My DIY cable release

Intruduction
Figured out that cable release would be very useful for those tripod night shots (in addition to 2s timer for mirror lock-up). First I thought to get used RC-1000S from eBay, but given how much use it would see and how much it would cost, decision to make my own was born.

Google revealed that people have made these before, so I set my mind to doing it too.

Connector
Easiest way is to modify (use some sandpaper and razor) CD->SoundCard cable connector from older PC. Stepping of the pins on these is similar to socket on Minolta cameras. Digging around in drawers I found two of these. One had female connector with three holes, other had four. I first tried the 3-hole one, and after some sandpapering it fitted into the camera, but it was quite tight fit and it was possible to mount it in reverse cause I had to sandpaper positioning tab away to fit it. After closer inspection I figured out the problem - holes on this one were round and quite small. The holes on the 4-hole connector were rectangular, so I just cut one hole off and with very little sandpapering it fitted very well.

After the modification it looks like this (ugly, but oh well):

Lucky enough the positioning tabs (on the picture to the left) on the 4-hole one (after I cut one hole off) exactly matched positioning tab on the camera socket!

Wiring
Wiring for cable release is pretty simple - common wire and wire for focus/exposure and wire for shutter. You just shorten focus or shutter wire with common and thats it. Well not exactly - this is true for my film 7, but for 7D you need to shorten focus AND shutter wires with common for it to fire (film 7 fires even if you shorten just shutter and common and leave focus wire alone).

Simple wiring scheme:

This is as seen when looking at camera, note the positioning tab.

Shutter Button
First I thought that visit to local electronic supplies retailer will save the day, but figures that push-buttons like in cameras (with 3 positions) are really rare and rarely used elsewhere (technically what I needed was DPTT N.O. {Dual Pole Tripple Throw, Normally Open} push button). I called couple more retailers, but none of them had anything remotely like this in stock. Another idea I had was after reading how someone made cable release for Canon using two microswitches positioned slightly differently and connected to one button. I will try this in next version maybe!

Anyway, for starters I chose two separate buttons - one for focus, one for shutter.

Here they are:

Would have prefered different colours for focus/shutter, but they did not have them in stock...

Case
Getting small and ergonomic case to house the buttons was another problem, but digging around in drawers yielded the solution. Too bad it had one cover transparent though... on other hand - these days people consider seeing through innards of electronic devices to be "cool"! :D

Headphone jacks
I decided to not attach buttons to the connector directly. Instead I connected camera connector to female stereo connector (with very short cable), and buttons to male stereo jack with long cable. This way if I ever make that better shutter button setup with micro-switches, I wont need to spend time and sacrifice another CD sound cable. Also I could connect something else to camera (like couple relays hooked to parallel port of PC, or relays hooked to radio remote from toy car... that sort of stuff). Also it would be possible to extend the cable release by connecting cheap stereo extension cord in between.

Stuff used in the construction:


Several hours later...
Took a while to cut all the wires, make the holes in the box, solder all the wires, tape the cables... but it is finally ready and it works! Yippy!!!

Assembled release:


Connected to 7 with the Sigmonster:


Budget
buttons - 2x0.50$
stereo extension cable - 2$
CD-ROM audio cable - 1$ (but I used one I already had:)
Total - 5$ and alot of time...

P.S.
Next step for me is to make a better button which would work similar to the one on camera and in smaller and nicer looking case!

In no way this is anything similar to Minolta and upcoming Sony cable releases with their nice shutter buttons and solid connectors, but 40$ is still too much...

Edited by jEECHA - 28 July 2006 at 01:51

Not sure, made it in around 8 hour time frame, but I was watching alot of television and doing other things in between. Plus another hour yesterday buying the buttons and stereo cable.

