Mounting Rodenstock 120mm f/5.6 APO-Rodagon D Enlarging lens to 4x5 lens board

[Karlmera]

It is strictly a lens made for duplicating, you would find that at other then the ratios it is designed for that it would be a terrible performer.

But the two 75mm are also for duplicating and good taking lenses, why not the 120?

[Pere Casals]

But the two 75mm are also for duplicating and good taking lenses, why not the 120?

See page 3, file:///C:/Documents%20and%20Setting...en_web_sml.pdf

As it has been said, this lens will work very well from 1:2 to 2:1 macro.

In fact today it is sold mostly for Machine Vision cameras, in special for linear sensors.

Of course you may use a D as a taking lens for distant subjects, but then image circle will be the half, and performance will be lower than a lens that's not optimized for Duplication.

If you are happy with the 75mm then the 120 will do the same, but as Bob said, lenses for 1x-2x have a very different optimization than those for distant subjects. With a distant subject rays comming from an spot to the surface of the front element are nearly parallel, this is not the case for a very close spot.

Another thing is what you demand from the lens...

[Bob Salomon]

But the two 75mm are also for duplicating and good taking lenses, why not the 120?

No, they are not. The D series are specialized lenses for film duplicating. Not for table top or to infinity. They are also horrible enlarging lenses.

[Karlmera]

No, they are not. The D series are specialized lenses for film duplicating. Not for table top or to infinity. They are also horrible enlarging lenses.

And at around 1:1?

[Bob Salomon]

And at around 1:1?

The 120 is a very good performer at 1:1 with flat subjects like a negative or a transparency. There are far better lenses for 3D objects at 1:1 like jewelry.