Site Sponsors
Results 1 to 11 of 11

Thread: Contax / P1 users: What is the preferred workaround for long exposures?

  1. #1
    Senior Member
    Join Date
    Feb 2009
    Location
    Scottsdale, AZ
    Posts
    484
    Post Thanks / Like

    Contax / P1 users: What is the preferred workaround for long exposures?

    My research has turned up several methods of working around the 32-second limit, but it's not clear which of these is "the best" method in practice. How are you accomplishing this?

  2. #2
    Senior Member
    Join Date
    Jun 2009
    Posts
    1,347
    Post Thanks / Like
    Images
    12

    Re: Contax / P1 users: What is the preferred workaround for long exposures?

    as I also shoot a tech camera I do have a so called "wake up cable".
    So I use the back as on a tech camera. To achieve this I simply put a sheet of thin paper on the contacts of the back before attaching it to the Contax. This way there is no communication from camera to back and vice versa. In other words: the back doesn't know whether it's attached to a Contax or a shoe box.
    Form then on I operate camera and back like working with the tech camera... i.e.:
    - wake up cable connected to the flashsync of the Contax
    - activate the back via the wake up cable
    - release camera in B-mode
    - close shutter of the camera
    - de-activate the back via wake up cable (not quite sure anymore if this is necessary but it any case it won't hurt)

    (it's a while ago I've done this... hopefully I remember it correctly. In any case it works with the wake up cable and a sheet of thin paper...)

    edit: what are the other workarounds you've heard of?
    Last edited by thomas; 13th August 2010 at 13:44.

  3. #3
    Senior Member
    Join Date
    Feb 2009
    Location
    Scottsdale, AZ
    Posts
    484
    Post Thanks / Like

    Re: Contax / P1 users: What is the preferred workaround for long exposures?

    I should have chosen my words more clearly, as the workaround I referred to is essentially the same in each case and itís only the various methods of implementing it that differ.

    For instance, thereís the method you describe using a wake-up cable and also a similar double-push approach that instead uses a universal shutter release with a sub-mini jack that plugs into the P1 multi-port adapter. Then there is the Kapture Groupís multi-exposure box, which separates the double-push into separate pushes of separate buttons, and lastly, thereís also their double-cable release, which requires but a single push of a button to execute the double-push method.

    So, the question I intended to ask is which of these implementations have you chosen and what was the reason you chose this approach over the others? Each of them requires a slightly different combination of bits and pieces and while the minor differences in price between them are easy enough to quantify, itís more difficult to determine whether one of them works better in the field than the others hence my request for feedback.

    Thanks for your input, btw!

  4. #4
    Senior Member
    Join Date
    Jun 2009
    Posts
    1,347
    Post Thanks / Like
    Images
    12

    Re: Contax / P1 users: What is the preferred workaround for long exposures?

    Quote Originally Posted by Audii-Dudii View Post
    So, the question I intended to ask is which of these implementations have you chosen and what was the reason you chose this approach over the others? Each of them requires a slightly different combination of bits and pieces and while the minor differences in price between them are easy enough to quantify, it’s more difficult to determine whether one of them works better in the field than the others hence my request for feedback.
    okay, as they are all based on a wake up cable in one way or another I'd simply go for the "cheapest" solution (i.e. the standard wake up cable). When you are shooting long exposures any comfort in handling is actually overdone, no?
    "Cheap", btw, is a bit misleading... these cables cost around €120 or so. When you order it you might think they will ship a golden cable with an ivory button. But it's simpy a trivial cable...

    Your Phase back contains (should contain) a little cable that you can use to release the Contax from Capture One (when shooting tethered). I think you can use that one and just need an adapter and a second cable that has a release button and the flashsync connection. But I am not quite sure.

    If you have a "+" back it will display the exposure time... so you don't have to carry a timer or watch for the exposure time. Quite handy...

  5. #5
    Subscriber gogopix's Avatar
    Join Date
    Nov 2007
    Posts
    1,383
    Post Thanks / Like

    Re: Contax / P1 users: What is the preferred workaround for long exposures?

    The Dalsa Phase backs work without wakeup, just the synch cable eg from Alpa/Schneider to Phase that works with zero latency. I have not tried with Contax (Doug may know) but it may be as simple as using same cable (blocking Contax contacts to Phase) and B expose.

    Would that work, Doug?

