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12-31-2013, 05:52 PM   #1
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Kalimar 28-85 f/3.5 - Aperture Setting Discrepancy

OK, so I bought this lens off Ebay. I have a compulsion, but LBA aside, I was attracted to this lens because of the constant aperture and the focal range. As far as I have figured, Kalimar is some generic rebrand of Sears and the like.

The lens is... fine, works fine, has its quirks, but that's not the issue.

The issue is: The lens has an auto-aperture setting and my camera recognizes that the lens will dial down to f/1.7?, while the physical aperture ring will only allow me to open it up to f/3.5...

Physically, I don't think this is even possible for this lens to open up to f/1.7, right?

But, I set the aperture using the wheel to 1.7, 1.8, 2.0, 2.2, 2.5, 2.8, 3.2 and finally 3.5 (and all the way to f/22). On the AV setting, the camera does compensate the shutter speed accordingly and the images that I tested out in Manual mode with a shutter speed set at a constant 1/100s and ISO 400 reflected the changing aperture in the exposure of the image...

What in the world do I have here?

12-31-2013, 06:00 PM   #2
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I take it is a Ka mount with electrical contacts and an "A" setting? A photo of the rear mount of the lens might help or at least a chart of the electrical contacts and caps.

Contact pattern for f1.7 to 22
101*11
for f3.5 to 22
001*11

http://kmp.bdimitrov.de/technology/K-mount/Ka.html
12-31-2013, 06:35 PM   #3
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https://lh5.googleusercontent.com/-ehnNesGTfw0/UsNvhq81i2I/AAAAAAAAFH4/Hb3wN...231_192913.jpg

https://lh4.googleusercontent.com/-ucRJdnsPGe0/UsNvQQmKPpI/AAAAAAAAFHg/oHThy...25280%2529.jpg

Not sure if the links will work... Apologies in advance for the crappy cell phone pics. Will edit if links don't work.
12-31-2013, 06:45 PM   #4
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Interesting. Have you tried taking photos with the lens in A mode set to f/1.7 and then using the aperture ring set to f/3.5, and also using another lens set to f/3.5? That should clear up whether the lens truly has f/1.7 or just a buggy A mode. My money's on the later.

12-31-2013, 07:11 PM   #5
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As far as I can make out the contacts are configured correctly for f3.5 - 22. I notice it also has a "Ricoh" pin but it is a rounded contact so it shouldn't give you problems. All I can think of is the pins are not aligning true. Perhaps the contacts/insulators on the lens mount are on the outer bounds of the specification tolerances. Maybe cleaning the contacts/insulators on the lens and jiggling it a bit on the mount might get it set properly.
12-31-2013, 10:42 PM   #6
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QuoteOriginally posted by wahid_satu Quote
Interesting. Have you tried taking photos with the lens in A mode set to f/1.7 and then using the aperture ring set to f/3.5, and also using another lens set to f/3.5? That should clear up whether the lens truly has f/1.7 or just a buggy A mode. My money's on the later.
I will be giving a variety of these scenarios a try tomorrow. For tonight: Happy New Year! :-)
01-01-2014, 09:53 AM   #7
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Nothing to see here...

I took the lens off last night and gave the contacts a little burnishing with a microfiber cloth. When I reattached the lens it read the maximum aperture "correctly" at f/3.5... I've taken the lens off and on a couple times, but can't recreate whatever specific sort of situation caused it to misread in the first place.

I wouldn't exactly say, "mystery solved", but at least I don't have to puzzle over lens versus camera setting discrepancies...

It's a pretty nice lens, anyway. No creep, buttery smooth focus, quite sharp, but with a haze defect that gives that dreamy/glowy look that is not unpleasant.

Guess I'll keep it!

Happy New Year!

Last edited by severalsnakes; 01-01-2014 at 09:56 AM. Reason: typo
01-01-2014, 02:35 PM   #8
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Ah, one of those head scratchers. Go out and take lots of photos and share with us.

