Pentax 6x7 camera wont fire

[Josef]

A couple of months ago I purchased a Pentax 67 system that came with an old 6x7 body dedicated to a Polaroid NPC back mainly as a throw in. I got a bit excited and decided to start shooting Fuji Pack film for fun. Unfortunately the 6x7 body did not fire even when the battery check was lit with the red light.
I assumed the camera was broken and got rid of it for parts on Ebay but kept the NPC back.
A week ago I purchased another 6x7 body from KEH and have the same issues. I remember reading somewhere that the older bodies needed film in order to fire. Is that true? If true, how do you shoot with the Polaroid back?
Any help would be appreciate it!

Thanks!

 

[Nick Merritt]

These cameras won't fire without film in them, unless you "fool" them by opening the back, turning the exposure counter dial with your thumb to past frame 1 and holding that dial in place, then closing the back, and releasing the frame counter. You can then wind and fire the shutter to your heart's content. This is covered in the manual; see it at the butkus.org site.

I have to admit I have no idea how the frame counter/shutter charging would work with pack film. Something tells me you'd need to follow the "fooling" procedure described above.

 

[Poisson Du Jour]

It would sound to me the Polaroid back was experimental, rather than workable. As Nick Merrett pointed out, the 6x7 / 67 bodies require film to be loaded in the chamber and tension placed on the take-up spool in order to effect operation of the shutter. That's how the internal mechanics have been designed. The 6x7 / 67 bodies were never optioned with any type of film backs because of the complexity of the winding and tension design.

In normal circumstances, a 6x7 / 67 body that does not fire can have any one of a flat battery, jammed mirror, slipped winding pawl (that prevents the shutter being re-cocked) or some other malaise. The recessed button on the right side of the camera is used to reset the cocking mechanism (at the expense of a wasted frame). For the Polarioid film back to work, it would need to interface with the take-up spool of the camera. If it doesn't, the idea was simply a lightbulb moment with no workable way of firing the camera. I could be wrong, yes, but quite a few people have taken an axe and claw to these otherwise steadfastly remarkable cameras by removing backs and tweaking the internal business only to end up with a camera that will not do a single thing.

 

[Fixcinater]

Pentax manufactured a key to allow you to fire the camera without loading it with 120 film.

"SHUTTER COCKING KEY"

 

[dpurdy]

It would sound to me the Polaroid back was experimental, rather than workable. As Nick Merrett pointed out, the 6x7 / 67 bodies require film to be loaded in the chamber and tension placed on the take-up spool in order to effect operation of the shutter. That's how the internal mechanics have been designed. The 6x7 / 67 bodies were never optioned with any type of film backs because of the complexity of the winding and tension design.

In normal circumstances, a 6x7 / 67 body that does not fire can have any one of a flat battery, jammed mirror, slipped winding pawl (that prevents the shutter being re-cocked) or some other malaise. The recessed button on the right side of the camera is used to reset the cocking mechanism (at the expense of a wasted frame). For the Polarioid film back to work, it would need to interface with the take-up spool of the camera. If it doesn't, the idea was simply a lightbulb moment with no workable way of firing the camera. I could be wrong, yes, but quite a few people have taken an axe and claw to these otherwise steadfastly remarkable cameras by removing backs and tweaking the internal business only to end up with a camera that will not do a single thing.

Actually the Polaroid back for the Pentax 67 is well known and most pros using the system had one.
Dennis

 

[Nick Merritt]

Yeah, there's that shutter cocking key, which I've never seen. And maybe that's what's described in the manual rather than the stratagem I described above (which I think is a lot easier). But on further thinking, I'd like to believe that if you independently fooled the camera into thinking there's film in it by means of the trick I described, you should then be able to fire the shutter and as a separate step, pull out each Polaroid or Fuji film shot after tripping the shutter. But I've never examined one of these instant film backs to know how they're constructed -- does the back swing open like the stock back, for instance.

 

[Poisson Du Jour]

Actually the Polaroid back for the Pentax 67 is well known and most pros using the system had one.
Dennis

Yes, my framer once had a 6x7 with a humungous roll film back fitted (not a Polaroid), but it was factory fitted; it couldn't take a single 120 roll with that back. Explains why he had the camera all of 3 years then sold it (early-990s): he moved it about on a small studio trolley!

 

[Fixcinater]

Yeah, there's that shutter cocking key, which I've never seen. And maybe that's what's described in the manual rather than the stratagem I described above (which I think is a lot easier). But on further thinking, I'd like to believe that if you independently fooled the camera into thinking there's film in it by means of the trick I described, you should then be able to fire the shutter and as a separate step, pull out each Polaroid or Fuji film shot after tripping the shutter. But I've never examined one of these instant film backs to know how they're constructed -- does the back swing open like the stock back, for instance.

There's two kinds of backs, one that can work with a factory modified hinge which can replace the normal film back fairly quickly, and one that is made to be fitted permanently. Apparently the former type is quite rare compared to the latter.

And yes, you trip shutter and pull film separately, just like a Hassy Pola back.

 

[Josef]

Thanks for all the help. I'm pretty excited to be shooting Fuji pack film.

 

[Fixcinater]

So it works now? I'm definitely on the lookout for a Pola back for my spare 6x7 body as well. It has the infamous film transport issue so it would be well suited to Polaroid duty. Post results when you get them, please!

 

[Josef]

It works. You have to remove the Pentax back, punch out the pin that holds the latch together to the back, then install them on the NPC back. I'll post some shots this week.