Sony EX1 lens remote socket wiring

I wanted to use a zoom remote, because the lens grip is not a convenient place to reach for when the camera is on a tripod, or other kinds of mounts (nor is it when hand-held).  Nor is the zoom rocker on the lens grip very good (it stops and starts when you try to do a slow zoom adjustment).  Actually I don't think much of the design of this camera at all.  Any amateur who's never used a pro camera may well be in awe of what it offers, but there's so many things about it that are major pain for anyone who's use much better real professional video cameras.

The lens remote socket allows connection of a zoom stub (giving you remote control of the zoom, and the record stop/start button, and record-review button, but no focus controls), though uses a plastic connector unlike any used on a professional zoom stub, it's the kind of connector often used for the viewfinder on industrial equipment (and an exact match for several old cameras that I have here).

But rather than try and make an adaptor, or buy a specific zoom stub for this camera (for which I could only find a horrible badly designed plastic thing), I wanted to plug in my old Fujinon SRD-91B Zoom stub directly, and still be able to use it with other pro cameras as usual.  That meant either sourcing the matching connector (which is available, though pricey), or scabbing one off an old lens, and fitting it to this lens.  I choose the latter (it fits with a bit of wiggle room), and it's a reversable procedure that only requires resoldering, if I wanted to.

The hard part was going to be discovering the wiring pinout.  It wasn't detailed in one service manual, and the information in another service manual was wrong.  So it was experimenting time with a meter and clip leads.

Not only was the socket diagram mirror-imaged (the diagram description said female external view, but is actually the socket lug view), but also also the wiring was rotated into a different arrangement of what each pin's stated purpose was for in that manual (what it said was on pin 7 was actually on pin 1, it's claim for pin 6 was actually on pin 2, working its way around backwards until pin 8 was the only correctly described pin).  Be wary of mirror-imaging, and you might find yours has the wiring colours going the other way around.

Starting with the easy things, first.  Finding which wire (when grounded) started and stopped recording, then which started the record-review playback (when grounded).  There's a risk of shorting out a power source when doing this, so it's best to ground the pins via a resistor for these tests.  Finding high and low voltages for the ends of the zoom pot, and finding medium voltages for the centre position of the zoom pot and the zoom wiper.  The final wire that the manual suggests is frame ground didn't seem to be connected to anything, so I left it isolated (either mine wasn't connected, had a broken connection, or was AC-coupled), and there's no way to connect that to my zoom stub unless the barrel of its 8-pin plug was connected to a cable shield.

When you disassemble the zoom grip on the EX1 you take off the half with the lens remote socket, the rest remains on the camera.  Press the TELE end of the zoom rocker down and wiggle the back end off first.  Be careful, the lens remote socket has a fairly short flylead to the circuit board inside, with a plug and socket on the circuit board.  Disconnect it, lift the outer half of the zoom grip away, and remove the lens socket from the grip.  Desolder the wiring from the lens remote socket, and stash the socket in your spare parts.  Wire up your socket (that suits your zoom stub) to these colour wires for these zoom stub functions:

NB:

In various different Canon and Fuji 8-pin zoom stubs, the (momentary contact) record switch is wired directly between pins F & E, the (momentary contact) return/review switch directly between pins G & H, all completely isolated from everything else.  And inside their lenses either end of the switches pins could be commoned.  I might hazard a guess that the zoom stubs have stand-alone switch wiring because, over the years, different lenses have commoned different sides of the switch wiring (I have one Fuji lens manual that shows E & G are grounded together in that lens).  The EX1 lens remote input simply grounds one pin each for RECORD or REVIEW via their switches, so the other end of those switch pins need joining together to a ground pin.  I actually joined E & H together, since that was easier to do, using F & G for the two switches.  But the above table, and adjacent digram, may be the more approved wiring method.

Not all zoom stubs use the reference voltage (on the yellow wire), which usually goes to a centre-tap on the zoom pot's resistance track.  Either they use some other trick to null out the centre part of the zoom pot (such as a dead section in the middle of the pot track), or you have to play with a centering pot so that the zoom motor stops running when you let go of the zoom rocker (on the stub and adjust it each time you use the zoom stub on a different lens, or on the lens and adjust it every time you use a different zoom stub on it, or on the lens and the stub).  You can connect that wire to the usual pin used for that function, or leave it disconnected if your zoom stub doesn't use it (bearing in mind that you may need to make a preset circuit up to adjust the centre-null of your zoom pot).

Also, the TELE/WIDE ends of the rocker don't always seem to be consistent across zoom stubs, and many of them have a reversal switch allowing you to swap directions to suit the lens or yourself.  I found my Fujinon zoom stub's zoom reversal switch mustn't have break-before-make contacts (shame on you Fuji for putting in a polarity reversal switch that shorts things together when switching over), and it would upset the camera if switched while the camera was on or the stub was plugged in, setting off an alarm that required switching the camera off and on again.

I notice that my zoom stub doesn't drive the motor as fast as the rocker on the lens grip.  Though that didn't bother me too much as I wanted the zoom stub for finer control of slow zoom speeds, and I'm not doing professional video work with it, such as sports recording, where fast zoom speed is very important (and you'd need a better viewfinder than the camera has to be able to see the ball).  It still goes fully-close quickly enough for setting up focus and pulling back to your desired shot.

The very basic, and completely analogue, functions available means that this lens should be useable with a variety of 8-pin and 12-pin Fuji or Canon zoom stubs, various clones, and even the cheap(ish) and nasty Libec ones.  Or you could even build your own.

There's no options for remote controlling the iris or electric focus controls, and the only possible way of having mechanical zoom, focus, and/or iris, would be to strap some custom rig around non-moving parts of the lens, there's no fittings already there for it.

I've been experimenting with using this camera to record some YouTube clips where I'm not behind the camera, and it's not always convenient to reach over to the buttons on the camera.  I don't have its infrared remote control, so a wired remote will nicely do the trick, and it allows you to play with the single-frame animation features of the camera without bumping the shot.

So I added a simple remote record stop/start socket to it, as well, just under the lens remote socket (it's in parallel with the 8-pin remote socket's record switch wiring).  Either can be used at any time, and neither needs unplugging to use the other, nor do they both need to be connected.

There's information about various zoom stubs wiring in the electronics section of my website, which can be used to work out how to wire the lens to a suitable socket for various different zoom stubs.