? about Changing a collapsible lens

[arbib]

I have noticed erratic RF focusing using my Collapsible lens on my Z1.

Do I mount it collapsed, focused at 1m or extended and why ??

Do I unscrew it Collapsed or extended and why ??

I think it is mounted extended and unscrewed extended. and at 1m. Is there a reason for doing it one way or another ??

One day it seamed to be off at 1m, then another day OK ??

I can always use the Hyper-focal scale for focus. But I was wondering if I was doing something wrong, or out of sequence. When I mount or dis-mount the lens.

The RF is aligned V and H too. Maybe the RF rocker may need adjustment ?? at least that is an easy fix if needed.

1st I want to make sure I am mounting/Dis-mounding the lens the right way. BTW it is a Collapsible I-50 50mm F3.5

 

[ZorkiKat]

You have to mount/unmount the lens extended, with focus setting at 1 metre.
The reason is to clear the way (or make sure that there is nothing in the way) of the RF sensor tip during mounting and unmounting. When the lens is at 1 metre, the mounting threads are clear and there is no protrusion which can damage the sensor tip. Same goes with extended collapsible lenses.

The sensor tip of the RF is pivoted, and its position determines how accurate the RF will be in measuring close distances. Unlike the roller sensors found in Leica or Canon, FED and Zorki have sloped tips whose shape and angle of slope are critical for RF accuracy. Careless lens fitting/removal can change the position of the sensor tip- a lens cam or protruding barrel can bang at it during the fitting or removal, and cause the sensor's position to change.

Have you tried adjusting your camera RF? You'd need to calibrate both infinity and minimum focus. Details are here:
http://jay.fedka.com/index_files/Page422.htm

If your camera has been previously serviced, there is a chance that the original calibrations have been changed. FED-1 and Zorki-1 are very delicate creatures that even the simplest repair can result in alteration to the original adjustments. The accuracy is sometimes determined by a small bit of paper- paper shims found under the lens mount. Make sure first that the lens flange to focal distance is exactly 28.8mm before doing the rest of the adjustments.

The I-50 is from a time when Zorki was supposed to be already using the 28.8mm working distance, a la Leica. It may be that your Zorki had some other lens before and its body was adjusted for that lens. I-50 were, according to
Soviet Camera literature, often bought as replacements. Thus, the body needed to be adjusted to conform with the lens.

Jay

 

[Xmas]

arbib

jay is 100%, but some lenses do not wedge lock sufficiently, i.e. before you shoot you need to extend the lens and turn it clockwise to lock or jam the wedges between the lens barrell and the lens mount, a view from the lens rear off the camera allows the wedge action to be seen. Some lenses wont wedge in place and may come undone (e.g. while setting the aperature), producing fuzzy photos.

Noel

 

[arbib]

Xmas
The INF lock is OK, It could have a little more tension. I don't have to push in to lock it or unlock it. but it does take a little nudge to do so. I have tightened the Adjustment screw about 3-4 mm turn get it were it is now. I may do another 1-2mm. but it is not a big deal. The lens sits tight on the flange too.

ZorkiKat
Thanks, very useful page, Now were do I get that rubber covering for the pliers ?? ACE Hardware ??

I am taking some pictures first at 1m (+/- a few Inches) at F/4-5.6. And some INF Pictures.....NOTE: If I use the INF Lock, the RF over shoots the mark. And the Focus triangle on the lens, overshoots the INF mark on the lens.

Well. I guess it's time to learn some home adjustment technique.

 

[ZorkiKat]

ZorkiKat
Thanks, very useful page, Now were do I get that rubber covering for the pliers ?? ACE Hardware ??

I am taking some pictures first at 1m (+/- a few Inches) at F/4-5.6. And some INF Pictures
Well. I guess it's time to learn some home adjustment technique.

Arbib

The rubber covering the plier's jaws in the pictures is "heat shrink insulation"- I can't recall exactly what it's called, but it's rubber electrical insulating material which shrinks to snugly fit over splices when heated. Inserting it on the plier's jaws and heating it will do the same. It should be available from hardwares.