The case I used feels pretty comfortable in hand actually - with trigger finger on the shutter button and middle finger on the focus button. I need to figure out where to get or how to make single button with three positions (Off-On{Focus}-On{Shutter}) before I think of new case though... Another idea would be adding a small switch for bulb which would shorten both focus and shutter indefinetely imitating someone keeping button pressed down for those really long exposures :)


Edited by jEECHA - 28 July 2006 at 02:31

Nice one, that plug is identical to the one i used for my modified verticalgrip, its ugly but sturdy. Works well.

Ill be doing later this year a few remotes with friends, so its good to know that the diagram with the pins are here on dyxym = less work to do, (even tough how many times you check they always end up wrong the first time)

Great post, i like DIY stuff!

Originally posted by jEECHA I need to figure out where to get or how to make single button with three positions (Off-On{Focus}-On{Shutter}) before I think of new case though... Another idea would be adding a small switch for bulb which would shorten both focus and shutter indefinetely imitating someone keeping button pressed down for those really long exposures :)

Have a look at this old DIY remote thread :-)

If you modify a mini RC toy car than you can even tinker a wireless rf remote control.


Edited by Micholand - 28 July 2006 at 14:32

After much thought I decided to advance this further.

1) Make a single button. My idea is to use microswitch with lever (those are very cheap and available) plus another microbutton (again - cheap and available) mounted between the lever and microswitch so that lever first shorts the microswitch, then when pressed further - shorts the microbutton as well. All this activated by the single button should mimic real camera shutter button.

2) Make a radio remote for this. Digging around on eBay, found exactly what I needed - VERY cheap transmitter (keychain type, much like car alarm remote) and receiver module (without relays, just plain radio receiver and decoder chip). There are plenty of assembled receivers with relays and additional ICs to achieve toggle switch functionality, but those relays are meant to drive >1A 250AC and thus are very big and also expensive. Ill just get some low current reed relays and connect them directly to outputs of receiver (or maybe add a transistor and couple resistors if the drive current will be too high).

If this works out the way I hope, it should not cost much more than 15$ for the whole thing too, and I will have a remote release for up to 50m and no cables!
I have some electronics background, but this is still pretty easy stuff, so anyone should be able to do this :) Will post results when I receive that radio kit and complete this (probably in couple weeks)!

Edited by jEECHA - 29 July 2006 at 03:24

My progress so far is:
1) found nice cheap ($0.30) case for the release/transmitter in local radio shop - small rectangular keyfob thing with 1 button;
2) also nice and cheap case for the receiver;
3) made a real shutter button (3-position, feels like one on camera) using two tactile switches (very small rectangular buttons which are soldered onto PCB). Basically I cut the prototyping PCB to fit into case, then soldered both buttons onto it, then made a bridge over them using small piece of plastic. Basically when pressure is applied on this bridge slightly off center, buttons that is closer gets most of it (simple lever physics). To make it even better I used buttons with different required pressure;
4) tested if the contacts for the camera can be driven by cheap transistor-output opto-isolators (relays are more expensive, and they require much more current, same for photo resistors coupled with led). Works like a charm, mere 3mA on the input of opto-isolator is enough to trigger the camera.
5) ordered RF remote control kit (decoder/encoder chips + AM transmitter/receiver). I had quite a trouble finding one which would do exactly what I needed (exactly reproduce state of two lines), but finally found one which should work. After a lot of thinking I realized that I probably could have got away with a bit cheaper kits from China (using 2272-M4 decoder chip), but that does not matter anymore;
6) decided on batteries to power this whole setup - 3V tablet for transmitter and 2xAAA 1.5V batteries for receiver.

Anyway, as soon as I receive the radio kit (it should be ANY day now), I will finish this - I have everything else tested, ready and waiting! When it's done and working, I will post pics and schematics, as promised.

I think you need a better connector than is possible with a soundcard socket - something that can be located into the camera by touch without fear of bending the contacts - then have a short cable with a connector on the end that can fit into a manual switch or an extention cable (so you can make the release as long as you like) - or a box capable of IR or radio triggering as required.

Using telephone cable/sockets works OK, but the neatest I've tried is a headphone extention cable and jack-plug.

Bob