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  1. #1
    Worker 11811's Avatar
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    Zeiss Super Ikonta IV focus problem

    I have a Zeiss Super Ikonta IV. Everything works except the meter but that's not a problem. I have a Gossen meter that does the job.

    After shooting a few rolls I have noticed that the focus isn't always sharp. Sometimes it's blurry around the edges.

    I've been reading up and have found a couple of things that could give an answer but I'm looking for some confirmation.

    I read that you should not wind the film to the next frame until just before you plan to take a picture. If you close or open the bellows too fast, you create a vacuum that pulls the film out of the focal plane. Advancing the film AFTER you open the bellows puts tension on the film which ensures it lies flat in the gate.

    I'm not 100% convinced of that but it's easy enough to prove or disprove by experimentation. I'm running through a roll of film, right now, to test the theory.

    I also read that the rangefinder mechanism needs to be calibrated from time to time. It's easy enough to send it in for a CLA but I would, of course, like to avoid spending money unless it is necessary. (The camera is near mint. Probably only had a couple of rolls through it in its lifetime before I inherited it.)

    I'm pretty sure that the lens board is opening all the way and locking fully into position. The struts move smoothly and the bellows are in good condition.

    Strangely enough, the focus seems to be more out of calibration when set closer to infinity. That's sort of counter intuitive. Isn't it? You'd think focus is less critical when the lens is at infinity. Wouldn't you?

    I don't rule out the possibility that the problem lies, not in the camera, but in the idiot behind the camera.

    Rangefinder focusing just seems a bit finicky to me. You really have to pay attention and focus very carefully. I also have the bad habit of focusing then moving slightly before taking the shot. It's stupid but it's something I have always done, subconsciously, ever since I was a kid. I just have to buckle down and pay attention. Most of the time I can deal with it but, on a camera like this, my bad habits might be making the problem worse.

    So... Is it the camera? Is it me? Or, is this just par for the course with a folding rangefinder camera?
    Randy S.

    In girum imus nocte et consumimur igni.

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    http://www.flickr.com/photos/randystankey/

  2. #2

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    I read that you should not wind the film to the next frame until just before you plan to take a picture. If you close or open the bellows too fast, you create a vacuum that pulls the film out of the focal plane. Advancing the film AFTER you open the bellows puts tension on the film which ensures it lies flat in the gate.
    Yes, I do this all the time : first unfold the camera and then spool the film to the next frame and then do the settings and shoot. But not only for the reason you give, also because the "wind" generated by unfolding could sometimes lift some "dirt" inside the camera and settle it on the film (yielding "black" spots - opposite of white spots due to dirt on the neg under the enlarger - or the scanner).

    As for "focusing errors", are you sure that these actually are ? i.e. that what you want in focus isn't but some other plane is ? Because my experience of such MF folders (a Moskva V - russian copy of the Super Ikonta) is that most often, lack of sharpness is due to "microscopic" movements caused either by "my nervousness" or by tiny vibrations of the lensboard on shutter release (paradoxically, these vibrations may have a strong effect at the fastest shutter speed of 1/250, because the shutter springs of these old compur designs are then pulled very taut). To damp these vibrations, I use to hold both the lensboard (with one hand) and the body of the camera (with the other).

    Bye, Paul
    Last edited by polka; 09-04-2011 at 08:24 AM. Click to view previous post history.

  3. #3
    Worker 11811's Avatar
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    So, if I read you correctly, you're saying that these types of cameras are just finicky when it comes to the way they focus. Right?

    I can see where that can happen. With a larger format, a longer lens and a wider film plane depth of field/zone of focus can be a lot shallower, making focusing more critical. Since I grew up on 35mm SLRs with TTL focusing, I probably need to reprogram my brain to shoot with a rangefinder system. I'll just have to be more conscious about my focusing and pay attention to the scales more often. (i.e. If what I read on the focus/DOF scales doesn't jive with what my brain tells me should be in focus, I probably need to have the rangefinder adjusted.)

    I will also consider using slower shutter speeds to test your theory about vibrations caused by the shutter springs. I have been trying to stay at 1/125 or above because common sense tells us that we should use a shutter speed that is greater than the reciprocal of the focal length when we hand-hold the camera. I can try 1/60 on a tripod. I can also try steadying the lens with the hand to dampen vibrations.

    Maybe I just need more time to grok this rangefinder thing.
    Randy S.

    In girum imus nocte et consumimur igni.

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    http://www.flickr.com/photos/randystankey/

  4. #4
    MattKing's Avatar
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    The DOF scales may have been designed with contact prints or small enlargements in mind.

    The concern about opening the camera after winding would be more likely to affect sharpness at the centre than at the edges..

    Try it on a tripod or steady, flat surface to see if the problem is with camera movement.

    Is the edge sharpness more of a problem at certain apertures? If so, it may be an issue with the lens (excess spherical aberrations?).
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  5. #5
    Worker 11811's Avatar
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    I usually shoot at apertures between ƒ-8 and ƒ-11, avoiding ƒ-16 and ƒ-22 when possible. When shooting 400 speed film is is rarely necessary to go larger than ƒ-8 or ƒ-5.6.

    Basically, I try to stay away from smaller ƒ-numbers to prevent narrow DOF problems and I try to avoid larger ƒ-numbers to prevent diffraction around the aperture blades.

    The lens LOOKS clear around the edges. Although the camera is 55 years old, it is in good condition. It was stored in its original box with original packaging, additionally stored inside a military ammo box with the lid sealed shut. The ammo box was kept in the back of a closet in an upstairs bedroom of the house. This is probably as close to ideal as the average person can get. No?

