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Thread: Focusing a TLR

  1. #21
    36cm2's Avatar
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    Ok, let's see.

    Rolleiflexible, I agree with you that if the OP's photos are consistently out of focus then the problem is unlikely film bulge. I have experienced film bulge on my folder and I believe I've also experienced it on my Rolleiflex, but it's not the type of problem that presents itself consistently. I mentioned my conversation with Ken as advice that I've found helpful in dealing with film bulge, not as the solution to the OPs problem. I should have been clearer on that, but the other posters' advice on checking focus was already adequate. I think the OP's lenses are either incorrectly focused (although I've had my Rollei serviced by Krimar and he's done great work) or his focus technique is flawed. After reading this thread I'm pretty sure that my focus technique with the Rolleiflex is flawed and can be improved.

    Q.G., I disagree that bulges don't pop. I didn't get into the details of my conversation with Ken for fear of misrelaying his comments, but I believe he was saying that acetate film base is deformed by any curl feed rolling system and will have a tendency to bulge toward the lens following that deformation. Tensioners in an advance system are designed to restrict that tendency, but high humidity and temperature exacerbate the tendency and when you advance the film you expose the film more directly to those elements. In his experience, it only takes about a minute for those elements and any slip in the tensioning system to allow the recently induced bulge of the film base to pop. So, if you can minimize the amount of time that film has to bulge right after being advanced, that's helpful. Don't confuse this with a situation where you have left a camera with film in it idle for a long period. In that case I advance two frames before shooting, because you're sure to have a strong memory-induced bulge from the film sitting on the rollers. Some cameras have their rollers spaced so this type of bulge lands outside of the film exposure area when advanced, but I don't know if the Rolleiflex is one of them.

    Sorry for the long-winded response. To put this all in perspective for the OP, check your camera's focus again with the great advice others have left. Don't worry about film-bulge. Shift happens.
    "There is a time and place for all things, the difficulty is to use them only in their proper time and places." -- Robert Henri

  2. #22
    Rolleiflexible's Avatar
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    Quote Originally Posted by 36cm2 View Post
    Another vote for the Rolleiflex on a tripod. It's even sexier with legs.
    By coincidence I came across this photograph
    by Jan Scholz over on Flickr:

    http://www.flickr.com/photos/micmojo/4424757937/

    Jan seems to have confirmed your observation. :-)

  3. #23
    Shawn Dougherty's Avatar
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    Alright! =)

  4. #24

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    Thanks for all the posts, guys. I have taken and processed another roll, which looks better, but I need to scan. I have been taken out of my photo activities lately by other pressing needs, will post scans when I can.

  5. #25
    ic-racer's Avatar
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    Quote Originally Posted by Rolleiflexible View Post
    If you look at
    the film path of a Rolleiflex TLR (as opposed
    to, say, a Rolleiflex SL35), you will quickly
    realize that film bulge isn't going to happen
    in the TLR models.
    Film bulge does happen with Rolleiflex TLRs. In fact they made a glass plate that fits in front of the film to eliminate the problem.

    The problem was eliminated in the motorized 6x6 SLRs with the vacuum back.

  6. #26
    Slixtiesix's Avatar
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    Yes, it does happen but only if one had left the film in the camera for days, and even then it would only affect the image that directly follows. Zeiss recommends to skip this image in the case that absolute sharpness is needed. If you load the film and shoot it immedeately within some hours, film bulge is no problem, neither with Rollei TLRs nor with Hasselblads or other mf-cameras.
    The mentioned glass plate was used in some Rollei TLRs in the 50s, but Franke&Heidecke abandoned it after a short time, because it only made a very minute difference and easily attracted dust and the like. Improvements of sharpness were only visible at full aperture and even then they were very small.

    Best Regards, Benjamin
    Last edited by Slixtiesix; 04-04-2010 at 03:41 PM. Click to view previous post history.

  7. #27

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    Quote Originally Posted by Rolleiflexible View Post
    I'm sorry. If the camera is consistently out of
    focus, I will bet my apartment that it is not film
    bulge. I have shot, literally, over 10,000 rolls
    through an assortment of Rolleiflexes, including
    two Tele Rolleiflexes, of people close-up, and
    nearly all at wide apertures, and it is the rare
    roll that is not perfectly focused on the irises of
    my subjects' eyes -- and that is so whether the
    eyes are in the center of the frame or at the very
    edge.
    May I say that those are some really amazing portraits. Superb work there!

  8. #28
    Rolleiflexible's Avatar
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    Quote Originally Posted by ic-racer View Post
    Film bulge does happen with Rolleiflex TLRs. In fact they made a glass plate that fits in front of the film to eliminate the problem.
    As another poster already noted, the glass
    plate does not prove your point.

    Have you observed this "film bulge" occurring
    in a Rolleiflex TLR? Have you worked at any
    length with a Rolleiflex TLR? How does the
    problem manifest, in your experience? Can you
    post examples of negatives made with a Rolleiflex
    that exhibit "film bulge"? If you cannot answer
    these questions "yes" and provide examples, I
    will conclude that my own experience with the
    cameras is typical, and that you argue from
    hypotheticals and hearsay.

  9. #29

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    Wow - interesting discussion about film bulge and glass plate, neither of which I was ever aware of.
    I'm reactivating the thread (reviving a slumbering horse) with a simple question. My life has been busy and it's taken me this long to resume testing. I have confirmed the focus error with careful focusing (with a Scheider classic 4x lupe), and found that personally, my best focus is with the magnifier (the one that hinges to the hood) and my naked left eye.
    I did a careful (yes, tripod mounted) test with film loaded and shot within 1/2 hour and determined that the camera, at near the closest focal point, wide open, focuses an inch or two behind on the film, relative to where I focus on the glass.
    My question: This means that the ground glass is too far from the viewing lens, right - as opposed to too close? (assuming parallel between the lenses hasn't been compromised).
    I should add that this has never been a problem before the CLA (mentioned at the beginning of the thread).

  10. #30

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    George, your first post suggested the error was greater than an inch or two, but yes, if the screen is too high it will cause this fault. If the front standard tilts forwards (downwards) as it racks forwards - same result. A slightly displaced lens cell in either lens could allow both lenses to be (roughly) in agreement at infinity but not at close focus, or vice versa.
    I'm not clear whether you used the loupe instead of the WLF magnifier - or at the film plane with a ground-glass. If the latter then you should by now know exactly the extent of the problem and whether it's affected by any looseness of the focus mechanism.
    Setting the screen/lens/film plane for infinity focus is adequate for SLR's but TLR's also need checking for close-focus agreement between screen & film plane.
    Is the repairer who carried out the CLA aware of your concerns yet?
    I would have wished to be.

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