Otherwise, tightly wrapping the jaws the with two or so layers of narrow rubber strips cut from old kitchen gloves should also work.

.....NOTE: If I use the INF Lock, the RF over shoots the mark. And the Focus triangle on the lens, overshoots the INF mark on the lens.

Quite normal with many collapsibles. The locked position doesn't always mean infinity position. In fact, you should calibrate the RF with the lens set to infinity focus and that position doesn't always coincide when the lens is locked to its tab. In some lenses, infinity focus is slightly ahead of its locking position. Don't be bothered too if the RF image "overshoots" at infinity if the lens is locked. Just ignore this and always refer to the lenses' true infinity mark when checking the RF.

You may wonder why the locking position and infinity focus doesn't always coincide with some lenses. Quality and Consistency issues. That's all that is to it- the lens will still focus good.

Jay

 

[Eugen Mezei]

I just bought a Zorki-1. (Going high on the fumes of the leather. 🙂
It has the collapsilble I-22.
When extracted it turns in place but I don't know if I'm supposed to hear some click? It also don't oppose resistance when I turn it back to collapse it. Is this normal? I can't press it back without turning, but I can turn it without the need to go past some resistance.

Also I found a plastic card between the back of the camera and the everrready case. I don't know if this is original or made by the previous owner? It seems a bit too thik to serve as a help for feeding the film.

 

[FrankS]

You should not be able to collapse the lens by just pushing it into the camera when it is extended and rotated to lock. Try extending it and applying greater rotational torque clockwise to lock it in place. To collapse it, you should need to unlock it by anti clockwise rotation (maybe 30 degrees) before the lens can be collapsed.

 

[Eugen Mezei]

Frank, I can't collapse it by just pushing it without rotating it anti clockwise. Also, when unmounted I can see the 3 "wings" doing their work as they should.
But I'm wondering if I shouldn't hear some click when I lock the extended lens in place.

 

[FrankS]

I think with FSU lenses the lock is like a wedge until tight.

With Leitz lenses there is a detent that is felt with your fingers. Not really a click.

 

[Eugen Mezei]

One side of the "wings" is wedge formed. I thought after this wedge portrudes into the opposite fitting, this clicks.
If this is the way it's supposed to be it means my lens works as it should. 🙂

Btw, serial number (of the camera) beginning with 44 doesn't mean this is the year of production, right? I think I remember Zorkis don't follow this rule.

 

[Dez]

One side of the "wings" is wedge formed. I thought after this wedge portrudes into the opposite fitting, this clicks.
If this is the way it's supposed to be it means my lens works as it should. 🙂

Btw, serial number (of the camera) beginning with 44 doesn't mean this is the year of production, right? I think I remember Zorkis don't follow this rule.

No click, it just wedges into place. This often does not work properly, and you may need to slightly (and carefully!) bend the tabs protruding from the back end of the collapsible barrel. This sometimes is needed even with a Leica Elmar lens, and the Industars were in no way at the same level of mechanical precision as the Elmar. Nowhere near the price either, of course.

Cheers,
Dez

 

[Eugen Mezei]

Lucky me, I don't need to bend them. It fits just fine. The camera itself also works very smoothly, but it does need RF calibration, it makes inf. at 7 m. I bought it at an "antiques fair", really it is more a flea market. So no wonder, it must have been knocking around in some box. But speeds being accurate I think it was in use until recently (recently = some years, maybe up to a decade). Same story with some of my FED-2, the ones used by the owners are fine, the others gummed up. I need a FED-1 or Zorki-1 with combined RF-WF. Badly! 🙁

 

[Penny Lane]

Btw, serial number (of the camera) beginning with 44 doesn't mean this is the year of production, right? I think I remember Zorkis don't follow this rule.

On FED & Zorki serial numbers: http://www.rangefinderforum.com/forums/showthread.php?t=43462

Derk