Zeiss Ikon Nettar

[Robin H.]

Hello all,

my Nettar 518/16 just arrived in the mail and I'm really excited about trying it out! (I haven't used it yet, but I'm already in love ) Both lens and bellows are in excellent condition, but as was expected the shutter is stuck when fired at 1/10th and slower. Since I'll be shooting handheld this isn't really an issue, but I was wondering if it should be fixed anyway.
If anyone has some tips, or advice in general about this camera, all is welcome!

 

[elekm]

The older folding cameras are very easy to service. Well, easy compared with servicing other cameras.

Briefly, what you should do at the minimum is get some optical cleaner and clean the lens. Use either plain white tissue or a clean 100% cotton cloth. Make sure that you remove any debris before cleaning the lens.

To service the shutter, you would remove the front and middle element, remove the face of the shutter, flush the shutter with a mix of lighter fluid and graphite, lube a few key parts and reassemble. Clean the shutter and aperture blades. You'll also want to clean the lens helical and regrease. And make sure that you recollimate the lens.

This sounds like a lot, but I can do this work in about two hours.

At the very least, clean the lenses.

 

[Nicholas Lindan]

Oh dear, I guess I am going to have to disagree with everything...

I have to recommend against graphite. I tried it on a recalcitrant diaphragm - not even a shutter - and I have since had to take the lens apart and remove the graphite dust from the inner lens surfaces before every use. And that is likely to continue until I take the whole thing apart and clean it in an ultrasonic cleaner full of tri-chlor, which I don't feel like doing any time soon and neither should anyone else.

You shouldn't need to re-collimate the lens if you put the elements back the way you found them. Put small witness scratches on the barrels and shutter plates so you can line things up again. In any case the standard Novar lens isn't very sensitive to alignment and such - it is a front-element focuser so it is always miss-aligned in a way.

If you have to undo and regrease the helical be sure to put a witness mark where the helical parted so you can line the helical back up properly when you re-assemble. Zeiss folders are much less prone to seized helicals than their Agfa/Ansco brethren, if it turns smoothly, leave it alone. If you are going to re-grease you will need to use a non-solvent grease. High vacuum silicone stop-cock grease is the best choice. Do not us a household grease or Lubriplate as it will simply evaporate and condense as foggy oil all over the inner lens surfaces. How do I know this - take a guess....

I wouldn't clean the inner lens surfaces unless you really have to - the early antireflection coatings are very soft. If it is a very early lens then the chances are that only the outside surfaces can be cleaned and the AR coating on the inside is so soft it can be wiped away. This is a problem with late-40's lenses, especially those from Kodak. If you clean use a good cleaner - Windex works best in my opinion - you want to have to do the least mechanical work - it is the rubbing that ruins the lens, not the cleaner.

My general advice is to do the least that is needed. The surest way to break a camera is to over-fix it.

 

[Steve Smith]

I wouldn't go that far yet. Just use it at the normal shutter speeds you would expect to use hand held. I expect they are fine if perhaps a little on the slow side.

With some use, you may find that the slow speeds start working again. If not, then you can decide if you want to have it repaired or try to repair it yourself.

For now though, just run some film through it to see how you like it.


Steve.

 

[ntenny]

I agree---try it out *before* messing with anything (apart from cleaning the outer lens surfaces, which is non-invasive). I have a number of old folders that either lack slow speeds entirely or stick too badly for them to be usable, and I can count the number of times that's been a problem on the fingers of one hand, I think.

The 518 is a real winner of a camera, simple and robust. There's one in the family that I borrow regularly, and it's just one of those cameras that somehow Has It---you know how there are some cameras that seem to add a little bit of magic pixie dust? Like that.

Thanks

-NT

 

[Steve Smith]

I have a number of old folders that either lack slow speeds entirely or stick too badly for them to be usable, and I can count the number of times that's been a problem on the fingers of one hand, I think.

The 518 is a real winner of a camera, simple and robust.

I have just had a look at mine to see what it is and it's a 518/16 too.

Mine is fine down to 1/25 then very sticky from 1/10 onwards. I assume 1/25 is where a secondary spring joins in to help close the shutter quicker.


Steve.

 

[Ole]

Mine is fine down to 1/25 then very sticky from 1/10 onwards. I assume 1/25 is where a secondary spring joins in to help close the shutter quicker.

No, 1/25 is the longest unbraked time. At 1/10 and slower the slow speed escapement kicks in to slow down the shutter blades.

And I have a 518/16 too...

 

[steven_e007]

I'm a great believer in not stripping down unless neccesary,too.

I have many medium format folders & my favourite are the Zeiss Ikon ones, such as the Nettar, because they almost always work well with nothing at all done to them (unlike Agfas, which always need the bellows repairing or replacing or Voigtlanders which usually need the leatherette gluing back on...:rolleyes

You may find the slow speeds will work after the shutter has been fired a few dozen times - if not, does it matter?

