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Opening a tricky Focotar


Xícara de Café

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Hello!

I have a Focomat 1c enlarger which came originally with an excellent Schneider Componon-S lens. Recently I purchased a cheap but dirty Focotar 5cm f/4.5 and DOORX extension tube. I'm currently using the extension with the Schneider (this makes it easier to use but doesn't give true auto-focus). I sent the Focotar itself to a well-regarded lens specialist for cleaning. He said, because of corrosion, he was unable to open up the lens without risking damage and returned it without charge. In its current state the lens is of no use to me and I'm considering sending it to another technician. I'm wondering though if there are any special techniques that might be applied to opening up this particular lens. If anyone has any tips, please let me know, as I'll mention these to the technician.

All the best!

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4 hours ago, pico said:

Just my experience - the Focotars are over-rated. Your Comonon-S is probably better.

 

That's interesting. I suppose another approach would be to try and encounter a different extension tube that brings the Componon-S to the same length as the Focotar. Maybe hard to find though. Certainly the Componon-S is nice and bright to focus with, opening up to f/2.8 rather than 4.5.

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23 minutes ago, Xícara de Café said:

That's interesting. I suppose another approach would be to try and encounter a different extension tube that brings the Componon-S to the same length as the Focotar.

I forgot about autofocus. I disabled it on my Focomat in order to use different lenses.

Later today I will look for my old Focotars to refresh my memory. I had a couple of then - and laugh if you wish, I took one apart to clean it and never got it back together

Edited by pico
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i should really check too if the autofocus is actually working with the focotar, as it´s something I've not yet attempted (only with the Componon). Will try calibrating with the Focotar this evening. After a quick look this morning it seems the length from the base of the extension tube to the lens is approximately 4cm in the case of the Componon and perhaps 3.5cm with the the Focotar

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The Focotar 5cm (opposed to 50mm) is a very early lens and not as good as all three later versions. I think you would be better off getting any of the later ones:

- Focotar 50mm f4.5 (name is on the front ring around the front glass). Fine lens, but needs to be stopped down twice.

- Focotar 50mm f.4.5 (name on the side of the barrel). Fine lens made for Leitz by Schneider. Larger front glass, same 4.5 open aperture. Supposedly has a good 'flatness of field'. Here something that explains: https://www.photo.net/discuss/threads/zm-lenses-what-is-flatness-of-field.255471/

- Focotar-2 50mm f4.5 (name on the side of the barrel). Fine lens with a  bit more contrast and it is more 'open'. And you can use it wide open (focus your grain focuser as close to the corner as you can)

 

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On 4/24/2019 at 9:09 AM, Xícara de Café said:

i should really check too if the autofocus is actually working with the focotar, as it´s something I've not yet attempted (only with the Componon).

It took me an age to get around to doing this. When I did and focused the properly secured negative for the 10x magnification step, a curious thing happened. The focusing mount is positioned such, that when setting the marker clamp, the clamp is located in the "removal slot" on the mount. As such it can't be secured on the mount. I was using, by the way, the Focotar 5cm 1:4,5 together with the DOORX extension. Here's a photo:

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I wonder why this is. Can anything be done?

Thanks

 

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Xicara, Locate a Focomat 1c manual and see how to properly set the autofocus. It really is not difficult at all. With the extension tube you should be able to set just about any 50mm enlarging lens to the enlarger as long as it can fit. Some lenses are just too fat! Don't let anyone fool you. Any clean 50mm Focotar is a great enlarging lens. I just made some 11x14 test prints with three different Focotars. One very old with haze, one clean second version of the 'old' one and the Schneider version. It is nearly impossible to see any difference. If anything I really do not care for the Schneider version. The tonal separation seems to differ. But, they are all great. I was a bit shocked that the very old one with considerable haze did so well.

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4 hours ago, barrybed said:

Xicara, Locate a Focomat 1c manual and see how to properly set the autofocus. It really is not difficult at all

Thanks Harry. Yes, I've been doing just that. I've calibrated the focus before with the Componon-S and DOORX extension. After calibration, all worked well when I alternated between 10X magnification and 2.5X magnification, the two magnifications used in the calibration method, however when the magnification is moved somewhere between, the focus went off. I assume this is because the Componon-S is a different length to the Focotar. The Componon-S is longer if I remember correctly. 

When calibrating the Componon-S, the position of the focusing mount is such that the grooved clamp (which is used to return to the correct position when the focus is manually adjusted or bumped) sits where it can be secured properly and not over the slotted region where it can't be secured.

