Old Imagon, why teh yellow filter

[Cor]

I just obtained a pre-war 20 cm Imagon Tiefenbildner lens with a "gelb" ie yellow filter (and the 3 light sieves).

What is the function of that yellow filter ? To cut down the chromatic aberrations a bit ?

And why is Imagon spelled Jmagon on the lens ?

Best,

Cor

[Teodor Oprean]

The yellow filter is standard in black and white photography. What looks like "J" is just the stylized italic lettering for "I".

[Jac@stafford.net]

The yellow filter is standard in black and white photography. What looks like "J" is just the stylized italic lettering for "I".

After the yellow filter, they switched to a green filter, then an ND filter. Feel free to try other filters.

[Bob Salomon]

After the yellow filter, they switched to a green filter, then an ND filter. Feel free to try other filters.

Easier said then done. Imagon filters are in push-on, Imagon specific, mounts. Heliopan did make some up until a few years ago but the only way to get a different filter onto the lens is to find empty snap-on rings from broken filters or use tape. If you do find rings you can use you then have to get filter glass that is the right size to fit the Imagon snap-on ring.

Note: All Imagon accessories use the same push-on rings. The lens hood, the filters and the disks.

[uphereinmytree]

I found an appropriate size step up ring, filed the threads off and it works Fine as a push on filter holder. Fits as snug as the original parts. I don't use the strainers, but it wouldn't be hard to include them in the mix