Hi everyone
For a recent assignment to digitise about 500 glass plates I used a Hasselblad 500c/m with the Zeiss Macro S-Planar 120mm f5.6 and the Leaf Aptus-II 6 back. The results were immaculate as long as I shot with strobes and used shutter speeds above 1/30. From 1/15 down to 1 sec the images had a purple cast and streaks throughout. The 50mm f4 performed fine down to 1 sec.
Leaf explained this with a bad shutter/flash pc sync. It seems that the back gets the signal that the exposure is complete (via the pc sync cable to the back) although the shutter is still open. If the back starts processing with an open shutter, the image file is corrupted.
However, the shutter speeds work fine down to 1 sec when using film and testing manually. A Hasselblad technician told me that the pc sync should either work when tested with a strobe or fail to trigger the flash. A bad sync only below 1/30 did not make sense to him, because the flash sync contact in the Compur shutter is mechanically maintained until the shutter blades close.
My question is what needs to be serviced in the lenses? Is this a matter of cleaning the sync port and making sure its inner and outer shell make perfect contact with the cable or has it something to do with the leaf shutter/flash sync?
I know I could just send my lenses to a Hasselblad repair centre for a CLA, but I am too curious to find out what really creates this failure.
Vinzenz
For a recent assignment to digitise about 500 glass plates I used a Hasselblad 500c/m with the Zeiss Macro S-Planar 120mm f5.6 and the Leaf Aptus-II 6 back. The results were immaculate as long as I shot with strobes and used shutter speeds above 1/30. From 1/15 down to 1 sec the images had a purple cast and streaks throughout. The 50mm f4 performed fine down to 1 sec.
Leaf explained this with a bad shutter/flash pc sync. It seems that the back gets the signal that the exposure is complete (via the pc sync cable to the back) although the shutter is still open. If the back starts processing with an open shutter, the image file is corrupted.
However, the shutter speeds work fine down to 1 sec when using film and testing manually. A Hasselblad technician told me that the pc sync should either work when tested with a strobe or fail to trigger the flash. A bad sync only below 1/30 did not make sense to him, because the flash sync contact in the Compur shutter is mechanically maintained until the shutter blades close.
My question is what needs to be serviced in the lenses? Is this a matter of cleaning the sync port and making sure its inner and outer shell make perfect contact with the cable or has it something to do with the leaf shutter/flash sync?
I know I could just send my lenses to a Hasselblad repair centre for a CLA, but I am too curious to find out what really creates this failure.
Vinzenz