    Victor

  6. #6
    Senior Member
    Join Date
    Jun 2009
    Posts
    1,347
    Post Thanks / Like
    Images
    12

    Re: Contax / P1 users: What is the preferred workaround for long exposures?

    Quote Originally Posted by gogopix View Post
    The Dalsa Phase backs work without wakeup
    they also work without long exposure

  7. #7
    Senior Member
    Join Date
    Feb 2009
    Location
    Scottsdale, AZ
    Posts
    484
    Post Thanks / Like

    Re: Contax / P1 users: What is the preferred workaround for long exposures?

    Quote Originally Posted by thomas View Post
    they also work without long exposure
    LOL ... true, that. FYI, mine is a P30+ and I'll be using it for nighttime photography with exposures in the 30-second to 6-12 minute range. It just arrived back from getting "new shoes" (i.e., a mount swap) earlier this week -- many thanks to Steve from C.I. for facilitating this for me! -- so I'm still early in the process of familiarizing myself with it ... so far, so good, though.

  8. #8
    Senior Member
    Join Date
    Jun 2009
    Posts
    1,347
    Post Thanks / Like
    Images
    12

    Re: Contax / P1 users: What is the preferred workaround for long exposures?

    Quote Originally Posted by Audii-Dudii View Post
    LOL ... true, that. FYI, mine is a P30+ and I'll be using it for nighttime photography with exposures in the 30-second to 6-12 minute range. It just arrived back from getting "new shoes" (i.e., a mount swap) earlier this week -- many thanks to Steve from C.I. for facilitating this for me! -- so I'm still early in the process of familiarizing myself with it ... so far, so good, though.
    You won't be disappointed... that is for sure. The Contax is a joy to use.
    Steve certainly knows everything about it... I guess (don't know him) ... and can tell you which cables you'll need. Or Doug. Maybe also Yair steps in... he always knows some secrets about the Contax...

    BTW: "thin" sheet of paper means really "thin". Cut out something from a lens cleaning paper or so...

  9. #9
    Workshop Member
    Join Date
    May 2008
    Location
    NYC
    Posts
    3,275
    Post Thanks / Like
    Images
    7

    Re: Contax / P1 users: What is the preferred workaround for long exposures?

    My personal favorite is the Kapture Group Box because often long exposure photography is done in the dark (duh) and having a medium sized box (as opposed to a small cable) which is easy to find, with two easy to find/use buttons (technically one button and one toggle switch) is hard to mess up.

    Note that the 2-shot cable would not work in this setup as the back would never receive a second signal. This cable relies on the flash sync of the lens to provide the second signal and since back/body communication has been severed the back will not receive the second signal.

    However as you point out there are many ways to skin the cat. The above is my personal favorite but is also the largest pack-space (though it's still pretty darn small) but it's also the most expensive.

    You can do it with a standard wakeup cable (or modify such a cable on your own with Radio Shack materials). All the system needs to work is to separate the back/body communication then
    - close the circuit briefly for wakeup
    - open the circuit
    - close the circuit again for the duration of the exposure (must be done within 5 seconds of wakeup)
    - open the circuit to end the exposure (shutter must be closed when exposure ends)
    If the above paragraph confuses/scares you then that's why you buy one of of the KG boxes through us - it makes it easy as cake.

    Doug Peterson (e-mail Me)
    __________________
    Head of Technical Services, Capture Integration
    Phase One, Leaf, Cambo, Canon, Apple, Profoto, Eizo & More
    National: 877.217.9870 *| *Cell: 740.707.2183
    Newsletter: Read Latest or Sign Up
    RSS Feed: Subscribe
    Buy Capture One at 10% off
    Personal Work

  10. #10
    Senior Member
    Join Date
    Feb 2009
    Location
    Scottsdale, AZ
    Posts
    484
    Post Thanks / Like

    Re: Contax / P1 users: What is the preferred workaround for long exposures?

    Thanks for the input! While I know which end of the soldering iron to hold, for the amount of money involved, I'd rather buy something off the shelf than roll my own. YGM accordingly...

  11. #11
    Senior Member
    Join Date
    Feb 2009
    Location
    Scottsdale, AZ
    Posts
    484
    Post Thanks / Like

    Re: Contax / P1 users: What is the preferred workaround for long exposures?

    Update: I bought the Kapture Group box from Capture Integration and so far, so good. It took me about 15 minutes to get the routine sequence down -- wake back, start exposure, open shutter, close shutter, stop exposure -- but otherwise, the process goes smoothly. :-)

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •