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I need a lot of help here


New Member
I need some help here and I am desperate.

OK, So what I have is a Rodenstock Imagon 120mm f4.5 lens that's attached to a Prontor Professional 1 shutter, that's attached to a Hasselblad converter that appears to have a focusing ring. Plus I have a lens hood, a filter of some sort labelled 4x and three snap-on disks labeled H=4.5/H=5.8, H=5.8/H=7.7, & H=7.7/H=9.5.

I know this lens is suppose to give a 'sparkling' soft effect to portraits and images in general - very similar to the black scarf technique only this is German engineered, so I am sure it was $$ when it first came out.

How the HECK does this thing work with my Hassey?

The converter doesn't have the cocking mechanism in it, so it looks like I have to hold and cock the mirror up and then depress the shutter some how. What I can't do is focus because the shutter is always closed and I can't figure out how to open the shutter long enough to focus.

I probably need a very fancy cable release of some sort as well in order to time this thing properly.


Regards, Art.

If you have a focal plane body (2000/200 series), then you just need a locking cable release to keep the Prontor shutter open all the time. With a 500 series body you can in theory make due with one cable release on the Prontor, but it would be easier with two, the second for your body's release.

The procedure would be like this:
Open the Prontor shutter (B exposure) with cable release and lock.
Close Prontor shutter by unlocking the release, and set proper/desired exposure.
With a second release open the body's aux shutter by pressing the release, or alternatively, prefire the body (mirror prefire).
With the aux shutter open then release the Prontor shutter using the cable release.
Release the body's shutter or unlock the cable release on the body to close the body's aux shutter.

When using the filter, the 4x means you need to compensate for the exposure by quadrupling the exposure or opening the aperture by 2 stops. I do not know what the discs are that you describe. Could they be used to stop the lens down?

Thank you Taras. I have a 503. That procedure makes perfect sense.

I know what the disk do. Here are a couple links about them if you are interested:

I guess I would add the disks after focussing and see which one gives me the effect I like.

One more question - which f-stop do I use? If the disk has an f-stop of 7.7 and the shutter an f-stop of 5.6, I assume f5.6 prevails, right?

Regards, Art.
> Yes , dead right , and in so many HANDBOOKS this fact is so purely > described . Very often misleading . Also in HASSELBLAD USERS GUIDE Jurgen