Clive Woolls 
, Sep 09, 2010; 02:48 p.m.
Hi All,
Have had the new P67 out a few times now and delighted with the Velvia 50 results so far. Now I'm interested in using the camera for 2 hour star trails etc but appreciate the battery won't last long and will let go of the mirror ending the fun. I have recently seen a spare battery door that is wired for a remote battery box ... sadly this is still for the standard 4SR44. I wondered if it was possible to cannibalize one of these accessories to connect to a 6v heavy duty battery. I can't find amperage info yet but maybe I can simply measure the standard battery and fix up something.
Anybody tried this? I'm assuming it's no longer possible to get Pentax to modify the mirror mechanism to avoid using the battery power.
Alternatively the Pentax 645 is cheap as chips although the 67 <-> 645 adapter is more expensive than the body even if it was available! It would be so nice to have those 67 lenses doing double duty.
Btw, I wouldn't use Velvia 50 for the night shots ... green skies isn't my thing :)
Thanks
Jim Momary 
, Sep 09, 2010; 08:21 p.m.
http://en.wikipedia.org/wiki/AA_cell
Clive -
The SR44 / LR44 ~ 150 mAh.
Alkaline "AA" ~ 2,700 mAh.
Alkaline "D" ~ 12,000 mAh.
There's the ratio, order of magnitudes. That should indicate what you may need.
Jim
Frank Schifano , Sep 09, 2010; 10:28 p.m.
The amperage shouldn't matter much anyway. What you need for that camera is 3 volts. Using a battery with more capacity (amperage) simply means that it can deliver more current over a longer time period. Wire it up to two AA batteries and it should run forever. But that shouldn't be a problem anyway, since I don't think the battery is necessary to keep the mirror up. I used a Pentax 67 for a week a while back. Just for grins, I locked up the mirror and then removed the battery. The mirror stayed up until I reinserted the battery and cycled the camera.
Jim Momary , Sep 09, 2010; 11:20 p.m.
Doesn't the Pentax 67 take a 6 volt battery?
Clive Woolls , Sep 10, 2010; 08:07 a.m.
Yes it is 6V source. See extract from the User Manual.
Extract from Specifications page of the manual
Ray Butler , Sep 11, 2010; 12:33 p.m.
Jim Cormier , Sep 25, 2010; 07:34 a.m.
Clive Woolls , Oct 04, 2010; 09:18 p.m.
Hey thanks for all the great advice guys. Will get my schoolboy tool kit out and start hacking up some alloy :)
Clive
Audun Sjoeseth , Nov 10, 2010; 04:31 p.m.
