Pinhole Mamiya RZ67 & Polaroid? Basic Questions!

Discussion in 'Alternative Processes' started by Magpie, Jan 24, 2006.

  1. Magpie

    Magpie Member

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    Penrith NSW
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    Hi,

    In a weak moment I purchased a Mamiya Body Cap Pinhole and a 'Pinhole Factory Exposure Calculator' on ebay.

    After reading the various threads here I have rough idea how to take some pinhole photos with my Mamiya, and given that I have a few packs of soon to be expired Polaroid colour & B&W film I was considering experimenting.

    With the colour polaroid is there a reciprosity factor I need to add to my exposures?

    Also can anyone explain how the #$^&*( the Exposure calculator works? It has time on the outer ring and f numbers on the inner ring. Is there something missing - the pinhole size? or am I missing the point entirely?

    I will be getting a book from the Pinhole Resouce centre but wanted to try some first experimants this coming holiday weekend - 4 days off work!

    Thanks

    Brendan
     
    Last edited by a moderator: Jan 24, 2006
  2. Pinholemaster

    Pinholemaster Member

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    I see no weakness in your purchase. Have fun with it. There is always a little reciprocity failure with all film at such long exposures, but don't worry, a little overexposure of Type 55 never hurts. I don't use any formulas - just trial and error. At most I've ever had to extend an exposure is about a minute for a 5 minute exposure. In the 10 secs to a minute exposure range, the RF is in the seconds in my experience.

    I use a "Black Cat" exposure guide. Most meters don't have an f/stop range of a pinhole camera. I take an exposure reading, say 1 sec at f/64. I set the guide at that reading. Then I go to the aperture of the pinhole, say f/256, and look up the new exposure time - 30 sec. Easy as that.

    All you need to do it look up the f/stop number of your pinhole body cap. My Nikon pinhole body cap is f/185.

    Hope this is helpful. My web site shows a lot of pinhole photography (www.walterpcalahan.com) if you go to the experimental button on click on PinholeDC.


     
  3. waynecrider

    waynecrider Member

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    :tongue: Did the same and picked up a pinhole cap for my Mamiya 645. Just got a roll back that had a few exposures on it and I can see that more experimentation is in order, but I did get a couple of interesting exposures. I think with a pinhole the subject matter and especially the framing are very important. To me it seems, just from this roll, that you need to concentrate attention on less subject matter then more. My pinhole landscapes were no big deal, seemingly just misfocused frames whereas cropping the image down and concentrating on less subject matter imparted more of an ambience to the image.

    Here's a link to a resource to determine exposures for your particular pinhole size. Print it out and carry it on you. http://www.mrpinhole.com/calcpinh.php