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Weird problem with saka 135mm/2.5

Discussion in 'Adapted Lenses' started by xXx1, Feb 23, 2013.

  1. xXx1

    xXx1 TalkEmount All-Pro

    Jan 15, 2013
    I got about a month ago that lens. It is quite rare and mechanically in very fine condition. One of lenses had pretty bad fungus growth and there was quite much something greasy (helicoid lube?) on the same lens too. Cleaning was pretty difficult (dish soap+water > isopropyl alcohol>isopropyl alcohol&ultrasound cleaner>24 h soak in acetone) and one lens did lose some of multicoating in the process/fungus has eaten it. This is normal so far. I removed the 3 lenses from head and the back was as it was. I think that I put everything back correctly but the lens focuses like there would be a extension tube. That is, it focuses from something like 50 cm to one meter. Image quality isn't bad but not great:
    DSC01179_zps51474110.
    (this is 100% crop)

    The front lenses were 2 menisculus lenses and one double convex and they don't simply fit any other way in. As it is 135mm lens few millimeters don't have this kind of effect (extension tube of something like several cm might cause this).

    Any ideas?
     

    Attached Files:

  2. Bimjo

    Bimjo Super Moderator

    Oct 28, 2011
    Washington State
    Jim
    Is it possible that the double convex element is asymmetrical and you got it in backwards? That's really a stretch though I guess. :(
     
  3. xXx1

    xXx1 TalkEmount All-Pro

    Jan 15, 2013
    I will try to swap it. It is just so weird that there has to be some simple explanation.

    I really wouldn't bother with that lens but it is really rare and mechanically in fine shape. Maybe it has been broken from the start (something like missing element etc.).
     
  4. Bimjo

    Bimjo Super Moderator

    Oct 28, 2011
    Washington State
    Jim
    I wonder if this is one of those lenses that needs a small filter on the rear to function correctly (like a 500mm mirror or the Zenitar 16mm fisheye)?