Graybeard
1-Jan-2016, 15:45
I recent bought a user Technika IV. It had no lens but came fitted with a 150mm rangefinder cam.
I am aware that Linhof advises that the camera and lens must be matched and the rangefinder cam custom ground for the specific pair.
Undaunted, I decided to see if I could calibrate the rangefinder for a 150mm Fujinon W that I had on hand. I was successful.
I brought the rangefinder and groundglass image into agreement at 9 feet, using a newspaper focus target and a 4x loupe to view the image. I brought the groundglass image into focus by sliding the front lens standard, very carefully, along the rails. It helps to use a feeler gauge between the front standard and a stop to judge motion.
Once this was done I checked agreement between the rangefinder and groundglass at 19 feet and 150 feet (It's winter here, the close targets were indoors and the distant one a greenhouse viewed trough a back window). The rangefinder and groundglass agreed exactly for the two more distant targets, to the extent of my ability to determine agreement, using the loupe. Done, I then set the stops.
I was also able this with a second, different, Fujinon 150W.
I conclude that I now have a lens/rangefinder combination in useable/useful calibration. They key point, to my mind, is that with the RF I can focus the lens as accurately at I can using a darkcloth and loupe on the groundglass.
Your mileage may vary, of course; hard to beat the price, though.
Good light all.
I am aware that Linhof advises that the camera and lens must be matched and the rangefinder cam custom ground for the specific pair.
Undaunted, I decided to see if I could calibrate the rangefinder for a 150mm Fujinon W that I had on hand. I was successful.
I brought the rangefinder and groundglass image into agreement at 9 feet, using a newspaper focus target and a 4x loupe to view the image. I brought the groundglass image into focus by sliding the front lens standard, very carefully, along the rails. It helps to use a feeler gauge between the front standard and a stop to judge motion.
Once this was done I checked agreement between the rangefinder and groundglass at 19 feet and 150 feet (It's winter here, the close targets were indoors and the distant one a greenhouse viewed trough a back window). The rangefinder and groundglass agreed exactly for the two more distant targets, to the extent of my ability to determine agreement, using the loupe. Done, I then set the stops.
I was also able this with a second, different, Fujinon 150W.
I conclude that I now have a lens/rangefinder combination in useable/useful calibration. They key point, to my mind, is that with the RF I can focus the lens as accurately at I can using a darkcloth and loupe on the groundglass.
Your mileage may vary, of course; hard to beat the price, though.
Good light all.