I picked up a cheap vivitar 6000AF macro ring flash to do ocassional macro picks with my D1X, but when the flash is turned on, the camera won't take a picture. "r09" shows up in the frame count of the viewfinder when I push the shutter release. Does anyone know what the code means or what my problem is?
My SB-28DX and 50DX both work, and r09 shows up when I depress the shutter release but the shuter releases. The flash says dedicated nikon on box. The flash does fire when the test button is pressed, but it won't fire and the D1x won't release the shutter when the flash is turned on?
The D1x can buffer 9 shots in JPEG mode, so assuming it behaves in the same way as the D1 then "r09" isn't an error code - it's just the number of shots available in the buffer. In the same situation my D1 shows "r21" in JPEG mode or "r10" in RAW mode - the number of remaining shots available in the buffer.
The problems with the flash sound more like a problem with the unit itself. Does the "flash ready" indicator in the viewfinder come on OK?
The flash says dedicated Nikon, but that doesn't neccesarily mean that it is D1-series compatible. Your SB-28DX and SB-50DX both work because they're designed for digital SLRs. My hunch is that the D1X realises that the Vivitar 6000AF flash isn't D-TTL compatible and thus won't release the shutter.
I don't know how a D1-series camera works, but consider switching it over to Manual shooting mode where the TTL flash system is disabled. If this works, it may well be a compatibility problem.