For some time now, one of my cameras piling up is a Agfa Microflex 100, which seems to be still working flawlessly. At the very least, test shots with expired, self-developed Moviechrome film have yielded impeccable results.
The Microflex with its metal case is very well made and with its small dimensions an ideal pocket camera to follow you anywhere. I was really eager to use it with up-to-date colour reversal material with 100 ASA sensitivity and daylight sensitization, but the Agfa Microflex 100 is only designed for use with 40 ASA tungsten films – the standard film material at the time:
The film sensitivity is fixed at 40 ASA, a sensor is missing in the cassette compartment for sensitivity detection or even the possibility of manual setting of film sensitivity.
Exposure measurement of the Microflex 100 is not happening through the lens but by an external exposure meter placed above the lens. I took advantage of this circumstance in order to be able to correctly expose 100 ASA films: By using a neutral density filter with a factor of 2 (ND2) in front of the lens, the amount of light entering is reduced by 50%, which corresponds to the use of a film with 50 ASA instead of 100 ASA. This comes close enough to the camera-based sensitivity of 40 ASA to be able to expect correctly exposed shots.
However, the camera lens does not have a filter thread and due to the focus adjustment design, there is also no way to use a snap-on filter.
I helped myself with a 35.5 mm (1.4″) diameter filter, which gets mounted reversed (flipped) on the lens and is fixed with tape, in such a way that the sharpness setting is still possible without hindrance.
Now it was still necessary to outsmart the fixed “artificial light mode” of the camera and to pan out the daylight filter. The Microflex 100 also lacks a switch available for most other cameras. The filter can only be disabled in a cumbersome way if a contact is pressed at the bottom of the tripod thread with a sufficiently long screw. Appropriate screws are available in various versions in the online photo accessories stores.
Warning: The usual tripod filter screws are too short and do not disable the daylight filter reliably!
The first Fuji Provie meanwhile ran amazingly smoothly through this modded Agfa Microflex 100, without the film jamming not uncommon to this film stock. After the development of the film by Frank Bruinsma, it will become clear whether these measures have had the desired effect.