Extension tubes

[Bpyakd]

I can't seem to locate this info anywhere else. What are the exposure compensation values for 34mm and 68mm extension tubes on 50mm and 80mm PQ lenses? Thanks.

Ken

 

[tak]

Hi Ken,

I am new to this site.

I have had experience using the tubes and calculated and tested some of the data for the 80.

The 50mm PQ being retrofocusing is not recommended for use with extension tubes.

for the 80mm:

extension f/stop increment field (mm)
34 1 132
67 1 + 2/3 67

regards,

Tak