Cosmicar/Pentax 25mm 1.4 sensor coverage

Discussion in 'Adapted Lenses' started by daniduke, Aug 11, 2015.

  1. daniduke

    daniduke New to Mu-43

    2
    Aug 11, 2015
    Dear fellow photographers,

    Long story short: Is there a version of the Cosmicar/Pentax 25mm 1.4 that doesn't cover the m4/3 sensor?

    Detailed version: I've done my research, and the result is that the above mentioned lens is what I need, but It seems to be rather rare in my country. Afterall, I managed to find one with a decent price, but I'm not sure this is the one I want. The seller states It's a 'C-mount Pentax/Cosmicar 25mm 1.4 (C2514-M) lens'. I googled C2514-M and according to some websites It is a lens designed to cover 2/3" sensors. My firts doubt is that I've never seen mentioned this lens not to be designed for 1" sensors. The second is that as far as I know these x/y" sizes on the internet mostly are not reliable facts. I mean ,I've met with the well known Fujijan 25mm 1.4 lens to be considered as a 1", 2/3" and even 1/2" lens although it certainly covers m4/3 sensor. Not to mention that the Feihua 25mm 1.4 are for 2/3" sensor and it too covers m4/3.

    I understand that you cannot give me a certain answer due to the lack of information about the lens, but please tell me It's what I think it is. :)
     
  2. barry13

    barry13 Super Moderator; Photon Wrangler

    Mar 7, 2014
    Southern California
    Barry
    Hi & Welcome,

    See
    http://www.ricoh-imaging.co.jp/english/products/catalog/pdf/2012_PENTAX_MV_eng.pdf
    and
    http://www.pentaxforums.com/forums/136-pentax-q/173752-new-c-mount-lenses-pentax-q.html

    The -M is rated for 2mp (megapixel) security cameras, and the -5M for 5mp.
    Both are listed as 2/3" format, whereas some other lenses in that catalog are listed as 25mm (1") or even 45mm.

    There's also a vignetting rating of 48%, but I don't know what sensor that is measured on, or what it is in comparison to.

    I wouldn't spend a lot of money on such a thing unless you can try it first or return it if necessary.

    There are lots of other good lenses out there, some are very affordable.

    Barry
     
  3. daniduke

    daniduke New to Mu-43

    2
    Aug 11, 2015
    Thank you Berry, this is some useful information.
    Afterall I gave up on buying this lens, mainly thanks to your reply and some other infos I found in the meantime. I found this video , my only source of sample photos taken with this lens. Although the coverage is far from being good enough, I think it can easily be enough for some. But not for me, I prefer full coverage.
    Nevermind, I'll go with the Pentax 110 24mm 2.8 then.
    Thank's again :)