Tuesday, 19 November 2013

Perkeo I

This is a nice, medium format camera from Voigtlander. It is a direct competitor to Zeiss Ikon's Nettar 518/16 - that is, at the lower end of the enthusiasts' 120 cameras - and is a replacement for the Bessa 66. This is a folding camera which fits nicely in a (large-ish) pocket. It measures 125 mm wide x 85 mm high x 40 mm deep (closed) or x 95 mm deep (open). It weighs 483 g. In 1952, Wallace Heaton were advertising this camera at £22/11/6 for the model I have here (that is in old money and equates to £22.57 in new money. That is equivalent to about £1,400 in 2013 values).
Voigtlander Perkeo I

lens: Vaskar
focal length:  75 mm
apertures: f/4.5 to f/16
focus range: 3.5 feet to infinity
lens fitting: fixed
shutter: pronto
speeds: 1/25, 1/50, 1/100, 1/200
flash: F synch only
film size: 120

The lens is a Voigtlander Vaskar - 75 mm focal length and maximum aperture of f/4.5. The Vaskar is Voigtlander's cheaper lens (a more expensive Perkeo I came with a Color-Skopar lens) and has a triplet construction (again, comparable to Zeiss Ikon's Nettar on the 518/16). I have yet to see the result of using this camera, but it has a reputation for having soft focus in the corners. This is not a fatal flaw for me as I have no need for sharp focus in the corners although I am aware that others find this unacceptable.

The shutter is a Gauthier Pronto - four speeds being available of which only 1/100 and 1/200 are of any interest. This shutter has a delayed timer (Vorlaufwerk) which, unusually for a camera of this age, works well. Flash synch is provided for fast flashbulbs - I intend to try this camera with electronic flash to see if this works as well.

The shutter release is standard for the early 1950s - primary release on the shutter housing and a secondary release button on the camera's top plate, linked to the primary release by a lever.  There is also a cable release socket which is between the two - on the hinged door.  The secondary release has a double exposure prevention mechanism fitted requiring the film to be would on before the shutter can be released a second time. On my camera, this does not work very well at the moment. When I had a similar problem on my Franka Solida II, it sorted itself out after a few shots.

Blog copyright by John Margetts, 2014

Being a folding camera, there needs to be a mechanism to bring the shutter/lens forward, ending with the lens exactly parallel to the film. On my camera this is defective - a small strut has snapped half way along its length. When I received the camera, this folding mechanism barely worked and then very badly - the lens ended up at quite an angle to the film plane.  This needed attention with naphtha to flush out dust and dirt, lubricating with clock oil and repeated folding/unfolding to free up the many joints in the struts.

Perkeo I - folded
It now unfolds easily and seems to put the lens parallel to the film plane, judging entirely by eye. The test film will tell me how parallel things actually are. The broken strut does not seem to matter here. What does not work too well is closing the camera. to close properly, the lens must remain parallel to the camera body otherwise it will not fit into the available space. I suspect that the broken strut is there is achieve this. Without this strut, my thumb has to do its duty. 

As an aside, I have tried a new technique with this camera. When lubricating small parts, it is quite hard to apply a small enough amount of oil to exactly the right place. Getting that small amount of oil into the linkage is a matter of working the linkage and hoping. This time I have diluted the clock oil two parts of oil to one part of naphtha to produce a very runny oil. Because the oil is diluted, once the naphtha has evaporated I am left with 2/3 of the amount of oil I applied. Also, because the oil is now very runny I am hoping that the oil will run between the surfaces of the linkages more easily before the naphtha evaporates to leave a very small amount of oil in place. So far, the only downside I have seen is that the naphtha is very good at wetting surfaces and has carried a small amount of oil over all the surfaces around the linkages. I am not convinced that this is a bad thing.

Perkeo I - showing top plate
Before loading the test film, there are two things I need to do. The first is to use compressed air to blow dust out of the inside. Moving film through a camera generates a small amount of static electricity and this will pull any dust onto the film. After that, I need to check the bellows for light leaks. To do this, I wait until dark (about five PM at the moment) and shine a torch onto the bellows at close quarters. Viewing inside the camera, any light leaks will clearly show.  I have found one very large one. That broken strut I mentioned earlier has scored the bellows material and created a line on pin-pricks. These will need sorting before I try the camera. Otherwise, the camera is good to go.