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  1. #1

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    $1 Lens... Now what?

    Ok, so I couldn't resist. I picked up a "Kodak Projection Anastigmat f:4.5 161 mm " lens.

    I figured, what the %@$# it's only a buck!

    So the Fstop ring is kind of loose, and the screw that holds it in place, seems to turn without much resistance. On top of that, there looks like there are spider webs inside it. As well the very rearmost element had a sort of darker (darker than clear) halo around it.

    So for a buck I have a fun little toy, to play with on my desk. However, as a learning experience, and since it is only a buck, what do I have? And what are the steps and techniques to learn/practice to fix them.

    I assume what I think looks like spider webs is fungus. I have heard this is killed by direct sunlight, how much and how long? Can this lens be taken apart or is it cemented together?

    I can look through this at something in fairly clear focus, then flip the lens around and it stays in focus, does that mean it is symmetric?

    Are there shutters big enough to hold this? I don't have my calipers here with me, but it seems pretty big..

  2. #2

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    It is an enlarging lens in barrel.

    It is a tessar type. If it is like the other EKCo lenses I have, the front and rear cells should screw out of the barrel. The front cell contains two elements with an airspace between them. The front cell's rear element should unscrew. The rear cell contains a cemented doublet that can't be taken apart.

    Killing fungus isn't enough. It also has to be removed and the glasses cleaned.

    At even odds, there's no shutter the lens' cells will go into. And since it is an enlarging lens it will be useful as a taking lens only closeup.

    In general, buying a lens in barrel in the hope of finding a shutter its cells will fit makes poor economic sense. A used lens in shutter usually costs less, often significantly less, than buying a lens in barrel and having adapters made that will allow the cells to be put in a shutter and buying the shutter. And the result of putting a crappy lens in barrel in shutter will be a crappy lens in shutter. Better just to get a decent lens in shutter.

    There are exceptions. Before offsetting income, which reduced the net cost to around $250, buying a 38/4.5 Biogon in an obscure and unusable shutter and having it put in a new Copal #0 cost me $700. Well worth it, even without the offsetting income. But the 38 Biogon is an exceptional lens and a Projection Ektar isn't.

    Until you learn more -- at the moment there's little evidence that you know what you're doing -- don't buy anything. A new acquisition is a distraction. Even for $1, your new paperweight is a distraction.

    Good luck, have fun,

    Dan

  3. #3

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    Thanks Dan. I assumed from the "Projection" that it was an enlarging lens but wasn't sure. Here is what I have determined. With firm pressure against my palm, I was able to unscrew the rearmost cell. Upon further forensics I determined, that this is not the first time it has been opened. I see toolmark "slips" on the flat surface of some of the brass. I was able to clean the cell with a lens wipe, suggesting that the dust and crud (thumb print?) came from the ham-fisted-ness of the previous owner.

    I assume the halo I see is either a failure of the coating, or if this in fact 2 cells together, one being convex and one being concave, then perhaps what I am looking at is the beginnings of "separation."

    What follows is the iris. It operates relatively smoothly, though there are no detentes. It also appears to have some substance on it, though it looks like rust, it feels a bit more like very old dry grease.

    From here I can access the rearmost aspect of the front cell. I believe this to be where my "spider webs" live. Funny, I can see a pattern here, but it doesn't look spiderweb like at all unless the rear cell is screwed back in. (Cool!) Reminds me of the toy with the parabolic reflector that let you see a button, but you couldn't press it, because it was down in the reflector.

    A swipe of the lens cleaning tissue removed some more cruft and a little air removed most of the dust. I felt the texture of the area that I was thinking to be fungus with the edge of my fingernail, and it does in fact have a texture that would suggest that it is either proud of the glass or has etched it.

    I will attempt to clean this with something a little more aggressive than this lens tissue, and perhaps some kind of lens cleaner or solvent? Either way, it is relatively minor and doesn't really show through when looking through the lens at something as opposed to looking askance into the lens

    Remember Dan, I am also trying to learn some rudimentary repair and service techniques as well as acquire equipment. So, obviously, I don't know what I am doing. But, I would rather not know what I was doing, and learn on a $1 lens than not know what I am doing and learn on a $700 lens.

    As for not buying anything until I learn more... the question comes to mind, "How will I learn more without having stuff to learn on?" Can I convince people to send me their junk gratis so I can take it apart and mess with it?

    In the front of the lens there are threads. There is a name plate that has all that writing I quoted in the earlier post. Is that physically part of the front cell or does that come out then the cell is screwed in behind it? I am guessing something like a suction cup on the glass of the lens would unscrew this, or do I have to use something wider to unscrew the "name plate" first?

