I also have to admit that the learning curve was paved by a number of cameras that were sacrificed to that learning curve… they now serve as parts cameras!!!! Most of the cameras that I work with are the Agfa Isolettes, though Zeiss cameras are catching up in volume. The most common problems with folders are:. As to shutters…no matter which model shutter, be it a Pronto or a Synchro-Compur, after 50 years, they need to be cleaned and sometimes adjusted.
Shooting lighter fluid or powered graphite into the shutter is a momentary solution… for a few days! The shutter must be partially disassembled and the parts flushed. So, for what it is worth, the roots of the Tessar are 3 years earlier than the Cooke.
I can't begin to say a Heliar is soft wide open, and the Tessar is harsh: they are the same. There is more variation from unit to unit than there is between designs. I have one of the last Heliars from Voigtlander, and to be honest, it is surgically sharp and contrasty, just like the Tessars of the same era.
It is amazing how much stuff one can accumulate in 40 years! The only important part of this monologue is that the mechanics of the camera determine how well a lens can perform. Folders usually rely on front cell focusing, unlike the Rollei, or a view camera. Other compromises necessary in folder design reduce the performance of these great objectives. But I'd go for the best mechanical camera rather than a lens whose legend you appreciate. But the Ercona seems to be the best bargain by a big margin.
I've just had a long hard look at the Vade Mecum entry on the Heliar, and my brane hertz. V is 5 lenses in 3 groups, but shaped quite differently from the Q19 design that I'd assumed was the "typical" Heliar. This is under the "c" paragraph in the group of Heliar lenses.
Then, under the "d" paragraph, there's some minutiae about the apertures and focal lengths, which suggests that those are what I have on the Bergheil and what we see on higher-end Bessae, and the statement that these Heliars "will be updated designs, quite likely with R.
Richter involved", but no word on what that updated design might be. So maybe the update is the difference between V and Q, or maybe I'm completely confused. Anyway, it's not clear to me how much these descend from the earlier Dynar-derived Heliars, nor what if anything the relationship to the Tessar is in practice. As I said, my brane hertz!
Jun 9, While the Vade Mecum is a fine effort by knowledgeable enthusiasts, Dr. Kingslake was in special category. He talked about some of the details you refer to, and gave the patent numbers for the designs.
Kingslake helped create the Institute of Optics at the University of Rochester, and became the head of lens design at Kodak in The story Kingslake tells about these designers and their work I think is that tremendous insight and brutal, hard, hard work went into the evolution of these lenses, and that as the Heliar evolution illustrates, it was not done in a vacuum. Harting , for instance, began at Zeiss, went to Voigtlander, and returned to Zeiss over a long career punctuated by two horrific wars.
In an era of manual computation and limited resources glass types, for instance lens design took years to prove or disprove ideas formed by the scientific method, and every one of the classic designs was limited by the era in which is was born.
Harting was decades removed from his design career when Kodak's Altman perfected the Heliar. At any rate, pick up the Kingslake to balance VM, and have fun. Last edited by a moderator: Jun 9, You must log in or sign up to reply here.
Show Ignored Content. When a new film is loaded, the paper leader is advanced to align the 'start' mark with an index mark at the top of the film chamber; the frame counter is set to a start position; the camera back is closed, and the film advanced with the lever until the counter reaches frame 1. The advance stops automatically i. There is a hole in the back of the top housing, which shows a red indicator when there is a film in the camera to warn the user not to open the back.
The shutter release is by the top right of the front folding bed; in front of the top housing rather than mounted in it. It has a double-exposure prevention interlock, which shows either a red locked or green unlocked indicator in a hole by the shutter release; there is a sliding control on the back of the top housing to override this.
The socket for a cable release is also on the back. It will also stand on the unfolded bed, with the help of two folding legs at the back. From Camera-wiki.
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