weird triplet design shutter lens i acquired from an old Ihagee 6x9 folder

[andrew_spence1]

Triplet lenses correct me if im wrong have 2 separate elements in the front and one in the rear and thats what google shows

I have  a Ihagee Triplex Anastigmat f1.45 10.5cm shutter lens and it has 2 elements in the rear and one in the front

the front single lens is in its proper engraved brass ring so they haven't been mixed up

is this an oddity of some sort it produces sharp images just like any other lens of this age that i have.

When i was cleaning the lenses i noticed that the rear lens in the rear couplet came out easily so i put in back in the wrong way round 

so after i put it in a lens board i had a look at the image on my busche pressman and to my great surprise it behaves just like a lens baby made for APSC digital cameras that i have

and the nicest effect is at f16

I think ill leave it like this and just use it as an effects lens as ive quite a few 10.5 cm shutter lenses 

its just that ive never come across one with 2 elements in the rear before

all comments welcome

regards Andrew

[David Lindquist]

3 hours ago, andrew_spence1 said:

Triplet lenses correct me if im wrong have 2 separate elements in the front and one in the rear and thats what google shows

I have  a Ihagee Triplex Anastigmat f1.45 10.5cm shutter lens and it has 2 elements in the rear and one in the front

the front single lens is in its proper engraved brass ring so they haven't been mixed up

is this an oddity of some sort it produces sharp images just like any other lens of this age that i have.

When i was cleaning the lenses i noticed that the rear lens in the rear couplet came out easily so i put in back in the wrong way round 

so after i put it in a lens board i had a look at the image on my busche pressman and to my great surprise it behaves just like a lens baby made for APSC digital cameras that i have

and the nicest effect is at f16

I think ill leave it like this and just use it as an effects lens as ive quite a few 10.5 cm shutter lenses 

its just that ive never come across one with 2 elements in the rear before

all comments welcome

regards Andrew

The diaphragm is also between the first and second element too, right?

This is similar to the 50 mm Leitz Elmar, a Tessar formula. Here the diaphragm is between the first and second element. In general with Tessar lenses the diaphragm (and shutter, if there is one) is between the second element and the rear two lens cemented group.

 

David

[andrew_spence1]

David thanks for the reply 

thats interesting about the Elmar i wonder why they did that

regards Andrew

[David Lindquist]

I have a hunch they did it that way because they wanted to make the lens collapsible. See an example here: https://www.kenrockwell.com/leica/50mm-f28.htm

This way the diaphragm mechanism which takes up a larger diameter space than the lens barrel itself is well forward in the lens assembly making possible a maximum length of slimmer lens barrel for telescoping (collapsing).

 

David

Edited February 26 by David Lindquist

[andrew_spence1]

david 

thanks for the reply