    I am not intending to put this into a shutter, unless someone had said something like, "Those fit into a standard blurf." But I will cut me a board and try and mount it so I can see the image on my GG. It seemed to project an image of my double windows at 8 feet away into an image circle about 7" or 8" on my opposite wall from about 6 or so inches away at 4.5. Certainly no perfect test but impressive still to see the magic

    It would be nice to find a retaining ring to fit but worse comes to worse I will glue it to a board or put a big rubber band on it to hold it to a board. I can see how it does in my enlarger, too, or perhaps put it on the polaroid mp-4 to replace the little tominon I stole to turn that into a Frankenstein enlarger, or dedicated macro camera, Scheimpflug be damned!

    I am having fun, and hopefully I will learn something, if nothing else but what some of these things are called. Thanks for the luck, I think a buck for the paper weight is pretty lucky.

    Who knows, maybe after it is cleaned up, I can call it "Rare" and put it on eBay and send my kids to college

  4. #4
    Jim Noel's Avatar
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    Dismantle the lens and clean the elements with Listerine to kill and remove the fungus.
    [FONT=Comic Sans MS]Films NOT Dead - Just getting fixed![/FONT]

  5. #5

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    Thanks Jim! Are there any concerns I should have with the Listerine damaging anything else?

  6. #6

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    Absinthe,
    Boy, you can do lots of stuff with only a buck in it.
    The decorator ring should unscrew. That's the ring with the information on it.
    Then there is normally a thin ring with spanner notches holding the cells in place.
    You need to be aware of the orientation of the cells when you remove them. It's possible to reassemble some lenses with the elements out of order. In most newer lenses, not so likely(think lowest common denominator).
    If you have separation it's a good time to learn how to re-cement elements.
    The almost universal solvent, Acetone will get things apart for you, a small container to drop the group into & let it work for a day or three. Some of the early glass was pretty soft & I have broken an element by trying to rush the process. Only did that once & like you with a lens that was inexpensive.
    To recement a group, it's gotta be clean(acetone & lens tissue). Use "crystal Clear", it's a UV curing optical cement for-----gluing stuff like this together. Most Ace hdw. normally stock it.
    If you try this be careful using the CC it only takes one drop and you sure as hell don't want any air bubbles in it. Apply one drop to the concave element & carefully set the convex element in place and gently rub both elements together to spread the glue. Once the glue is spread, Do not separate the elements or you'll introduce bubbles, Align the elements, wipe the excess from the edges and expose to UV/sunlight. It takes about 24 hrs. to cure.
    I use two "V's cut into small pieces of hardwood to align the edges.
    BE careful with the alignment, The Crystal Clear is really permanent so if something is slightly mis-aligned it no longer fits into the barrel.
    The edges if the glass also have to be painted black after the glue dries, I've tried using a brush but the application is too thick and uneven. Black lacquer or enamel works with two or three LIGHTLY applied coats.
    Heavily sedated for your protection.

  7. #7

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    Now with only a minor amount of encouragement from my opposite thumbs I was able to unscrew the front cell (without even touching the glass ... mostly)

    For those that are following this thread the nameplate is integral to the front cell.

    So I have extracted the cells, and will treat them to some mouthwash later tonight. Is there any service to be performed on the iris? Other than being careful not to drop the barrel and spill all the little blades all over the place. There are so many of them the circle is almost a perfect circle...

  8. #8

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    Thanks John! This sounds like fun. I am not sure I have the "v-notch" image clear in mind yet though. As for the decorator ring, it is all connected to the glass. I am not sure how to describe this, but to start with there are no spanner notches or holes anywhere. The glass parts seem to be integrated into a threaded metal part (of which the decorator ring seems to be part) I can take digigraphs of this later.

    Ok, so the cells and iris are in the barrel. When I remove a cell, it has a glass component and a metal component (I assume the glass is glued into the metal) so I have been calling the combined glass and metal component a cell. It may have one or more "elements" in it? What is the metal part that holds the element groups/pairs/singles called once you removed the elements from the cell ( I assume by delaminating them with a solvent )?

    Speaking of solvents, what is your opinion of MEK? It is available and I was told it does the same as Acetone, but is less volatile and thus will not evaporate as fast (better for soaking?)

  9. #9
    juan's Avatar
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    You might also put the lens cells out in the sun for a day. The UV can help kill the fungus, though it won't remove anything that's there.
    juan

  10. #10

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    Absinthe, depending on the lens EKCo lenses' elements are held in by swaging or by retaining rings. Elements that are swaged in can't be extracted without ruining the lens; once removed they can't be replaced. Don't ask what swage means, look it up.

    Retaining rings can in principle be unscrewed.

    Trim rings (that's what they're called) are usually screwed in. They are usually removed with a rubber fixture that's essentially a rubber stopper with the center cut out so that it won't contact the glass.

    Depending on your lens vintage, its rear cemented doublet was glued with Canada balsam (soluble in acetone, also in the MEK you have) or by a uv-curing synthetic (known to be soluble in acetone, I'm not sure about MEK).

    If the diaphragm turns smoothly leave it alone unless you want the joy of ruining it. "Stuck" diaphragms are cause by gunk in the barrel, not by gunk on the leaves.

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