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06-12-2012, 03:27 PM   #1
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Does this Kiron look right

Photos from my Kiron 28/2:







f/2, 5.6. and 11, respectively.

At first glance it looks like one of the elements is reversed. However, I found another fellow on the interwebs with similar results (can't find the link). Judging by the praise this lens receives, these results seem pretty bad...

Most descriptions list this lens as having 8 elements, however mine is definitely 7 and slightly different from diagrams showing 8.

Any suggestions?

06-12-2012, 03:36 PM   #2
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Did you just walk outside of your house and take the pics? If yes, was your house well air conditioned? If yes, was it warm/muggy/sticky feeling outside? If yes, next time wait for the lens to warm and wipe the condensation off of it. If no to any of those, then this is not normal and the lens seems to be botched...
06-12-2012, 03:37 PM   #3
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The first two are quite too soft. My Vivitar-Komine 28/2 and Vivitar-Kiron 28/2.5 are nothing like that. I've heard of the Kiron 28/2 being susceptible to sticky iris blades, but not this kind of icky softness. Maybe an element *is* reversed.
06-12-2012, 03:47 PM   #4
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Thanks for the replies. It's a new (old) lens and unfortunately, it was the same inside before I went out. Inside has been steady at around 43% humidity for the last week. I went out to check infinity.

If anyone has a diagram for the 7-element version of this lens, please share it and I will walk the insides.

06-12-2012, 03:51 PM   #5
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No, that does not look right. My Kiron 28 is a rock solid performer.
06-12-2012, 04:41 PM   #6
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Fixed

Fixed. One of the concave elements was flipped. Won't tell anyone what I paid for it...

Comparison @ f/5.6:





Seems to be fairly sharp at f/2 (not pictured). I'm excited to take it out. For now, infinity is way off...

Thanks for the second, third, fourth set of eyes!
06-12-2012, 04:58 PM   #7
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Hey, I think you are on to something there. Maybe's that's a Kiron made lensbaby!
06-12-2012, 05:11 PM   #8
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Haha, the thought occurred to me!

*insert quip about glass vs plastic*

06-12-2012, 07:15 PM   #9
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QuoteOriginally posted by BradleyS Quote
For now, infinity is way off...
What's that about? My Kiron 28mm f/2 is sharp and has no issue with infinity focus.







Looking at the last photo, it doesn't look very sharp. IIRC it was twilight when I shot that, but maybe I should check infinity again.

Last edited by audiobomber; 06-12-2012 at 07:23 PM.
06-12-2012, 08:06 PM   #10
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Nice photos. It's not surprising that infinity was off on my copy, given that it had other issues. Not a lens-specific problem, just my copy that was off. I fixed that too. Good as new!

Once I got her locked in I immediately thought, "now that's what I've been hearing about!" Very nice lens.
06-12-2012, 09:27 PM   #11
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QuoteOriginally posted by BradleyS Quote
Nice photos. It's not surprising that infinity was off on my copy, given that it had other issues. Not a lens-specific problem, just my copy that was off. I fixed that too. Good as new!

Once I got her locked in I immediately thought, "now that's what I've been hearing about!" Very nice lens.
Good to hear!

Have you checked out the crazy bokeh at f/2?

06-12-2012, 09:57 PM   #12
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I somewhat prefer the reversed element for the radial distortion, but it's much more versatile assembled as designed. Nice find!
06-12-2012, 10:21 PM   #13
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Hmmm, I wonder how hard it would be to dissect one of my extra M50/2's and reverse an element to get such atmospheric effects?
06-13-2012, 04:52 AM   #14
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QuoteOriginally posted by icywindow Quote
I somewhat prefer the reversed element for the radial distortion, but it's much more versatile assembled as designed. Nice find!
QuoteOriginally posted by RioRico Quote
Hmmm, I wonder how hard it would be to dissect one of my extra M50/2's and reverse an element to get such atmospheric effects?
I'd rather have a properly functioning Kiron. The Sears 135mm f2.8 macro has this look at wide apertures in macro mode, but range is limited to a few meters.



06-13-2012, 06:22 AM   #15
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QuoteOriginally posted by RioRico Quote
Hmmm, I wonder how hard it would be to dissect one of my extra M50/2's and reverse an element to get such atmospheric effects?
I'm guessing you wouldn't get the same result easily with a normal prime. The convex element to the rear of the Kiron is seriously curved!

–––––
| .__. |
|/ .... \|

With an element that deeply convex flipped around, it's no wonder why it was so crazy. I dare say that at f/5.6 the center 10-20% of the frame was sharp enough to be usable as an effect lens. The only truly ugly symptom at that aperture is somewhat high CA toward the edges, but I guess that should be expected.

I wouldn't mind trying this with an inexpensive off-brand wide angle.
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