Hello,
I recently purchased a Rodenstock HR 100 to replace my Sironar Digital 105. The HR 100 was in a Sinar DB shutter, so I had SK Grimes put new F/stop scales on a Copal 0 shutter and mount the lens. I tested the resolution performance of the HR 100 at F4, F5.6, F8, F11, and F16 and was surprise by the loss of sharpness between F4 and F5.6. The reason I purchased the HR 100 was because of its reputed sharpness at F4.
The Service Manager at Rodenstock said HR lens can be adjusted on a MTF machine for a cost of approximately $450 USD, but he gave no indication whether the loss of sharpness that can be seen in the lens test between F5.6 and F4 is within normal accepted performance for the lens. My HR 40 and HR 70 do not show the same degree resolution loss between F8 and F5.6, though there is some loss of resolution.
Does the loss of sharpness between F5.6 and F4 on the attached file look normal to any of you working with Rodenstock HR F4 lens?
Has anyone sent HR lens to Rodenstock for adjustment, and did you see an improvement if the Len's performance?
Thanks, Drew Harty