Help: infinity focus with 9x12 Unknown beauty

[MikeMGB]

The camera may be a Ihagee, the front standard is identical to a Ihagee I have. Look inside the case, there may be a name plate attached close to the rear of the bellows.

[Pere Casals]

Although the image in the GG is not very clear because the crystal is quite dim, I think that I get focus at infinity at around 16 cm!!!! (from the rear of the lens to the film plane).

Antonio,

Check the focal (comparing with the Optar's magnification...).

You may have two abnormal things, one is a not working focus scale, the other is a great missmatch from nominal 135mm to effective (around) 160mm focal.

A possibility is that the lens was disassembled for cleaning but later the elements were not placed in the right position or orientation. I'd start by reversing elements, one by one and checking again, or purchasing another radionar (ebay S. Kreuznach Radionar L 2.8/45 on Pronto Shutter Working 12€) to compare elements' position.

Regards

[gimenosaiz]

Antonio,

Check the focal (comparing with the Optar's magnification...).

You may have two abnormal things, one is a not working focus scale, the other is a great missmatch from nominal 135mm to effective (around) 160mm focal.

A possibility is that the lens was disassembled for cleaning but later the elements were not placed in the right position or orientation. I'd start by reversing elements, one by one and checking again, or purchasing another radionar (ebay S. Kreuznach Radionar L 2.8/45 on Pronto Shutter Working 12€) to compare elements' position.

Regards

Hello, Pere!

Thank you again.
There is another scenario: a missing element... The image in the GG is more than acceptable when I get focus, I mean if you take into account the ground glass condition.
By the way, tha Radionar you mention is superwide !!! I'm going to test the camera with film ;-)

Regards!
Antonio

[Pere Casals]

By the way, tha Radionar you mention is superwide !!!

Well, perhaps it is from a 35mm camera...

There is another scenario: a missing element...

In theory it is 3 elements in 3 groups, so you should see 6 reflections if you place it under a lamp, if you only see 4 then there is a missing element

[Len Middleton]

Hello, Pere!
By the way, tha Radionar you mention is superwide !!! I'm going to test the camera with film ;-)
Antonio

Antonio,

The Schneider Radionar lens came in number of different focal lengths including medium format, but the Schneider Vintage lens reference only includes small format and large format, and does not include the Radionar in large format. If you have all the lens element present, I would trust the engraving on the lens with regards to focal length, rather than information from a web site that is not relevant to what you have.

And yes, missing a lens group may result in a longer focal length. In fact the focal length of a single lens group may be so long as to prevent you from achieving infinity focus with that camera.

Hope that helps,

Len

[gimenosaiz]

Well, perhaps it is from a 35mm camera...



In theory it is 3 elements in 3 groups, so you should see 6 reflections if you place it under a lamp, if you only see 4 then there is a missing element

Hello!

Ok, I'll check it!!

Anyway, the real PAIN is the ground glass ... I cannot assure than I'm really focusing .

Thank you!
Antonio

[gimenosaiz]

Antonio,

The Schneider Radionar lens came in number of different focal lengths including medium format, but the Schneider Vintage lens reference only includes small format and large format, and does not include the Radionar in large format. If you have all the lens element present, I would trust the engraving on the lens with regards to focal length, rather than information from a web site that is not relevant to what you have.

And yes, missing a lens group may result in a longer focal length. In fact the focal length of a single lens group may be so long as to prevent you from achieving infinity focus with that camera.

Hope that helps,

Len

Hello!
Thank you very much for the information!

Cheers
Antonio

[Pere Casals]

Anyway, the real PAIN is the ground glass ... I cannot assure than I'm really focusing .

you can grind the frosted side again, with silicon carbide powder, 600 grid. https://www.youtube.com/watch?v=hxC48_sd6BM

[Bob Salomon]

Hello!

Ok, I'll check it!!

Anyway, the real PAIN is the ground glass ... I cannot assure than I'm really focusing .

Thank you!
Antonio

A ground glass is not forever! You can always replace it with a modern one!

[gimenosaiz]

In theory it is 3 elements in 3 groups, so you should see 6 reflections if you place it under a lamp, if you only see 4 then there is a missing element

Hello!

I think that I can see 6 reflections ...

Cheers
Antonio