Parallel Cable for Controlling Long exposures on Canon EOS DSLR's

The following information describes how you can very easily and cheaply make a cable that allows you to control your camera and take a series of long exposures from within DSLR Focus V2.5

DSLR Focus has the following long exposure features built into it that will work with this cable:

  • Countdown Timer with voice option for manual exposures
  • Parallel port controlled Camera interface allowing Timer to automate long exposure   capture sessions. eg Take 15 x 2 minute exposures, wait 20 secs between each
  • Ability to control mirror lock times, time between exposures to let CCD sensor cool down plus more...

    See here for more details....

    The Circuit

    Thanks to Matthew Chang for developing this excellent diagram and allowing me to share it

    The Parts

    If you are havign trouble finding the 2N3904 transistors in Europe, you can also use the following:

  • 2N4401:,4450,2N4401,00.html

  • BC547/548 series,4533,,00.html?

    Just be carefull with the pinout which is opposite to the US 2N serie
    (C-B-E for the european BC serie instead of E-B-C for the US 2N

  • Construction Notes

    Depending on the size of the D-25 connector you get, you may have enough room to surface mount the 2 Resistors and the 2 Transistors. I did inside mine(see pics below).

    Pay careful attention to the pinout of the transistors. Study the inset diagram carefully before soldering to make sure you connect the right pins to the right places.

    Try not to let the Transistors heat up too much. So be quick in your solder to the pins on the transistors. Dint rush. Double check all connection sand make sure you solder the 2 base pins to Pin 2 and 3 on the D-25 Parallel adaptor.

    This circuit will work on all Canon EOS DSLR's ie 300D, 10D , D60, 1D. 300D users have got it easy because canon decided to use a standard stereo 2.5 mm jack. 10D and D60 users donít have it so easy. The plug canon use is proprietary and so you need to hack into one of the cheaper remotes to get the plug. You can either cut the plug off and then use stereo extension sockets to mate the plug to the cable in the circuit design above, or you can drill a hole into the side of the remote and attach a lead to this as per the pictures below.

    On a TC-80N3 remote:

    The Red Cable = Shutter

    The Yellow Cable = Auto Focus

    The Bare Copper Wire = Ground

    On an RS-80N3

    The Red Cable = Shutter

    The White Cable = Auto Focus

    The Bare Copper Wire = Ground

    Serial Cable for Controlling Long exposures on Canon EOS DSLR's

    If you are a beginner and this looks scary to you donít worry. Itís very easy. Just take it slow and surprise yourself.

    The Fine Print

    Build this at your own risk. If you build this exaclty as shown you will have no problems. If you stuff it up and it damages your Camera then I take no responsibility for you actions



    Some Samples Mine and of other peoples cables