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Pentax P50 K-Mount?

  • 15-09-2009 6:33pm
    #1
    Miguel_Sanchez
    Closed Accounts Posts: 8,417 ✭✭✭


    I'm going to buy a new lens for my old Pentax P50 and I just wanted to double check with folks here that would know more than me that the lens mount on a P50 is a K mount.

    Obviously I don't want to buy a lens and find it doesn't fit.

    So the following statement is true or false?

    The Pentax P50 film camera will take any lens that is specified as K Mount.


Comments

  • #2
    AnCatDubh
    Registered Users, Registered Users 2 Posts: 6,393 ✭✭✭AnCatDubh


    Sure is.

    A KA to be precise. If you are stuck for a manual try here

    Wikipedia
    KA mount
    The KA mount is derived from the original K mount. It allows the lens' aperture to be set by the body, and thus permits shutter priority and program auto exposure modes. It was introduced in 1983, and is supported by A-series and P-series bodies; Pentax lenses that support it are marked 'SMC Pentax-A'. It is completely backward-compatible with the original K mount.
    The aperture on the lens is set from the body by the same stop-down lever found on the original K mount, but on KA lenses this lever is proportional to the area of the aperture opening, rather than the diameter as on previous lenses. This allows the body to easily set a specific aperture, since the relationship to F stops is linear. The lenses add an 'A' setting on the aperture dial, which gives the body control of the aperture. Other, numeric settings are used for manual aperture modes—aperture priority and full manual mode.
    Six electrical contacts are added to the bayonet ring. One is slightly recessed and allows the lens to indicate whether the aperture ring is set at 'A' or not. If it is, a pin on the lens extends slightly and makes contact, while if the lens is at any other setting the pin is retracted and does not make contact. The other five contacts are used to encode the lens' aperture range. Each contact on the lens is either conducting or non-conducting, providing a binary 1 or 0, respectively. Two contacts encode the lens' minimum aperture—f/16, f/22, f/32 or f/45; although no Pentax K-mount lens has ever had an f/16 minimum aperture, OEM lenses often have. The other three contacts encode the lens' maximum aperture; their meaning is dependent on the minimum aperture indicated by the lens.

    Have fun with it.


  • #3
    Miguel_Sanchez
    Closed Accounts Posts: 8,417 ✭✭✭Miguel_Sanchez


    Thanks a million.

    Now to find me a nice long lens.


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