deporange 11:54am, 20 February 2007
A photo amateur and strobist noob, I've learned a quite a bit here in the last couple weeks. I hope some Canon shooters might find the following helpful.

I had a Canon DSLR and 580EX before discovering the Strobist. After some research, it seemed the most effective way for me to get started on an off camera lighting rig was with the Canon Off-Camera Shoe Cord 2 and a second flash linked wirelessly with ETTL2. To overcome the 2 foot reach of the Cord, I found some great info in this forum and elsewhere about how to extend the Cord. Note - plenty of people have done this mod or a variation of it successfully; but it is probably possible with some effort you could end up with useless pile of insulated copper - take some care.

The detailed descriptions I found for this mod involved soldering (here's a good description) I wasn't interested in soldering so was happy to find aperture_lag's picture of his solder-less mod


1) Snip the Cord 2 down the middle
2) Strip 1.5" of the black casing on each side of the split Cord from where you snipped it - take care not to break through and damage the wires inside
3) You'll see 5 insulated colored wires surrounded by numerous thin bare copper threads. Gather and tightly twist the bare threads into a single wire
4) For each side of the severed Cord 2, connect the 6 wires to an RJ45 wall jack - I used this one, which came with a connector tool and instructions; but I'm sure many will do Obviously, you want to be consistent with the ports you connect each wire to, but the jacks are color-coded so it's easy.
5) Snip excess wire and wrap with electrical tape to cover any bare wire and add support to the connection.
6) Use a standard CAT5 cable to connect the pieces of the severed Cord, plugging the ends of the cable into the two RJ45 jacks. Depending on the application, you can choose the length of CAT5 cable that works best.

I completed this yesterday and it works as advertised. I can't speak to durability but I've read that this solderless approach has supported ETTL across tens of feet for months and hasn't broken. Apparently more of a problem is the connection to the camera/flash but that's an issue whether or not you extend.

Note - initially, I crimped each side of the split Cord to a male RJ45 connector, which I plugged into a female-to-female inline coupler (I included these parts in the picture above). Into the other side of the coupler was plugged the standard CAT5 extension cable. This approach seemed clean and modular, but I wasn't able to get signal continuity through the RJ45 connectors - not sure, but might have been my inexperience with properly inserting the wires into the connectors.
kubicekjim 9 years ago
I'm interested to see how far you can extend this. I've got boxes and boxes of cat-5 cable sitting around, I could go a couple of hundred feet if I wanted to.

btw, does anyone know if attaching two canon flashes to this set-up is as simple as just adding a splitter? I haven't been able to find any documentation for doing this.
William Alan Photo Posted 9 years ago. Edited by William Alan Photo (member) 9 years ago
Ha! I did exactly this a couple weeks ago! (except I found black female ends)
Lotto1 9 years ago
Do those RJ45 wall jacks come with male and femal ends? So they could be plugged in each other and back to be a short cord when used on flash bracket?

kubicekjim, the off shoe cord II has 2-way communication between the flash and the camera, adding another flash in the mix would confused the camera. However, you can split the sync and ground terminals and made a sync port out of it.
GomoX Posted 9 years ago. Edited by GomoX (member) 9 years ago
It's a better idea to put a male on one end and a female on the other end of the extension, so that you can use the cable without the extension too. Also, RJ45 will break with use. They don't withstand heavy usage, unlike good DIN-5 plugs. This said you can crimp a new one in a pinch and they are cheap so it's not big deal.
jayhan 9 years ago
i have mine extended to about 17ft. works fine.
asdrubal_diaz 8 years ago
just made mine and it works perfect....thanks for the tips..i have all of this stuff laying around so it was quick and easy...will try with a 50 footer soon....
toxonophile 8 years ago
I cut my OCSC II, soldered mini din connectors on the ends and can extend up to 24 feet with four, six foot keyboard extension cables. Works great. Not sure how many more cables I can insert into this loop.
Cheers! tox
Ndever 8 years ago
is the canon oc-e3 better for this or will the canon shoe cord 2 be best? I already own a '2' and wonder if i would gain new more with the oc-e3 cable (like ettl2, etc)? thoughts?
dosachodos 7 years ago
Boom! Thanks so much! I was looking everywhere for a solution and this $12 mod did the trick!! So long Canon ST-E2 (too expensive for what i need, plus take a wierd battery to worry about) or expensive Pocket Wizards. A perfect TTL solution!! Took me 10 minutes to use my existing off shoe cord.
johnoconnell 7 years ago
Wow this is gonna be handy - Cheers folks!
Since this has been woken up again, here's the one I made last week.
OC-E3 Cable mod.
mrstopadoodledoo PRO 6 years ago
Oh calamity!

Tried this today at lunchtime. However, I made the assumption that the copper was just shielding, and didn't join that up to anything.

Tried it out: flash didn't fire. :-( The camera (Canon 450D) knew there was something attached, but couldn't control the settings.
Then found the flash (a Sigma EF 530) wouldn't turn off. So I assume something was getting down the cable to the flash, but not in the way either the camera or the flash was expecting.

Nothing's broken - flash still works on the camera, but currently I have 10 feet of cat5 and two pieces of a OC-E3. Drat. Can anyone who's put one of these together successfully confirm that I should have connected up the copper, or have I done something else wrong?
Robertv! (Edinburgh, UK) Posted 6 years ago. Edited by Robertv! (Edinburgh, UK) (member) 6 years ago
Definitely connect the external screen. It is the screen to protect the data contained within, and the return signal for "ground" reference. Without that screen connected you will get all sorts of problems.

darylphotos PRO 6 years ago
You have to connect the copper or "shielding" as it's called. I had the same symptoms until I connected the shielding.
mrstopadoodledoo PRO 6 years ago
Thanks - all sorted now
1Kis 6 years ago
I'm sorry, I did everything but doesn't my Canon Off Camera Shoe Cord 2 working on wall jacks and Cat5e wires

I have 5 colored wires and the copper(shielding).

I've put the 6 wires (5 colored and the shielding) in the same position in both sides.

And doesn't work. Any ideas ?
aperture_lag PRO 6 years ago
Hey! Lookit that! :)

I'm glad my mod has come in handy for someone (apparently many someones, as I get lots of FlickrMail about my mod)

I use a tiny 1ft patch cable when I'm using the flash on a bracket or nearby (macro work, etc).

Otherwise, I've gotten it to work with my 50-foot roll of cat5e I have here. I usually use 25ft or less when I'm actually using this mod seriously. Haven't had a problem with it yet; I've had more problems with my flash shoes and connectors than the modded part of the cable!

Also, Juan Kis, match the colors on the sides of the ethernet jacks, not just the positions; in ethernet cables four of the wires change position mid-cable.

Happy Flickring!
danmorrisphoto 6 years ago
brilliant! thank you sir. works perfectly...
familiedelobelle PRO 6 years ago
This is awesome. I actually bought the opteka equivalent of the oc-e3 ($29 on amazon), and combined with this mod, I had a range of 25+ feet. I haven't tested a longer cable yet, but love this mod.

Thank you so much for posting this.
Electrolluc 5 years ago
hello to everyone ...
Lucas, from Ibiza, (spain)

I just wanted to show you my mod, because I got inspired at this post.
thanks to everybody for everything I've been able to learn here.

zzoldi 5 years ago
Just an advice: I used a hot glue gun to secure the wires. First i checked each wire for connectivity, than glued the individual wires to the RJ45 jack, than glued the coiled cord to the jack as well. This made the jack very secure at the ends of the coiled cables.
I just tested the setup with a 25' cat5e. works like a charm.
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