    Unless there is something wrong with the camera that the average person can't easily detect, I'm pretty sure that it works as well, today, as it did when it was new. I have only put five rolls of film through the camera and have had very few problems at all. Counting the times I've used it, I can't imagine the thing has been fed more than a dozen rolls of film in its lifetime.

    The only thing wrong with it is that the meter doesn't read correctly. It works but reads a couple of stops low but, since I can't count on the error to be linear, I can't say, for instance, that the meter always reads N-stops low, etc. Instead, I just use a handheld. This is par for the course, given the camera's age. I don't see any reason to spend money repairing the meter unless there is something else wrong with it. At this point, I don't know for sure. As much as I would love to send the camera in for cleaning and calibration, I don't have the money to spend right now.

    If I could prove that there was something on the camera that needed to be fixed, I could see fit to give a higher priority to repairing it.

    What's a good way to test the camera? Run a roll of film through it, taking pictures of things like a picket fence from known distances, with different combinations of shutter and aperture then analyze the resulting negatives?
    Randy S.

    In girum imus nocte et consumimur igni.

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    http://www.flickr.com/photos/randystankey/

  6. #6
    MattKing's Avatar
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    Quote Originally Posted by Worker 11811 View Post

    What's a good way to test the camera? Run a roll of film through it, taking pictures of things like a picket fence from known distances, with different combinations of shutter and aperture then analyze the resulting negatives?
    Yep, that is a good method.

    As in something like the attached.

    Focusing tests should involve both large and small apertures.

    If you have access to good E6 processing, it will give you the most accurate check on exposure.
    Attached Thumbnails Attached Thumbnails focuscheck1b.jpg  
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  7. #7
    Klainmeister's Avatar
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    If it's the Tessar lens, then it will not be sharp until about f/11 and higher towards the corners of the 6x9 negative. You'll find that it behaves like a 6x7 when opened up and then a 6x9 when stopped down in terms of corner-to-corner sharpness. I've dealt a lot with these cameras as a backpacking companion and can say that was a very common experience with many different brands and lenses.

    Outside of advancing the film in the methods aforementioned, also be absolutely certain that the lens and shutter is parallel to the film. I've seen a many that it ever so slightly isn't completely parallel and makes both ends slightly out of focus.

    Lastly, if it is a problem with the RF, they're quite simple and I could email you instructions on that. I've taken apart and rebuilt close to ten 6x9 folders, including that model.

    Best bet: Tessar lens design.

    That's just my $.02
    K.S. Klain

  8. #8

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    Super Ikontasmuse front cell focusing - when you focus, you only move the front most cell of glass compares to other cameras where the entire lens moves (or the paper moves ala the Mamiya Six rangefinders). Front cell focusing involves a sharpness compromise either in close or far away. On my SI IV (and normal ones as I understand it) the camera is shaper at infinity than it is when near focused. Mine is very soft when shot wide open with a near by subject and I haven't found a lens adjustment which can fix this.

    A few tests to narrow down you issue.

    First, when focused at infinity and looking at something really far away, do the images line up? If not, I'd take a look at why before dong anything else. The rangefinder may simply be off.

    If it is accurate, I'd move on to checking the lens. Open the back of the camera, and price of frosted glass, tape or something else which will show you the projected image in place against the back of the camera. Set the camera to B and try focusing near and far. When is and isn't it in focus? This should generally match the results you see while shooting. If this looks off , the lens itself may need to be adjusted.

    Just keep in mind that something is going to be soft due to the lens design and how they implemented focusing.

    Edit: Yes, you generally need to be shooting at a higher shutter speed than smaller formats to deal with camera movement blur or using a tripod. I try to shoot at leat as 250 when possible. Note that different rules apply for the Moskva cameras as the shutters themselves generate shake at the highest shutter speeds.

  9. #9

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    Not only the Moskva, all the folders with old design Deckel Compurs. I own a Rodenstock Citonette : a 645 folder dated 1934, with 75mm/2.9 lens mounted on such a shutter and am often disappointed with pictures taken at 1/250, even when holding them in my special way, with both hands - 1/100 and lower speeds seem OK.

    And I agree strongly with this :

    be absolutely certain that the lens and shutter is parallel to the film. I've seen a many that it ever so slightly isn't completely parallel and makes both ends slightly out of focus
    I had several folders which I had to adjust for this !

    Paul
    Last edited by polka; 09-05-2011 at 08:00 AM. Click to view previous post history.

  10. #10
    Worker 11811's Avatar
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    Quote Originally Posted by Brian Legge View Post
    Super Ikontasmuse front cell focusing - when you focus, you only move the front most cell of glass compares to other cameras where the entire lens moves (or the paper moves ala the Mamiya Six rangefinders). Front cell focusing involves a sharpness compromise either in close or far away. On my SI IV (and normal ones as I understand it) the camera is shaper at infinity than it is when near focused. Mine is very soft when shot wide open with a near by subject and I haven't found a lens adjustment which can fix this....

    ...

    ...Just keep in mind that something is going to be soft due to the lens design and how they implemented focusing.
    So, then, it seems like you are saying that I'm expecting more from this camera than it was designed to give. No?

    That doesn't mean I am overly disappointed but I need to adjust my expectations.

    I am still doing my tests. The weather has been cloudy in the last few days. I've got a few more shots that will have to wait until it is sunny outside.

    In the mean time, can anybody tell me what I should expect? What market, what kind of photography was this camera aimed at?

    Tourist and vacation shots, etc.?
    Randy S.

    In girum imus nocte et consumimur igni.

    -----

    http://www.flickr.com/photos/randystankey/

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