(To the degree that this may be useful or interesting to one or two others) … Anticipating more frequent use of my two-piece Rolleinars (close-up lens attachments) on my Rolleiflex 3.5F with 75 mm Planar, I wanted to get an idea of the focus distances they will accommodate in order to speed up selecting which one to use. I intend to make a knotted, heavy thread for my kit for more rapid measurement; so verifying the measurement datum on the camera was my first goal. My web research turned up a couple of notes on focus distances for Rolleinars, but they didn’t specify that the distances are from the film plane which, as I understand, is the usual datum. The film plane datum seems to me to be the aft edge of the vertical metal trim aft on the body (not the trim on film door). I used the left-side trim as viewed from the camera rear for my tests. First, to the eye, it looks darn close when the door is open and film rails can be seen. Second, I taped a measuring tape to a table, put a target with a vertical line at the dumb end of the tape, set the focus knob to 0.9 m, and slid the camera back and forth along the tape until focused (result was within 2 mm of 90 cm). Then I set 1 m and 1.1 m on the knob and got the same +2 mm results. I used a loupe on the focusing screen split image with the viewfinder hood off. So, I concluded that I found an acceptable (to me) film-plane reference on the body. Maybe Rolleiflex has published this info, but I don’t have it.
Then: check the focus distances from my film-plane reference on my Rolleiflex using my Rolleinars. I measured the following, rounded to the nearest centimeter because that’s the best I think I can tie knots. My results did not agree with any measurements that I found in the web searches I made. Perhaps either those data used a different datum, or that author’s equipment yielded different results (or both).
None: 86 cm to inf.
Rolleinar 1: 52-106 cm
Rolleinar 2: 40-57 cm
Rolleinar 3: 33-40 cm
I wouldn't ask anyone to test their Rolleinars right now for comparison, but if anyone already has done this, care to share your results?
Best,
Mike
Then: check the focus distances from my film-plane reference on my Rolleiflex using my Rolleinars. I measured the following, rounded to the nearest centimeter because that’s the best I think I can tie knots. My results did not agree with any measurements that I found in the web searches I made. Perhaps either those data used a different datum, or that author’s equipment yielded different results (or both).
None: 86 cm to inf.
Rolleinar 1: 52-106 cm
Rolleinar 2: 40-57 cm
Rolleinar 3: 33-40 cm
I wouldn't ask anyone to test their Rolleinars right now for comparison, but if anyone already has done this, care to share your results?
Best,
Mike
