Minolta Uniomat

[Peltigera]

Bought this on Ebay - £7.00 including postage. After I bid I noticed the description said the camera did not work.  Oh well. Took the base plate off and added a spot of oil on the piece that had brown gunk where it looked like oil should be and it works fine.

It is the version 1 Uniomat with black surrounds to light cell and rangefinder window. There are no real controls - setting the match needles in the meter window sets an EV - I get no choice as to aperture or shutter speed. Upside - it has a 1/1000 top shutter speed which is fast for a leaf shutter. I shall try a short piece of film (courtesy of my new bulk film loader) this weekend and see how it performs.

[Berndt]

I shall try a short piece of film (courtesy of my new bulk film loader) this weekend and see how it performs.

Looking forward to the results ... and yes, 1/1000 sec is quite fast for a leaf shutter

[Stephen]

Minolta used a clever trick with the 1/1000th top speed, it only operates if required, sounds too simple, but it was an EV value coupled shutter, so only very bright light and high ASA ever required the camera to produce the top speed. With normal film and average light its top was probably 1/250 max. This exactly the way modern digital auto compact cameras behave. From memory I think it is a two blade shutter, with curve blades to compensate for even illumination.

Stephen.

[Peltigera]

Stephen, there are five blades clearly visible.

I am having problems with this camera. First, the tripod bush came partly loose and fouled the newly freed shutter release. Next, I managed to create a slight burr on top of the screw that holds the tripod bush in place - that also fouled the shutter release. Half way through my short test roll, the camera decided to remove film from between the perforations - not sure if that is the camera or the film - I bought the film (Kodak Plus X) as a part of a roll of bulk film that is some time out of date - might it be brittle? I might try it with a roll of APX 100 that is well in date - or on the other hand I might not. Not sure yet.

[Stephen]

It is the shutter that had two blades, the five petals may just be the iris blades, and there were several models with differently arranged shutters.

The two Minolta blade shutter was like the British AGI shutter, snap open fast, and compensate for uneven light with the blades shape, instant high speeds without a complex drive. As the drive to blades from the clockwork drive in the shutter, it was simple, the aperture mechanism could be coupled to the shutter so that for small apertures the blades of the shutter do no have to fully open, again aiding the high shutter speed.

The nuisance of the design was no manual uncoupled settings could be set, strictly a set of EV values. It may well be that they later added more blades to the basic design, which was very ingenious in being able to get to 1/1000th second speed on a compact.

The film might possibly be extra brittle, but carefully check the rewind knob shaft, clean it if dirty or dragging, and oil it lightly, it may be dragging on the film too much, also check the pressure plate is flat and true, again if out of true things can drag badly, risking ripping the sprocket holes.

Stephen.

[Peltigera]

The five blades look like a shutter not a diaphragm - still five blades if you look at the back of the lens as well. Searching on the Interweb it appears that there is no diaphragm as such, the shutter blades acting as the diaphragm as well as the shutter.

[Stephen]

You have one of the later versions, they altered the design to using the aperture blades, which unless carefully compensated for over exposes the middle or leaves vignetting of the corners. Many Japanese designs used this type to operate as fully automatic, it was easy to couple to a meter, and keep the design simple. The later Olympus Trip used the same ideas.
Stephen

[Stephen]

Have you had any film through the Minolta as yet?, they were reputed to have a very good lens, and the camera is very well built, with an accurate rangefinder.
The shutter was made by Citizen, the watch people, and the five blade one acts as it's own aperture on this model. It was marketed by Ansco in their own name in the States, one of several models they marketed i n the 1950's.

[Peltigera]

I have a part roll of film to develop - see my mention of sprocket hole damage above. I have put a touch of oil on the shaft carrying the sprockets but I don't think the trouble is mechanical as everything rotates very easily without any film in the camera.

I have another couple of roll of film to finish before I make up my next batch of developer (I don't have anywhere suitable to store the developer so I use it as soon as I make it up). Should be this week, hopefully.

[Stephen]

Just for reference, you may know this, if you want to store developer, put it in a plastic bottle in a freezer, it will keep indefinitely. Plastic is vital as it expands when frozen, Cola bottles work well.
Stephen

[Peltigera]

Not in Bestbeloved's freezer, I can't. I put a sealed plastic box of films in there once and that caused a right to do. Wouldn't dare put chemicals in there. On the other hand, she has agreed to stop dusting cameras (not the dusting I object to so much as the spray polish), so each to their own area.

[Peltigera]

In the end I used Agfa Vista plus film (£1.00 per roll in our local Poundshop). Here are some examples.  Shows the lens is susceptible to flare, but not badly so. All in all, I am quite pleased with the results but I don't think this will be a camera I will use much.

(Note: it is autumn here and we are not getting any sunshine. These were taken in miserable weather.)

[Stephen]

Doesn't look too bad in the shots, who is the street pianist?..a busker?
Stephen.

[Peltigera]

Yes, a busker. We get quite a few here in Lincoln and this chap appears occasionally.