inserts. To move them in the necessary 3mm I cut thin strips of 3mm plywood and glued these into the existing rebate with aliphatic resin, but any good PVA will do the trick. Then I primed and painted the brass tray with the new plastic shim, and the enhanced supports.

Re-glue the felt onto the base of the tray (cutting 4 new holes where the new screws go), and reassemble the base and rotating components. Screw the slider supports back in using the same screws, and reassemble the whole caboodle.

The last thing to do is to shim the ground glass and fresnel assembly. I just used two thin strips of the same 1mm styrene, as this was the only change in the focal distance made.

And now I have a Super D which can take all manner of film holders, including Fidelity double darkslides, as they are grooved on the side so they can be gripped by the sliders.

Tobias Feltus: