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Thread: Uncoated lens

  1. #1
    ziyanglai's Avatar
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    Uncoated lens

    Hi guys, I have a Wollenstak Rapax 135mm f/4.7 4x5 and also a 105mm ( I believe?) Schneider lens on my Franka Rolfix 6x9. Both are uncoated. I have not really seriously print using the MF film. But I recently had someone professionally printed an 8x10 on Ilford RC with a photo shot on the uncoated 4x5 and I notice that it is a little soft.. Is this caused by the uncoated lens? Would it help to reduce flare and increase sharpness if I hold a coated UV filter over the lens every time I shoot? Or would that not do anything? I also shoot 4x5 slides with the uncoated lens as well, but I usually scan those and can easily sharpen them so that's not a problem.. But with B&W I would like to print in the darkroom.

    Thanks all.


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  2. #2
    Hatchetman's Avatar
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    I believe my Wollensak 135mm is coated. It is very sharp and has plenty of contrast at f16. not sure Maybe there were earlier versions?

  3. #3

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    The filter won't do anything for reflections internal to the lens. Using a lens shade will help as will not shooting into strong light.

    Softness could come from many sources, anything from a characteristic of the lens, to some flaw like not being correctly fitted to the shutter or internal cloudiness from lubricants or 70-ish years of temperature and humidity cycling.

    A lens doesn't have to be coated to be sharp, but it helps.
    Mostly, so I understand, coatings improve contrast which does help with apparent sharpness.

  4. #4
    ziyanglai's Avatar
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    This is the one that I have and it is uncoated.


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  5. #5
    ic-racer's Avatar
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    Quote Originally Posted by ziyanglai View Post
    little soft..
    "soft" has two prominent meanings on this forum.

    SOFT as in HARD vs SOFT contrast. ie low contrast
    SOFT as in blurry, no sharp edges, fuzzy

  6. #6

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    Your raptar is coated. The little W in the C shaped circle denotes coating. These are single coated and might be more subtle than what you are used to.

    These will be a bit softer wide open but do sharpen up nicely by f16 certainly. You might have a bad example or it has issues - make sure the doublet cells are installed correctly and that both front and rear are fully threaded into the shutter.

    Dan

  7. #7
    Hatchetman's Avatar
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    It is my understanding that all Raptars are coated lenses.

  8. #8
    ziyanglai's Avatar
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    Maybe it's coated in the back.. Cause I don't see the coatings in the front element.. And "soft" as in blurry, no sharp edges. Even at f/32.


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  9. #9
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    If you were to remove the lens with board from the camera and hold it at an angle to a bright light source you will notice it has a slight blue or purple case to both the front and rear cells. The tint is the lens coating. As others have said this is a single coated lens as opposed to several coating layers on the front element. The coating or number of coating layers is not the cause of lack of sharpness.

    Are you shooting hand held?
    What shutter speed?

    Place the camera on a solid tripod and use a cable release to check the sharpness. Some tripods transmit vibration from any source to the camera causing a lack of sharpness. Some camera bodies are not capable of making critically sharp photos, that is why they were labeled amateur cameras when new.

    The shutter running rough can be causing the problem also.

    The lens is a f4.5 reduced to f4.7 and is described in this Wollensak catalog:
    http://www.cameraeccentric.com/html/...llensak_3.html
    Last edited by shutterfinger; 05-28-2014 at 10:31 PM. Click to view previous post history.

  10. #10

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    coating the lens doesn't make it sharper -- coating just reduces the amount of light reflected off the surface of the glass. If your image is soft all the time, not just one sample, seek the cause elsewhere. The advice to use a tripod, cable release, and even lighting, is wise.

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