Imagon 200-250-300 H values info

[Willie Jan]

Hi,

i did find a book from Alfons Scholz "Lichtbilder mit dem Imagon" which has a table with the calculated H values to F values.

lens 200 lens 250 lens 300
H 5.8 - H 7.7 F7.3 - F9.3 F7.7 - F9.6 -

H 7.7 - H 9.5 F8.9 - F11.3 F9.2 - F11.6 F9.1 - F11.5

H 9.6 - H 11.5 F10.7 - F13.6 F11.1 - F14.1 F11.0 - F14.0

He explains that the H values work when you go for the shadows, but if you have to work with the highlights (slides) the H values would be to low so the 2/3 stop of difference could be visible on the slide.

Maybe this is information for someone.

 

[Clueless]

Have to confess...I am Clueless as to how to use those numerical relationships.

 

[Willie Jan]

always fine when spaces are deleted...

lens 200
H5.8 - H7.7 = F7.3 - F9.3
H7.7 - H9.5 = F7.7 - F9.6
H9.6 - H11.5 = F10.7 - F13.6

lens 250
H5.8 - H7.7 = F7.7 - F9.6
H7.7 - H9.5 = F9.2 - F11.6
H9.6 - H11.5 = F13.6 F11.1

lens 300
H5.8 - H7.7 = -
H7.7 - H9.5 = F9.1 - F11.5
H9.6 - H11.5 = F11.0 - F14.0

 

[archphoto]

Looking for

Dear forum members,

For a project I am looking for see-thru scans of the H-plates of the 200 and 300mm Imagon lenses. In Dutch: doorzichtscans van de zeefdiafragma's.

I want to use these to drill holes in the aperture-plates of the latest Lensbaby so I get a Baby-Imagon for 35mm and DSLR.
Can anyone help me ?

archphoto@aol.nl