I certainly would clean the lens. Get the dust off with a soft brush first (so as not to scratch it), clean it wet with plenty of pure ethanol with a CLEAN lens cloth or lens tissue. If mucky inside, remove the front bezel (tiny screws) and then unscrew the front element. Ditto the rear element, ONLY if neccesary.

I have a slight difference of opinion about "Collimation". I won't claim to be an expert on such things, but I humbly submit that this word is sometimes misused in this context on APUG. If you strip a lens right down to it's components (take all the seperate glass lenses out of their mounts) then you will need to re-collimate the lens. This means alining each element so it's axis is perfectly centred on, and parrallel to, the optical axis of the lens. You will need an optical bench, a laser and special tools. Assuming you don't have them to hand... NEVER, EVER, EVER strip a lens down this far - a most folding cameras would never be worth enough to justify this being done professionally, either.

With a simple lens it is not neccesary. You can unscrew the brass front and rear mounts, clean them, screw them back in and all will be well (just be careful not to cross thread them!)

What you do need to do is reset the infinity focus - which I suspect is what some people mean when they say collimate...?

To do this you need a peice of ground glass to place in the film gate (you can improvise with tracing paper stuck to clear glass or with frosted plastic, or matt varnish on glass etc.) With the lens wide open, camera on tripod, dark room, focus on a bright lamp at a carefully measured 20 feet or so (not critical, but too near and the depth of focus at the film plane is too great - everything looks sharp). Get it as sharp as you can. Now rotate the outer bezel to 20ft without moving the lens and tighten up the screws. Check it at 10ft and then take it outside (with a cloth to go over your head) and focus on the moon or a very distant tree or something to check infinity. Once you got your ground glass organised this is a 5 minute job. I've checked all my folders like this and sometimes it is all you need to do to transform a 'lemon' with a suspected poor lens into a great, sharp shooting, precision instrument

 

[Steve Smith]

No, 1/25 is the longest unbraked time. At 1/10 and slower the slow speed escapement kicks in to slow down the shutter blades.

So it's a slowing down escapement rather than a speeding up spring. That makes sense.

That still confirms my view that it should be o.k from 1/25 and faster and not to worry about the slow speeds if it is only going to be hand held.

And I have a 518/16 too...

Of course. We wouldn't expect you not to have one!


Steve.

 

[Robin H.]

Since I have zero practical experience with disassembling camera's/lenses/shutters/etc... I'd probably screw up a lot of things that were fine, so I'll leave it alone.
It's not really necessary that the slower speeds are working, but it would be nice to have the possibility to make longer exposures (landscapes using very slow film, flowing water, moving clouds and whatnot).
For the moment, I'll just try and remember to adjust focus whenever I move around a subject

Thanks for the hints everyone!

 

[elekm]

OK, a few things here.

Because I believe that you wouldn't feel comfortable pulling the camera apart, I would clean the lens surfaces as best that you can. And if the slow speeds don't work, just look at the camera as having just fast speeds: 1/25 to 1/200 or 1/300 or whatever the top speed is.

Now, regarding the use of graphite. It's an excellent dry lubricant. What you do is mix a small amount with some lighter fluid. Mix it up and then use a cotton swab to apply it to the escapement. When the lighter fluid evaporates, the graphite is left to lubricate the escapement. Make sure you use some compressed air to blow out the excess.

Regarding collimation. If you remove the lens elements, you want to reset infinity focus. In fact, it's essential that you recollimate the lens. With a camera lens, there is a single point for infinity. A lens can focus before and beyond infinity. You want to ensure that the lens is set precisely to infinity. It's easily accomplished using an SLR with a telephoto lens. No need to remove the lens elements from their brass mounts.

 

[Darkroom317]

(unlike Agfas, which always need the bellows repairing or replacing or Voigtlanders which usually need the leatherette gluing back on...:rolleyes

Makes me feel better about the near mint 1947 Voigtlander Bessa, I just bought. The leatherette is intact but the shutter sticks at slow speeds, usually 25 and below. Now I just need to get more used to the scale focusing.

 

[John Koehrer]

If the Nettar is like most other folders, it has a continuous thread in the focusing mechanism.
All you need to do to get to the inner lens surfaces is remove the infinity stop and unscrew the front
group.
Interrupted thread helicals are used in lenses where part of the lens have to remain in position for connecting linkages that need to stay in alignment as the lens is focused.

 

[Nick Merritt]

If you don't need to take the lens apart, don't. Clean the front and back surfaces only. You'll be surprised how dirty a lens can be and still produce good pictures -- especially if you make sure to shield the lens from bright light sources (the sun is the most obvious one).

Don't bother with cleaning the shutter. Use the camera at the speeds you have, and it's possible the slower speeds will return with use. But even if they don't, you can use it as is in 95% of of photo situations.

I recently shot a roll with this camera and it produces really fine results. You should use it at f8 or smaller for best results (and as a scale focusing camera, you may want to have the extra margin for error that great depth of field gives you).