http://www.nikonchat.com/nikon-releases/

Can you use a cable release on a Nikon D40? They want to take pictures of lightning and fireworks.?
He bought an SLR camera and I'm trying to build on my portfolio. Am very interested in fireworks and lightning. Please help with advice and information.
Check the MC-DC1 nikon ml-l3 remote. To be sure neither is compatible with the Nikon D40 can call: 1-800-645-6689 Nikon's Web site did not really say that the MC-DC1 is or is not compatible with the D40. He says the ML-L3 is but does not specify that you can use to Hod the shutter open for long periods. So give them a call.
Nikon D5000 Release Modes