Thierry Schreiner
2-Jan-2008, 14:47
Hi,
First of all, a Happy New Year to all of you LF guys out there.
My question is basically very simple, but as so often, I don't know the answer.
How do I calculate the flange focal length of a lens for a given distance?
Example: At infinity, the G-Claron 355mm f9 has a Flange Focal Distance (distance from back of the shutter to film plane) of 350mm.
Is there a formula to calculate the FFD for the lens if focusing distance is set at 10 metres, 5 metres, etc.
Thank you in advance for your answers.
Best regards from France
Thierry
First of all, a Happy New Year to all of you LF guys out there.
My question is basically very simple, but as so often, I don't know the answer.
How do I calculate the flange focal length of a lens for a given distance?
Example: At infinity, the G-Claron 355mm f9 has a Flange Focal Distance (distance from back of the shutter to film plane) of 350mm.
Is there a formula to calculate the FFD for the lens if focusing distance is set at 10 metres, 5 metres, etc.
Thank you in advance for your answers.
Best regards from France
Thierry