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Automatic exposure / aperture

Tobi F.

New Member

first, let me introduce myself. I'm from Germany, so my english may be quite bad. Today I got a 500C/M with a Carl Zeiss Planar 80mm lens.

Attached to that lense, there is an automatic device,
which measures the light and then set the aperture with a motor.
On the left hand side, there is a battery case. Unfortunately I forgot to take
the batterys with me. (But I will go again there). So I cannot check the
functionality right now.

Does anybody have some information about that device ? Any name ?
There is no hint on the device itselt. Besides, that it seems to be originally
from Hasselblad.

Best regards,
Tobi F.
Welcome Tobi at Hasselbladinfo forum.

The 80 mm lens you got is one from 3 or 4 different focal lengths that were supplied by Hasselblad with an auto aperture device.

The motor and electronics can be powered by an EL/M/X camera or by a seperate battery with a housing that fits the accessoire rail of a camera.

Please note these aperture controls were most of the time fitted to a lens at the factory and supplied as a unit.

Hasselblad also sold the aperture control as an option.
Fitting those controls is a specialist job.

I copied a picture of three 250 lenses one of them also has the aperture control.
The 250 Sonnar was the longest lens fitted with this control.


first, let me introduce myself. I'm from Germany, so my english may be quite bad.
Your English is perfect, compared to the majority of people where I live in the US.
Hello Polypal,

thank you very much for your help.
It is exactly the device on that 250 at the left hand side.
There is a battery compartment attacht to the left.

Is there a special name for that ?
Is it rare ?
Does it work, or may it be better to use an external Meter ?

I'm coming from the amateur DSLR area. (Nikon D2h)
So dohing photography on medium format with a Hasselblad would mean
some kind of "slowing down" for me.

So I don't know, if I "need" that auto exposure.
Maybe selling (if worthy) and replacing by an "normal" lens ?

Best Regards,
Lenses with "automatic diaphragm control unit" , that is the name Hasselblad used for this device in their catalogues, were introduced in 1974.
They were first sold in 1975 and were phased out when the CF series lenses became available in 1982.
Four lenses were available with this option: 80 mm, 100 mm, 150 mm and 250 mm.
Converting a lens without this option was not recommended because fitting needed a lot of expertise and shims.

In 1977 the price for a standard lens was 1700 DM.
A standard lens with ADCU was about twice that amount at 3300 DM.
(DM converted with exchange rate at that time)
The German name is: automatische Blendensteuerung

The operation is quite simple:
You set the ISO value of the film, connect the cable from the lens to a suitable power source and the ADCU selects an aperture all within the range available for given lighting conditions.
When setting up you need to check the aperture needed is within the range the lens offers.
Of course you can bring the chosen aperture within the range the lens offers by changing the pre set shutter speed.

This device was meant for cameras recording a production process or at entry gates that needed to be guarded and similar applications
Operation is too slow for using it with handheld cameras and changing lighting conditions.

The resale value is 200-400 euro over prices for lenses without this device.

MF will not only slow you down it will change the way you operate completely.

Take a look at this thread:
I like to recommend the first quoted post written by Simon in Australia.

thank you again for the additional information.
Also about the origin price, and the product range.

I think, I will try to resale them and take instead an "normal" 80mm
plus maybe some portrait lense (150mm ?).

Additionally I don't have to handle with batterys, and it is much more
convenient to adjust the focus. And it points out the analog feeling.

Thank you also for the article. In general I was thinking this kind of photography, when I said "slowing down". Also this would be a reason
to get rid of the ADCU-lens.

But first I will need to go through the place, where I got it.
There is a big mess, because the neighbour who owned it died.

Chances are you may find some more lenses.
A 500 CM is not a logical choice for a 80 mm C lens with ADCU fitted.

Keep in mind later CF lenses are friendlier to operate.
They come after the C series lenses and cost more if in the same condition as a C series lens.

C stands fro Compur the maker of the shutter fitted to these lenses.

CF stands for Prontor and focal plane.
Prontor shutters were made by the same Zeiss owned company that made Compur shutters.
Focal plane shutters can be found in Hasselblad F series cameras.

CF lenses will serve both series bodies from Hasselblad, the 500 series and the later F series.
Hm, why is a ADCU-lens not logical for a 500 CM ?
I have the serial number UH 125228, so this would mean built in 1972.
It is labled with 500C, but according to the table, it is a C/M.
Also the matte screen (?) is changable.

A12 magazin is UH, A70 is UP.

The lens is definitely a C, as there is the synchro compur label on it.

Yes, I assume, there is some more stuff.
I remember a FUJI medium format camera.
Some 6x6 Rollei Diapositives, which mean, there is also a projector (Rollei ?)

But this is only the minor part.
Majority is 16mm filming gear.
I saw minimum four studiolike cameras (arri ?).
Projector. Cutting Table. And so on....
Lenses with aperture control were often used with motordrive bodies.
Camera set ups that record during longer periods of time while the light may change are more likely to use these lenses.

That is why a CM body is less likely to be used.
I did not say can't be used.
There is even a small battery compartment designed to power the aperture control when using a 500 CM.

It sounds like there is a lot to sought out next door.......
Ah, I see.
You mean like placing the camera on a tripod, and let it automatically
do shots of a sunrise each 30 Minutes, for example.

I do not expect to find another Hasselblad there. But, lets see....
Now you get the picture.
Hasselblad also made a range of timers that enabled these kind of interval registrations.

Set ups with multiple cameras, anything was possible.
Film magazines with up to 500 images on perforated film.
Just a small selection of the enormous range of options that was available.

Keep it simple and get yourself a nice 80 or 100 mm Planar lens to start with.
On Nikon my favorite is the 85mm / 1.8
So a 150 or 120 or 100 would be interesting.

Of course the normal view of 80mm will be the starting point.
The right angle to go "back to the roots".
Lenses to start with

Standard lens for 6x6 is the 80 mm.
If you can stand the loss of half a stop the 100 mm is a great alternative.
The 100 offers more resolution and has practically no distortion.
At the moment a good 100 mm C lens can be found for as little as 400 euro.
The later CF version will cost 250-350 euro more.

If you like the 85 in 35 mm a 150 Sonnar will be your next move.
A nice silver 150 mm C lens will set you back 200-250 euro.
That is even less than you will need for a black 80 mm with T* coating.

In short:
Silver lenses were the first generation starting in 1956.

In the beginning of the seventies Carl Zeiss started to supply improved coating called T*.
That coating improved flair and colour quality.
Still many users are quite rightly happy with their silver lenses.
Use of a good shade does more against flair than T*.

Some lenses exist as silver T* models.
Most black C lenses are T* coated but not all of them!
Black T* lenses cost about 75-150 euro more than similar condition silver lenses.

In short do not refuse a good silver lens at a decent price.
If you are after more comfort with an ergonomically better design look for CF lenses.
They will cost more and are easier to use but give the same quality pictures as early lenses.
It is frustrating but Zeiss did not improve much if anything on already very good designs.

At the end of the eighties especially the wide angles were improved.
These lenses are more expensive.

Happy hunting!