Lenses with abberations that are useful.

Discussion in 'Pentax' started by jim kerr, Oct 13, 2009.

  1. The one I have is a Focal ( K-Mart) 35mm f2.8 Preset that gives a certain glow to shinny things, caused by some abberation defect, I suppose. I guess there are reasons to have cheap lenses!........Jim
     
  2. If you're comfortable with tools, try reversing the rear lens element. It leaves the center of the image more-or-less in focus but does strange things to the rest.
     
  3. Zane, do you have any examples of this? I've been fiddling with various lens components but not really getting anything that I am happy with or is versitile enough. Could I simply buy a kit lens (18-70 in my case) and find a way to reverse the rear element? I'm after that 'stretched-blurry' lensbaby-type-look. Thanks for your help!
     
  4. Get a $5 lens and crack the front element...you may be the next Picasso, :)
     
  5. Richard, this thread has a few shots from altered lenses. I took a cheap M42 28mm lens and reversed the rear element and got similar results. I'll try to dig up a shot or two and post later. I switched the rear element only because it was the easiest to get at, I'm sure swapping other elements or mixing elements from two lenses would "work" too.
     
  6. Thanks Zane. The final two shots on that thread are more or less what I'm after. I would be very happy with those infact. The thing that bothers me is aperture control, it's something I'd probably want to keep. This is why I'm inclined to buy a cheap kit lens (the Sony 18-70 in my case) and either reverse the rear element or replace something what the spares I have... that way I would maintain the aperture control... Worth a shot?
    I'd be interested in seeing any more samples you have if you have the time... Especially with the 28mm M42 lens, as I'm quite fond of that f/length on APS-C, although having 18mm would also be nice. Thanks for your help!
     
  7. Any update Zane?
     
  8. Working on it...should have some shots this week. The concept does work, so you have nothing to lose by trying. If you don't like the results you can always put the lens back in its original configuration.
     
  9. Okay, here we go. This M42 lens is marked "D/B CAMERAS 1:2.8 f=28mm" and takes a 49mm filter. It appears to have a lens coating. There's very little on the web, but it seems like they're sold as security camera lenses. The rear comes apart with only three screws, which made it easy to reverse the rear element. I'm not sure how many elements/groups it has.
    These were taken with a *ist DS with the M42-K adapter from Pentax. Stop down metering seems to work fine. Shooting at f/2.8 is dicey, strange things happen to bright round objects at the periphery. Things look more reasonable at f/8. YMMV.
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  10. The Big Corsair
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  11. Dogtags
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  12. Thanks so much for your help Zane! This is exactly the sort of 'control' I was looking for, wonderful! I'm going to go buy a cheap 28mm M42 now... Hope it works as well as yours does.
     
  13. Another abberated lens, from a russian Cyclop-M1 night vision device. This is a version with an M42 thread and protuding element way behind the mount - I simply put it off and now it's usable at infinity. Rest is here . This is an 85/1.2 lens and there is another version with less protusion. Both don't have an aperture though.
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    Above: A broke 3.5/35 Enna lens (most probably elements reverted or missing)
    I would guess you will get similar results with any lens by reverting elements or leaving them off.
    Best of success, Georg
     

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