[GeneV]

A more elaborate and expensive, but flexible way to do this would be to buy two of the inexpensive wireless RF remotes on Ebay that work for Pentax. Connect the receiver of one to the camera and the other to a relay that will operate the lamp, making sure both are set to the same frequency. This way, you have no wires in between. Operation will be the same as Rico's suggestion. If this approach is interesting, I could go into detail about connecting the lamp to the relay to the remote receiver.

[ravenxbishop]

yes more details on which relay's to use and how they would be wired would be very helpful.

[BillM]

Hi Raven, Gene makes good point with portability also.

For all of us, remember, 120 volts A.C. at 5 milliamps can be lethal
have fun, dont forget to post some up.

[GeneV]

yes more details on which relay's to use and how they would be wired would be very helpful.

Though you can go much cheaper if you know what you are doing, I would suggest using this relay. ELK-924 Sensitive Relay. It comes with hookup instructions and it can be triggered with any voltage from 5v to 24v, so you can use a wide variety of batteries.

Follow the instructions that RioRico linked regarding finding which contact does what on the remote plug. Buy a fitting jack at radio shack. Solder wires to the contacts of the jack. As is detailed in the article, plug in one of the plugs from a remote. Actuate the remote, and use a meter or some other tester to determine which wires are shorted when the remote is pressed. Connect the wires that short to the screw contacts on the Elk Relay that actuate the relay. Follow Elk's instructions that tell you which are which. Attach the other contacts as though they were a switch in the hot (as opposed to neutral) side of the lamp cord.

Now, with one remote receiver plugged into the camera, and the other wired to the relay, the relay will close each time the shutter is tripped, and stay closed as long as the remote button is held.

I've built a lot of modules for my home's HA system. I would build the Elk module myself from parts that cost a fraction of the $10 they charge. However, I found these premade parts very useful when starting out. I'm not going there right now, but there are also modules from other companies that will trigger based upon WiFi.