Δαφνη Ευτυχια Αρθουρος

I need an intervalometer. (It can be all electronic -- no solenoid -- because the *istD has an electrical shutter release connector.)

Is þe olde 555 chip and a cookbook circuit still the right way to go, or should I look up something else? (Or have off-the-shelf intervalometers gotten cheap enough that I won't save much by buying a chip, and SCR, and a few resistors and capacitors at Radio Shack?)

Right now I'm using the timer function on my cell phone and pressing the shutter button on the camera each time the annoying sound rings. (I don't need precise timing for what I'm doing now, so the variation in how long it takes me to walk over to the camera and then reset the cell phone isn't hurting anything.) It'd be nice to be able to just leave something running for forty minutes and go do something else ... and this isn't the first time I've found myself wanting an intervalometer.

Unlike a lot of other "I ought to be able to build it myself" electronic project ideas, I expect the hardest part of this one to be soldering a cable to the darned sub-mini (2.5 mm) TRS phone plug that goes into the camera. Maybe I can find a dead pair of stereo earbuds that failed someplace other than at the plug, and just splice that cable on instead of screwing up more bare sub-mini phone plugs than I've already ruined in my last project.