In response to a question on another forum I did a bit of research today.
It seems that many of us would like to use our Hasselblad backs without having to tether them or use the Hasselblad Imagebank. The Imagebank is a very useful addition to the HxD cameras and backs. One can quickly switch batteries as needed and it can hold over 1800 39MB captures. Marc Williams has used this device extensively.
However there may be times that one would like to power the back without the Imagebank. The following describes one way to appoach this without resorting to firing up the soldering iron.
Hasselblad uses Firewire 800 (ie 1394b) to supply power to the backs and also transfer the digital signal from the back to the Imagebank. The power output for the 1394b standard is approximately 12v. Apple specifies 12.8 volts for FW 800. I measured 12.77 from my 12 inch G4 Powerbook FW 400 port with my Fluke voltmeter. They also specify 13v ( ? 12.77v ) for their older IPOD FW400 power supply. So it is safe to assume that most FW output will be 12.8 - 13 v and this will be safe for the Hasselblad input as one can directly power the back from any older powerbook or mac. There is some question as to whether the newer powerbook pros can supply enough power...
Once I figured the voltage I felt reasonably comfortable to experiment with a few connections.
My proposed solution is as follows...however this is a bit of a kludge:
1) Belkin Firewire 400 hub - 6 ports very small and comes with a 12v 1.5 amp power adapter.
2) 6 pin to 6 pin FW 400 cable with Granite Digital 6 - 9 pin gender changer
or
Granite Digital 6 to 9 pin FW cable.
Plug the power supply to hub then 6 pin cable end to hub and 9 pin FW 800 end to Hasselblad back.
I have done this and comfirmed that the back powers up. When it is removed from my H3DII - 39 body the menu gives alternative camera choices including shutter cable and pinhole. You can actually initiate a capture without camera from the pinhole setting by setting the exposure time on the menu.
So AC is covered.
Now for DC - any 12v battery that has the correct connector for the Belkin...small tip + connector should work. I mentioned that the old IPOD FW power supply which is rated at 12.8v .67amp was able to power the Hasselblad back. I would assume that this is the lowest amperage one should expect to work but probably any battery with 1.5 amp ( as specified on the Belkin power adapter ) would be a more desirable choice. So substitute the battery at the Belkin hub for the power adapter.
Most larger battery packs come with multiple adapter tips so there should be one to work. I would caution you that many battery packs do not supply 12v but rather 15 - 22v and I would not want to fry the 20 - 30k back with the wrong battery. I have not investigated battery packs yet.
So you can power the back and capture to the CF card for very little money...an old Apple Powerbook allows Phocus to tether and confirm focus or the above gives you DC only. Total cost for the parts including battery is somewhat high in the $500 range depending on battery chosen.
I apologize for the rambling nature of this thread yet I hope that this helps.
Bob
It seems that many of us would like to use our Hasselblad backs without having to tether them or use the Hasselblad Imagebank. The Imagebank is a very useful addition to the HxD cameras and backs. One can quickly switch batteries as needed and it can hold over 1800 39MB captures. Marc Williams has used this device extensively.
However there may be times that one would like to power the back without the Imagebank. The following describes one way to appoach this without resorting to firing up the soldering iron.
Hasselblad uses Firewire 800 (ie 1394b) to supply power to the backs and also transfer the digital signal from the back to the Imagebank. The power output for the 1394b standard is approximately 12v. Apple specifies 12.8 volts for FW 800. I measured 12.77 from my 12 inch G4 Powerbook FW 400 port with my Fluke voltmeter. They also specify 13v ( ? 12.77v ) for their older IPOD FW400 power supply. So it is safe to assume that most FW output will be 12.8 - 13 v and this will be safe for the Hasselblad input as one can directly power the back from any older powerbook or mac. There is some question as to whether the newer powerbook pros can supply enough power...
Once I figured the voltage I felt reasonably comfortable to experiment with a few connections.
My proposed solution is as follows...however this is a bit of a kludge:
1) Belkin Firewire 400 hub - 6 ports very small and comes with a 12v 1.5 amp power adapter.
2) 6 pin to 6 pin FW 400 cable with Granite Digital 6 - 9 pin gender changer
or
Granite Digital 6 to 9 pin FW cable.
Plug the power supply to hub then 6 pin cable end to hub and 9 pin FW 800 end to Hasselblad back.
I have done this and comfirmed that the back powers up. When it is removed from my H3DII - 39 body the menu gives alternative camera choices including shutter cable and pinhole. You can actually initiate a capture without camera from the pinhole setting by setting the exposure time on the menu.
So AC is covered.
Now for DC - any 12v battery that has the correct connector for the Belkin...small tip + connector should work. I mentioned that the old IPOD FW power supply which is rated at 12.8v .67amp was able to power the Hasselblad back. I would assume that this is the lowest amperage one should expect to work but probably any battery with 1.5 amp ( as specified on the Belkin power adapter ) would be a more desirable choice. So substitute the battery at the Belkin hub for the power adapter.
Most larger battery packs come with multiple adapter tips so there should be one to work. I would caution you that many battery packs do not supply 12v but rather 15 - 22v and I would not want to fry the 20 - 30k back with the wrong battery. I have not investigated battery packs yet.
So you can power the back and capture to the CF card for very little money...an old Apple Powerbook allows Phocus to tether and confirm focus or the above gives you DC only. Total cost for the parts including battery is somewhat high in the $500 range depending on battery chosen.
I apologize for the rambling nature of this thread yet I hope that this helps.
Bob
