Minolta Semi II

vidgamer

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I have a (new-to-me but) very old Minolta Semi II, which is described here:

http://camerapedia.wikia.com/wiki/Semi_Minolta_(I)_and_II

I found a couple of threads here about the Minolta Auto Semi which is similar.

Mine's in OK "user" condition, I suppose. Bellows is intact, things seem to operate. This one has the f3.5 lens! It seems to be functional, as far as I can tell, but the exterior is deteriating a bit, and the "handle" on the side is missing. Still, I'm impressed when something mechanical this old survives this long.

However, things are kind of stiff. Whatever lubrication it had seems pretty dry, but I can still make adjustments to the aperture. The focusing works smoothly, though. Shutter works, although the slower speeds are off. If I set it to "10" it's not 1/10th of a second, but more like 1/2? Fast speeds are fast, but I can't tell if things are off. How do I test this? Am I just going to have to burn through a few test photos to find out? (I'm wondering if whatever error it has is non-linear -- maybe higher speeds are OK.) Curious design to the shutter-a spring automatically pulls it back and cocks it for the next shot. About the only thing "automatic" on the camera. ;-)

This is my first folder and my first foray into 120 film. I don't know if I can even pick up or develop the film locally, as most of the camera shops have closed recently :bang:, but I can always mail it off, I suppose.

From reading about the camera, it seems like it's original except for the film spool left in the camera that says Kodak. :)

It's a 6x4.5 model. Am I supposed to hold it on its side to get a landscape framing?
 
Since I do own an Auto Semi, I was probably part of those other threads :D

Based on your description, it looks like your camera is bound to need a good CLA. It is typical of old folders that the slow speed scapement (usually the set 1 sec - 1/2 sec - 1/5 sec - 1/10 sec) has plenty of dirt and/or nastier things that are preventing it from work (you mention a somehow stiff aperture, there may be some solidified lube on the blades too). Good news is, that a nice clean and adjustment should make the shutter come back to life.

There are amateur shutter testers that are OK to give you an idea of the speeds on your shutter. If you are handy with electronics, you can buy the parts and make yours for about 15 EUR / 20 USD more or less. A Romanian guy sells them already assembled for those of us less skilled with the soldering iron.

And yeah, if you want landscape with a 6x4.5 folder, you need to hold it on its side.
 
I played with it some more, and the aperture adjusts ok, but "catches"at one point and needs to be adjusted carefully. The shutter is now staying open very long when over about 75. Speeds of 1/75 or faster seem like they could be right - they are pretty quick, and i can see an effect against a tv, although i couldn't see scan lines or whatever. It's like night and day, once it gets past that spot on the dial. There must be some mechanical issue. Maybe I could use it as-is, so long as I only use the faster shutter speed.

I guess a cla would help, and cost more than the camera!
 
Testing the shutter

Testing the shutter

I looked up some techniques on determining the shutter speed. There's a way to build a circuit, but I don't think I have time for that right now. Looks kind of tricky to do, but once working, should be fairly accurate depending on the photo diode/resistor used? I also found a web page saying to photograph a TV (or view the image on ground glass) but that was a bit too tricky for me to get working. So, I found another idea on using a camcorder. Unfortunately, my software seems only accurate to 1/30 sec. (even though I know there are 60 fields!:bang:).

My best guess, after stepping through the video frames, is that the faster speeds are about 1/3 of what they should be. So, 1/100 is about 1/30, 1/200 is faster than 1/30, and 1/75 is about 1/25 (just a tad less than 1/30). I could be a bit off, but I think I'll just go with these estimates, burn a roll, and see what happens. I'm sure there's a bit of leeway allowed. I'll be off a bit anyway on my exposures, I'd guess, but if I can keep from being 2 stops off from the start, I have a shot at actually getting something decent. Or at least, that's the hope. :) Assuming this works, that's kind of limiting, but I guess I'll just have to rely on changing the aperture to get the exposure, but that's rather limiting indoors, even though I've got ISO 400 film. Hmm.

The slower shutter speeds are just so wacky, I don't want to use them. Sometimes it's sticking open! But, I need to test the camera, so I think I'll just give it a try, even though it makes me a bit anxious having to guestimate the speeds.
 
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