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Plunger Function In 1600f/1000f Swa/sw Body


Well-Known Member
Hello to all users of 1600F/1000F and SWA/SW cameras .

Looking at the back of the above mentioned cameras , we can see a little plunger coming out during winding the film transport knob .
What is this plungers function (in the body and in the back) and what would happen to the mechanics , if I would use a film back without "that little" hole .

My intention is to use the CFV BACK with my SW from 1956 . The sync cable would be required .
The CFV BACK does not have that little hole , but could be removed for the time , the transport knob is turned . This of course is not a very good solution .

Regards Jürgen
Hello Jürgen,

I am sure Hasselblad will be glad to adapt the CFV back for pre '57 cameras.
I know they are able to drill a 4 mm hole in the back to suit those cameras.
Only thing is the price: 477.30 euro plus VAT. :mad:
Maybe you can find a blacksmith in your village with a good drill stand to modify the back. :)


I am aware , that HASSELBLAD has rather high prices for any rework .
But you still forgot to add twice the postage of 24,00€ .

So , I know , my purse would get much lighter , but I still do not know , what would happen to the camerabody
if this little plunger is stopped to come out .


It is typical of you not be concerned what will happen to your CFV back when
the little pin hits it but to be much more concerned about the camera. :z04_schlaumeier:

This does not have anything thing to do with money invested but with a true love for old cameras. :)
The FUC will have to organise a special honorary membership if this happens again.

I just received an answer from Hasselblad concerning this matter.
They regret very much that development engineers overlooked the matter of the little hole for the CFV.
These guys were not even born when the cameras involved were already out of production.
As soon as the new CFV III will be produced this problem will be taken care of.
In the mean time there is no alternative but to send the camera to Sweden.
A detailed drawing will be available as a PDF for those who wish to modify their own CFV back.

True enough , the CFV BACK has been my most expensive investigation into the V-SYSTEM and has caused me the most trouble I ever had with any HASSELBLAD gear .
So why should I take care of it ? ? ? The most important thing is , that my SW stays alife . :z04_2171:
Just for others' possible concerns about the small pin that pops out of the back of the 1600/1000F camera backs to meet the hole in the original filmbacks, its purpose is to advance the frame counter on these original backs.

A man in Melbourne who owns this country's largest and best regarded repair centre (official repairers for makes like Canon and Nikon) and did his apprenticeship on Hasselblad and Linhof gear some decade ago, confirmed the pin's purpose.

He also commented that he believes that if a later back is used the pin's mechanism can be damaged if it is prevented from extending fully by a later model film back that does not have the "female" position to receive the pin.

He is currently away but promised to confirm the damage risk when he talks to a past colleague who is something of a technical historian. Stay tuned.

He added that when he was doing his apprenticeship, they regularly received later model backs sold with the first 500 series cameras and drilled a hole in the film back to receive the pin - many pros who had bought the first 500 series cameras also had 1600/1000F cameras. They needed to be sure their newer backs on their 500 cameras had the hole drilled into them in case the newer backs were mistakenly fitted to a 1600F/1000F camera.
Hello Simon,

It is not only a matter of the hole that is necessary not to obstruct the pin coming out of the early bodies.
Early filmbacks do not seem to align propperly with the gear in the body that transports the film with 500C and later cameras.
That limits the backward compatibility of the filmbacks for later cameras.

To me the function of the pin is not very clear. I will try to find out if this pin is the activator of the frame counter in the back. A new discovery for me at least.

I'm not a colector but my first Hasselblad was a broken 1000F for the french army baught in Saigon with a rodenstock 80mm lens and a back that seams to be a kief one.

When I repaired and then used all together it worked fine. Later I got a second hand CF 60mm and a 500cm new and the film did not move after picture one.

I understoud that the little pine informes the back that's ok to allow to move for next picture.

So I modify the back (see somewhere the picture in this forum) in putting a strong paper behind the hole (so it tell always the back to move the film) and so the back now works perfect with my 1000F and my 500cm

Conclusion the Pluger fonction is needed for early (unmodified) back.
And perhaps a hole in new back is needed to use old 1000F body.

BTW it was not stupid on one way. The film move only if you take real picture.

Ex. with "new" back: If the camera and back are loaded and then you remove the back and shot (without loadind) and then you put the back and load, you lose one picture with the new back, with the old back the film did not move. Perhaps at the begining it was told that the camera not used for months should be keeped unloaded.
Another good point was that when you travel your camera is not loaded so no acidental shots are possible. And when you need to shot you load the camera (or not) but the film move only if you made a real shot.
Please note: I have edited my posting of 22.6.08 above - nothing vital but for the sake of completeness.

Thanks Paul. Yes I can see that the alignment of gears does differ. The man I speak of is definite about the pin's function and some 40 years later he vividly recalls the work he did on the backs and cameras when he was doing his Hasselblad apprenticeship. But he wanted to check on the prospect of damage to the pin's mechanism if a later back is fitted to the camera. Stay tuned for that update.

It seems logical to me that whatever mechanism activates the outward and return movement of the pin could be damaged if it cannot move outwards fully when a later back is fitted.

Blowupster, your recollection seems consistent with the information I was given.
Hello Simon,

I poked the little hole with what looks like a steel ball and watched the counter of the back while I did that. Nothing happened.
I used Jürgens newly acquired 1600F with immaculate film back to perform this test. Nothing, absolutely nothing.
Maybe I should hit the mechanism a little harder with a longer pin?

The lens looks okay especially if you like mushrooms.
I could make an exquisite omelet with what grows inside that lens.

There is not much more I can do now but wait for my repair crew to return and get back to business.

Interesting test Paul to see how that plunger / pin works. I will soon hear from my friend, so will mention your test.

That is sad about the mould in the lens. I hope the repairer removes all of it.

Good luck with the CLA!
I have to put everybodies mind at ease.
I was just pulling a leg with my comments about the Ektar lens.

It is just as beautifull as it was when it left Kodak close to sixty years ago.
With some tender loving care from a guy who made the transition from poorly made
Hasselblad copies to the real thing it will be as good as new.

I vividly remember the time I came to him with my first Hasselblad 1000F.
The camera I found in Rouen, France.
The former owner runs a small shop for special photography items.
He was very positive about this 1000F. I did not have any idea at the time how
to get this camera back into a good working condition.

The technician was reluctant to start work on a real Hasselblad.
I found him a copy of the factory repair manual organised some spare parts and
a couple of weeks later I picked up the first of a long series of early "F" cameras.

I still own this 1000F. It was followed by more 1000F cameras who all carry
names after the city where I found them.
Well I have 2 1000F (only one working indeed). The plunger of the first one move much more than the other one. If I avoid the plunger of the second one to go outside, it's not a proplem. Perhaps this 1000F and associate 1953 back were modified in 1986 in this way.

For the CFV-39 and 1000F there is another problem: it's impossible to fit on the body as there is a strong frame inside of the body that avoid the CFV back to close.
As I noticed that my 1954 F 250mm/5.6 is particulary excellent on fuji Velvia I wonder if one allready modify a 1000F to allow digital CFV ? (Cut the frame)
(My 80mm/2.8 trinar is a dog with flare and resolution)
For syncronization it will be particulary easy with Bulb flash contact that fire just before the shot and stay open during exposition.