I have been sitting and securing the main brace of the the enlarger arm at the upper pin position of the upright enlarger mast (the real name escapes me). This is because i use an easel and don't project onto the base-board. It occurred to me that my easel is probably much thinner than that of the Leitz original, so I tried calibrating again lowering the brace to the lower pin position. This had the effect of moving the focus position on the focusing mount to the right, but not far enough unfortunately for the registration clamp to be secured. Later, I will try positions above and below the two pins and see if it solves the problem. I'll report back!

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If the focus is off in the middle range you just need to do the process a second time. That is not unusual. Sometimes it takes as many as three times to get it set perfectly. Eventually it will be right. If you have a 'thin' easel use the lower pin setting. If using a one-inch think easel use the higher one. There should be no reason to use anything in between the two pin settings. You will need to reset the autofocus when switching from one easel to another easel.

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I got the auto-focus working correctly with Focotar but it was not easy. I needed to position the arm brace 21.5mm above the upper pin on the upright (i'm going into such detail for my own reference!):

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In this position I was able to secure the focus registration clamp, but only just:

This position makes it necessary to crop a little an image projected onto 3.5X5" paper. The image is just a bit too big. 

I tried to position the brace below the two pins (remembering the focus registration clamp issues was having at the two pin positions), however this resulted in the inability to get sharp focus. At the brace location i tried (which allowed for the focus registration clamp to be secured properly on the focusing mount), i found the range in the focal cam adjustment wasn't sufficiently great enough to reach full focus.

I tried again with the Componon/DOORX and the effect is the same, focus goes out in the mid-range magnifications. The Focomat manual itself advises that only certain lenses can be used to achieve auto-focus. I'm curious to know which non-Leitz lenses and extensions you've  had success with? Perhaps my enlarger is missing something, i don't know....

All the best!

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Do you have a Anti Newton glass under the condenser? If yes, there should also be a 3mm spacer ring on the round ridge inside the condenser house. The spacer corresponds with the size of the Newton ring and is needed in relation to the automatic focus. Consequently, If you're not using the AN glass, there should not be the 3mm spacer and instead you will likely find a thin 0.5mm spacer ring.

The upper position of the pin for when you use a Leitz easel is more critical.

The above is about working with the Focotars. I only use those with automatic focus. When I use another brand lens, I forget about the automatic focus.

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Something is wrong. What I am thinking is that there may be a doorx  extension tube already stuck up into your enlarger. Try putting the lens in without the doorx and see what happens. If you can tilt the enlarger back without a lens look inside there with a flashlight. The set slide on my Focomats is set way to the left of the notch on the focus ring. You should not have to raise the head unit so high to achieve focus.

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Thanks M.Hilo and barrybed.

 

1 hour ago, barrybed said:

Something is wrong. What I am thinking is that there may be a doorx  extension tube already stuck up into your enlarger.

Yes the DOORX is attached and in the Focomat 1c manual that I have, there seems to be a DOORX attached to the focotar in one of the photos. My Focotar came with a DOORX attached. I bought it more for the DOORX then for the lens, because I wished to use the extension with the Componon. When using the Componon, without the extension, i have to screw out the focal mount so far to acheive focus, it practically falls out. I suspect the same will happen with the Focotar sans DOORX, but I'll try later tomorrow.

1 hour ago, barrybed said:

The set slide on my Focomats is set way to the left of the notch on the focus ring. You should not have to raise the head unit so high to achieve focus.

Yes, and this is the problem.

1 hour ago, M.Hilo said:

Do you have a Anti Newton glass under the condenser?

I wasn't aware that I do. Here's a photo:

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Edited by Xícara de Café
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What I mean is that I think you are dealing with two doorx tubes. I think there may be one from a precious owner that separated from the lens and is stuck in the enlarger. So when you are putting your lens in with its own tubes you are asking it in effect a longer lens. You need to look inside, up into where the lens screws in to see if there is a tube already in there. This happens all the time. Sometimes they are difficult to get out. You can see there should be two notches inside the doorx tube so you can get a wide tool up there and unscrew it. Is a a big piece of plastic or wood to sit in the notches and unscrew. Metal might damage the tube.

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Thanks, unfortunately not:

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That is so strange. I have two Focomats right here in front of me, set to perfect autofocus,  and the 'notch' on the focus ring is way out of sight in back, far from the set stops.  Just one more question: How many inches is it on your enlarger from the baseboard to the very first lower set-pin hole? On mine it is exactly 12 inches. (I see that you do not have the anti-Newton glass)

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