Halation

Discussion in 'Beginner Questions' started by markruskikh, Feb 18, 2021.

  1. 5EE0B7DC-F3D1-42A2-824A-FB81ABEF1608.jpeg Dear all,

    I’ve recently got scans back from the lab, and I have some halation around highlights in high contrast scenes. See attached.

    can someone tell me what can be causing it and how to reduce it?

    photos were shot with Mamiya Rb67 pro SD, and a 127mm K/L lens. With portra 400, rated at 200. 62D1CD12-95FB-4254-86D1-518A5C9F8AE8.jpeg The day photo was shot at about f11, and the night one is almost wide open f5.6 as I wanted to avoid cars getting in the frame hence faster shutter speed.
     
  2. It might be lens flare .... see what other members say about it
     
  3. Internal haze perhaps - look through the lens with a flashlight. It could also be condensation formed on the lens surface from moving between cold and warm environments.
     
  4. FWIW, this doesn't look like halation, properly speaking.

    I like the 'flare' possibility, too
     
  5. it does seem like there is a thin layer of haze in the back lens element internally. Wasn’t aware that it can cause such a dramatic effect in high contrast scenes.

    Will have my Lens serviced.

    Thank you.
     
  6. You get a similar effect if there's a light mist or condensation on the lens.

    This can be from simply placing a warm hand next to a cold lens, or just from moving the lens from a cold environment to a warm one. It sometimes takes a long time to clear unless you can warm the whole lens up.
     
  7. Maybe it's not the fault of your lens. I've seen the same effects from scanners. They can have dirty lenses, too. Check to see if the "flare" appears on your negatives.
     
  8. Flared scans from negative film would tend to spread the shadows into the highlights. Not the highlights into the shadows as is happening above.

    "With portra 400, rated at 200."
    Of course, overexposing the film isn't going to help either.
     
    Last edited: Feb 20, 2021
  9. Dear all,

    Little update on the issue. the rare element of my lens seems fogged (pictures attached). 12A9A35F-1804-4386-82F6-070663E9F18F.jpeg DF434579-67C4-4479-B5C3-2E936706AC2C.jpeg

    Not very noticeable looking through the lens however when using a flashlight the whole rare element glows beyond any kind of transparency.

    I’ve got mixed feedback from my local camera repair stores, some said fungus, some said haze- which I tend to agree more with as it was my initial assessment as well. The only thing I fear if it is lens separation as I have no idea how to fix that.

    anyways, all of them refused to service a lens with anything like this, I guess in Brussels it doesn’t go beyond cleaning dust.

    So I’m waiting for the lens spanner wrench to come from Amazon and will dig in the rare element with some ammonia and hydrogen peroxide being handy.

    let me know if anyone dealt with the same issue.
     
  10. did few more rolls rated at box speed and scanned at different labs, and flare was consistent throughout all.
     
  11. Find out how the lens comes apart before messing with the spanner. That's often not the tool you start with, though in this case it might get you to the worst of the problem.
     
    Last edited: Feb 23, 2021
    markruskikh likes this.
  12. It's not fungus or cement separation. So you can relax on that fear.

    It's probably an oil haze, caused by the volatile component of lubricant(s) in the shutter or helicoid evaporating and then condensing inside the lens.

    Once the lens is apart, the haze should rub right off. Not quite as simple as that - it'll probably need some alcohol solvent - but not a difficult job either.

    Any 'repairer' that feels they can't tackle such a simple job really doesn't deserve the name. Look further than your crappy local camera store. They obviously don't know what they're doing!

    It looks as if the rear section of the lens needs to be completely stripped down. About 10 minutes work at most for someone with the right tools and skill. Cleaning; another 20 minutes, and rebuilding the lens 5 minutes. An hour's labour and the price of a couple of lens tissues should cover the cost easily.
    No!
    No, no, no!

    Get some proper alcohol-soaked lens tissues and some dry ones. That's all it should take.
     
    Last edited: Feb 25, 2021
  13. thank you for your post, I’ve taken the lens apart and the worst fear turned true, the problem is in between the two cemented elements in the rare double. A9A8AE68-57B1-4897-8DC6-B53AFD09C9BC.jpeg
     
  14. Oh wow! That's a new one.
    The lensmaker must have used a synthetic cement that deteriorates and turns milky over time.

    I've come across a few lenses that use plastic elements - Canon and Sigma are the main culprits - where those plastic elements develop an irremovable surface haze. Apparently caused by micro-crazing of the plastic surface.

    Never seen a cemented doublet go milky before though. And it appears to have a UV fluorescence.

    Can you be sure that the lens hasn't been tampered with by a previous owner? This might be a one-off DIY recementing job, using superglue or some such.
     
  15. Crazy!
     
  16. I suspect it is all of the above, but mostly it is having a very bright light source in frame.

    More commonly it is having the sun in frame, indoor available light might have actual
    light bulbs. But the neon sign is very bright, relative to the rest of the scene.

    You mention the EI change, but not how you metered it. An averaging meter,
    or a spot meter pointing the wrong way, will expose for the sign and underexpose
    the rest. Matrix metering might figure it out.

    But yes, the reason for antireflection coating on lenses is to allow for shots
    like this, but it is never perfect. The direct light from the sign is many stops
    brighter than the inside of the store. This is not so obvious in film, where it
    saturates, and also for the eye, which can partially adapt to the difference.

    Otherwise the traditional meaning for halation is rings around small point sources,
    as reflection from the back of the film, or the pressure plate behind the film.
     

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