Leitz Focomat IIc - setting the autofocus

J J Kapsberger

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How can I set the auto focus on my Focomat IIc? Do I simply use a grain focuser to focus the lenses as accurately as possible and then position the retainer in the groove on each lens? Or does this require special devices (i.e., professional attention)?
 
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Unless the lenses have been changed, the autofocus should stay the same. The way I used to do it was to focus with the head down sufficiently to give me a 5x7 on the easel, tighten the set screw on the lens and then shift it to 11x14 and see if the focus stayed put. Occasionally you have to reset either the 5x7 or the 1x 14 a couple of times to get it right. Once that is done, stick a negative in the holder and print first at the 5x7 setting and set the focus with a grain focusser. Do three prints, the 1st one dead on according to the grain focussing and the "tweak" the lens by very slightly turn it one way, do another print and the do a tweak the other way. Now check which print is the sharpest. Part of your shift has to do with the papers sesitivity (multigrade is more sensitive to blue light and there is a small shift in focus). Do the same test with the enlarger in the 11x14 position.You can use the same size paper, just check the centre and stick some 5x7 at the edges too. The latter will tell you if everything is aligned. This sounds a bit cumbersome, but once a IIc is set up, you really dont have worry about it again for many years.
I did get rid of my IIc several years ago as i kept buyng various 120 film cameras and playing with them (i did have the elusive Focotar-2 100/5.6 on it). By keeping the Ic only i am limited to 35mm and the temptation is removed (so far it has worked, but I still miss the IIc - it is a case of overengineered and overbuilt piece of darkroom equipment that has not been equalled. All right, the Durst 138 comes close, but wont fit in my darkroom),
I do have a IIc but it is a ultra high resolution ELCAN, based on a IIc chassi with a point source light and a 15" stack of hand ground aspherical condensors above and below the negative stage. Unforunately the 1974 vintage electronic shutter and light control has bit the dust and i have not bothered to replace it with the UniBlitz laser shutter control that would work. With the correct lens this enlarger will give you 250 lp on the easel - about 6 times what is possible with the best conventional enlarger design! It also barely covers a 35mm negative and has to be used wide-open ( with #3 filter it will give you 11x14 printing times of 0.9 to 1.1 seconds!). You actually focus on a specific layer of grain with this beast!
 
An af model IIc just went thru aussie feebay.... $100
They are too big to post, otherwise I may have brought it.

Tom, last night I spent 4 hours in the toilet/bathroom/darkroom with my Omega Enlarger. 2nd outing with it. I played with the lens aperature and timing on the same pic, about 12 prints at different settings trying to get a great print. I don't yet know how to D&B, but i can guess and it would take a lot of learning. Anyway, focus was the issue. I wear reading glasses and it was so hard. I gave up trying to get it perfect and ended up with "bracket focusing" I suppose.
So my question is: how arer we supposed to use these cheap grain focus thingies? When I got it i assumed it looked down at the print surface, but trying to use it, it seems to want to look up at the enlarger. I'll hunt up a pic on line of the stupid thing.
 
Carzee said:
I don't yet know how to D&B, but i can guess and it would take a lot of learning.
It's really not that difficult; you just stick your hands in the way of the light to dodge, and make a circle with your hands to burn. I usually start by adding/subtracting 50% of the exposure with any given d/b (e.g. 10 second burn on a 20 second exposure).

So my question is: how arer we supposed to use these cheap grain focus thingies? When I got it i assumed it looked down at the print surface, but trying to use it, it seems to want to look up at the enlarger. I'll hunt up a pic on line of the stupid thing.
They're supposed to bend light straight from the enlarger, this way there isn't interference with surface texture. Just set the focuser in the middle of the print and twiddle the focus knob until the grain (not the image itself) is most pronounced.

Hope this helps a little, but learning your way through a darkroom is really about technical experimentation, so have fun with it!
 
Thx. It is definitely fun so far. I did get acceptable prints at f11 6 secs and f8 3 secs -seems they are the same in effect.

Also, Print focus is easiest at f4 on my EL nikkor 50 f4. I just presume the grain focus is done wide open as well? Would it just be that much easier all 'round with the f2.8 version lens?
 
Sorry about the delay in answering! My feeling is that a bad grain focusser is actually worse than none! A good one is going to be a bit pricey, but it will save a lot of paper in the future. Mine is a 32 year old Omega, built like a tank. It has the advantage of having a long surface mirror that you put in the light path and an ocular that is adjustable and swivels and as the mirror is long enough, you can also check corners.
As for focussing wide open - if you are doing small prints (5x7) you can get away with wide open focussing, but once you start going up in size, always focus at working aperture as even with premium enlarging lenses you will have a minute shift of focus and that will show up on a 11x14 or larger.
Always put your fcousing aid on a piece of paper of the same thickness as your printing paper. This ensures that your focus is set for the paper surface, not the easel surface.
 
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