Well I cobbled together a method of firing a flash through the Cokin IR filter. A second IR filter Hoya R72 was fitted to the camera lens.
The pics were taken in the workshop which was lit by flourecent tubes only - no daylight. A straight flash shot was taken with the the pop up flash to give a master to guage the IR effect.
As I am unlikely to take pics in pitch black, for the IR shot I selected an exposure that would benefit a bit from the workshop lighting. I really needed a more powerful flash than the SB-80DX as there is significant light loss. Exposure for the IR shot was ISO800, 2secs at f8, with the flash 30 inches from the subject.
Processing of the IR was Auto levels followed by the False Colour action I have previously mentioned, so nothing fancy.
Apart from foliage, which would reflect IR light, I added what I considered a IR dead object in the shape of the camera, again to see the effect. Glad I did now as there is a newly observed side effect to IR. Check out the self timer and lens release buttons on the front of the camera. IR light has seen straight through the plastic. A bit like an X ray.
I am well impressed with this first effort. I need to aquire some film now to try out a film filter which would make it an easier to handle flash set up. Even get back to multiple flash guns.
Managements calling, so I've got to go and help Stevie with her gardening now.
Don