Correcting for parallax

Discussion in 'Rangefinder Forum' started by pstake, Apr 14, 2013.

  1. pstake

    pstake Member

    Messages:
    715
    Joined:
    May 5, 2005
    Shooter:
    Multi Format
    After years of shooting with SLRs, I got bit by the rangefinder bug. Started with a Contax IIa with the F2 Sonnar and ended with that plus a Retina IIIc, F2 Xenon; Walz Envoy 35; Karat 36, F2 Heligon; and a Kiev IIa with what could be its original Jupiter-8 (both 1956.)

    They all have their charms but the Contax and Kiev are the most fun.

    The problem is: I have yet to master framing on a rangefinder after all those years of seeing exactly what the film sees. Some of these cameras seem to be closer to correct than others, in particular the IIa and the Walz. Not sure why ... but the Walz does have a frame line.

    I'm thinking that has something to do with this so-called "parallax correction."

    I've googled that term a few times and still don't have a solid understanding of what it is.

    Here are two recent prints from negatives made with the Kiev IIa and Jupiter-8 ... they clearly show my folly in framing.

    Any info about parallax correction, or tips / rules-of-thumb about adjusting the frame to correct for the difference between the viewfinder and the lens, is appreciated!

    Cheers,
    Phil

    ps. you should all go buy the SLRs i have listed in the classifieds. I'll make you a deal on both! After my rangefinder binge, I need to thin the SLR herd.

    img837_1.jpg

    As you can see, I cut off their hands. My original framing included their hand and moved their faces farther right.

    img838_1.jpg
     
  2. cliveh

    cliveh Subscriber

    Messages:
    4,714
    Joined:
    Oct 9, 2010
    Shooter:
    35mm RF
    Unless you are quite close parallax is not usually a problem, but some rangefinder cameras will correct for that as you get closer.
     
  3. Aron

    Aron Subscriber

    Messages:
    262
    Joined:
    Aug 27, 2009
    Location:
    Hungary
    Shooter:
    Multi Format
    It's easy to make a test for example with a bookshelf as your subject. Centre your camera and look in the viewfinder with your eye centered, and mark where the four corners of the finder are with small, but easy to see objects/Post it notes, etc. on the bookshelf. Take a photo, develop your film and check the results. This will show how much deviation there is in the system at the distance you focused. I check parallax at the closest focusing distance. You'll get used to correcting your framing at close distances in a very short time.
     
  4. Dr Croubie

    Dr Croubie Member

    Messages:
    2,015
    Joined:
    Mar 21, 2013
    Location:
    rAdelaide
    Shooter:
    Multi Format
    Just as easy as Aron's method, but doesn't require you to waste a film. Same thing, just leave the film out, open the back door, set to Bulb and open the shutter (cable release with locks are good to have). Grab a focussing screen from an SLR (if you don't have one lying around you can get one for a Canon or Nikon FF (d)SLR from fleabay for $10. Gently hold the focussing screen over the hole where the film would normally sit, and you can see the entire image as would be captured on the film, with the added advantage of swapping back with the viewfinder in real time. (just make sure your shutter doesn't close while you're working, if it closes you might break it.)
     
  5. Yashinoff

    Yashinoff Member

    Messages:
    193
    Joined:
    Sep 18, 2012
    Shooter:
    35mm
    What camera were you using for the example pics?

    Parallax correction basically works by having framelines in the viewfinder - which move towards the lens the closer the lens is focussed. So this "corrects" parallax, or more accurately compensates for it in the viewfinder.

    Many older RFs without compensation simply show less of the image than there is actually going to be, this helps minimize cutting things off due to parallax - but also means sometimes you get things in the edges of the photo you didn't count on!
     
  6. elekm

    elekm Member

    Messages:
    2,059
    Joined:
    Sep 12, 2004
    Location:
    New Jersey (
    Shooter:
    35mm RF
    Phil,

    Two thoughts here:

    - Don't frame so tightly. That will help to allow for parallax. Of course, that goes against our instinct, especially if you've been shooting with SLRs. I have this same issue with a Super Ikonta 6x9, and I have to remember to correct for vertical parallax when shooting anything closer than about 10 feet or so.

    - Try an external viewfinder. Zeiss Ikon made a turret finder for the Contax IIa. It's a bit costly, however, it does allow you to correct for vertical parallax, and the way it's constructed, it centers the eyepiece over the lens, which means that it automatically corrects for horizontal parallax. The downside is that this viewfinder is a bit costly. It generally sells for about $225, but sometimes you can chance upon a good deal and get it for less. The Soviets made a version that is identical to the prewar turret finder made by Zeiss Ikon. The location of the accessory shoe for the Kiev / Contax II and the postwar Contax IIa is different, and that's why it's best if you use the correct finder for the camera that you'll be using.
     
  7. pstake

    pstake Member

    Messages:
    715
    Joined:
    May 5, 2005
    Shooter:
    Multi Format
    Thanks for the suggestions. I actually own the pre-war Zeiss turret finder and it works fine. I also have the external finder for the Retina. But in both cases, the finder takes away from the simplicity of using the camera.

    All of your explanations do help me better understand how the finders correct for parallax, so tht i hopefully I can mentally do it a bit better in the future. Thanks for the responses.

     
  8. Bill Burk

    Bill Burk Subscriber

    Messages:
    4,984
    Joined:
    Feb 9, 2010
    Shooter:
    4x5 Format
    Hi pstake,

    Rule of thumb that you can use immediately; If you don't correct for parallax, you'll cut their heads off when you move in close.

    That's one of the reasons to love Leica (and other cameras where the framelines move appropriately).
     
  9. benjiboy

    benjiboy Subscriber

    Messages:
    8,540
    Joined:
    Apr 18, 2005
    Location:
    U.K.
    Shooter:
    Multi Format
    I have a Contax 11, a very similar camera that I've used for more that forty years,and the answer is practice, practice, practice until it becomes second nature.
     
  10. pstake

    pstake Member

    Messages:
    715
    Joined:
    May 5, 2005
    Shooter:
    Multi Format
    This is kind of what I thought the answer might be. Practice, I shall.

    Thanks for the responses, everyone.
     
  11. E. von Hoegh

    E. von Hoegh Member

    Messages:
    3,925
    Joined:
    Sep 14, 2011
    Location:
    Adirondacks
    Shooter:
    Multi Format
    This is a pretty good article on parallax http://en.wikipedia.org/wiki/Parallax
     
  12. narcosynthesis

    narcosynthesis Member

    Messages:
    2
    Joined:
    Apr 22, 2013
    Shooter:
    35mm
    Parallax is the issue caused by using optics in slightly different positions for viewing and taking a photo.

    With an SLR (or other 'through the lens' system) you use the same optics (ie the lens) for both composing and taking the picture, so the image recorded on the film is exactly the same as the image seen in the viewfinder.

    With a rangefinder (and also with cameras like a twin lens reflex) you use separate lenses for each job - so one lens mounted on front of the film for recording the image, and a viewfinder for composing it. Because these two lenses are slightly offset from each other they will see slightly different images. At long shooting distances this makes little difference, as the offset is essentially negated by the subjects being further away. At closer distances though the viewfinder being slightly offset means you are going to end up looking over the shoulder of your subject in the viewfinder.

    Some cameras will correct for this and move the frame lines as you focus closer, some won't and will just require you to mentally adjust. After you have shot a few rolls of film and see the results you should find yourself being able to tell when parallax will be an issue, and adjust appropriately.