"Manual lens on D90 and built in flash will not fire r 18 error?"
I have a Kiron 105mm macro lens that works fine with my Sunpak ringlight with a Nikon module. When I try to use my flip up flash on my D90 or my Mount my Nissin Di622 I get an error code r 18 and the flash symbol just blinks in the upper left corner of the settings screen. I went to E2 and turned off TTL and still nothing. The camera does not function. I should be able to set the shutter speed to 30-250 and my f stop on my lens but the camera will not function never mind fire the flash. Do any of you use manual lenses with the camera's built in flash. Thanks JBD90