Regarding the Horseman TTL meter - it slides in the camera like a film holder or Polaroid back. It reads through the lens so compensates for extended bellows etc. and you do not have to make any further corrections. It also compensates for any filters on the lens - works very well. We have one and used it until I had to retire due to health problems. Still have it if anyone is interested. Works with 4x5 format cameras but also works well using 120/220 backs on the 4x5 camera. John Gittens.
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