Anyone who has a Mamiya RB 150mm SF lens, can you confirm this for me?

Discussion in 'Medium Format Cameras and Accessories' started by tkamiya, Feb 19, 2013.

  1. tkamiya

    tkamiya Member

    Messages:
    4,252
    Joined:
    Oct 3, 2009
    Location:
    Central Flor
    Shooter:
    Multi Format
    This question concerns my newly acquired Mamiya RB 150mm C Soft Focus lens. This is the lens that comes with 3 disks.

    On this lens, there is a lever to close the aperture to the set value. On all other Mamiya lens, this lever goes to the end and when I let it go, it springs back. On this particular lens, as I move the lever, there is a definite friction point toward the end, and if I go further, it sort of "clicks" and stays there. I am guessing this "hold" feature is implemented to facilitate focusing, as this lens needs to be focused with aperture closed to around f/8. Can someone confirm this is the case? (or your lens does the same thing?)

    Thank you.
     
  2. akaa

    akaa Subscriber

    Messages:
    223
    Joined:
    Jan 29, 2010
    Location:
    Sacramento,
    Shooter:
    35mm
    your "guess" is correct
     
  3. tkamiya

    tkamiya Member

    Messages:
    4,252
    Joined:
    Oct 3, 2009
    Location:
    Central Flor
    Shooter:
    Multi Format
    Thank YOU!
     
  4. paul ron

    paul ron Member

    Messages:
    1,882
    Joined:
    Jan 22, 2004
    Location:
    NYC
    Shooter:
    Medium Format
    That is correct.. the preview locks at the end of it's travel to allow you to focus.
     
  5. akaa

    akaa Subscriber

    Messages:
    223
    Joined:
    Jan 29, 2010
    Location:
    Sacramento,
    Shooter:
    35mm
    Glad I could contribute something. Let me know what you think of the lens. I haven't really experimented much with it as a SF lens.
     
  6. tkamiya

    tkamiya Member

    Messages:
    4,252
    Joined:
    Oct 3, 2009
    Location:
    Central Flor
    Shooter:
    Multi Format
    I plan to play around with it soon. My first step is to have my girlfriend model for me, holding a resolution chart and try without the disk, from f/4 to about f/8, then wide open with the disks.

    Thanks both for your help!