It may never happen again - perhaps something conductive was on one of the pins. If it does "fail" again count on it happening at the worst possible time

Happy photographing!

01-03-2014, 08:16 PM   #9
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I'm done with all this head-scratching!

The lens promptly went back to giving me "false" aperture readings when the auto mode was engaged (but still representational using the ring manually). My conclusion: It WAS the Ricoh pin causing the issue. Near as I can figure, it must've been causing some sort of short/illegitimate connection. I've removed the pin (with my husband's help!) and I have no more issues to speak of (because it was rather fussy about attaching and detaching). Tra la la!

It's a small victory, but I should probably open up that leftover bottle of cheap bubbly in celebration...

Edit: Well, I'm drinking the champagne, but the lens is once again showing me that it can open up to 1.7 when it's set to Auto. I give up. This post has officially taught everyone absolutely nothing.

Last edited by severalsnakes; 01-03-2014 at 09:41 PM. Reason: Admitting defeat.
01-05-2014, 12:46 PM   #10
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The horse might be dead, but I am still pretty energized about it.

After further attempts at understanding this beast I have come to a conclusion. I don't know the cause of the anomaly, but what is happening is:

The camera is referring to the apertures improperly. When the camera tells me that the aperture is 1.7, the aperture IS wide open, but only as open as the lens allows, that is, f/3.5.

I discovered this when I set the aperture, physically, to 8.0 and took a test shot of a house plant. Then I engaged the auto-aperture and set the aperture electronically to 8.0. The resulting image was EXTREMELY underexposed. After another series of test shots, a set using the physical aperture ring and a set using the electronic aperture settings in-camera, I have made my conclusion, and came up with a superficial chart and I'm pretty confident about understanding the miscommunication.

When the camera tells me the aperture is f/___, it's ACTUALLY f/___.

1.7 = 3.5
1.8 = 4.0
2.0 = 4.5
2.2 = 5.0
2.5 = 5.6
2.8 = 6.3
3.2 = 7.1
3.5 = 8.0
4.0 = 9.0
4.5 = 10.0
5.0 = 11.0
5.6 = 13.0
6.3 = 14.0
7.1 = 16.0
8.0 = 18.0
9.0 = 20.0
10.0 = 22.0

The camera, electronically, will let me keep adjusting the aperture (with the click wheel) from what it tells me is 10.0 all the way down to 22.0, but, obviously, the aperture blades aren't closing any more than they do when physically set to 22.0, so from what the camera tells me is f/10 all the way down to f/22, those images display the exact same exposure.

I have done a couple of test using the Green Button in manual mode with the auto-aperture engaged, and then also using the equivalent physical aperture setting, and the chart above appears to be accurate.

So, my conclusion is to just treat this lens like any of my other manual lenses, ignore the fact that it has an auto-aperture feature, and finally move on with my life. ;-) Unfortunately, a have a number of pictures that are going to have some really wacky EXIF data...

Last edited by severalsnakes; 01-05-2014 at 12:51 PM.
01-05-2014, 12:51 PM   #11
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The contacts aren't conducting properly, simple as that. It happens with some lenses. When it does, it can come and go and with the temperature as the metal expands/contracts, or the whims of the gods. I very much doubt the Ricoh pin had anything to do with it, however. Easiest fix is foil tape in the proper locations (where the conductors are that aren't working)...
01-05-2014, 01:22 PM   #12
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QuoteOriginally posted by vonBaloney Quote
The contacts aren't conducting properly, simple as that. It happens with some lenses. When it does, it can come and go and with the temperature as the metal expands/contracts, or the whims of the gods. I very much doubt the Ricoh pin had anything to do with it, however. Easiest fix is foil tape in the proper locations (where the conductors are that aren't working)...
I think you're absolutely right! Whims of the gods, indeed! I only thought the pin might have been the culprit because after removing it, the camera did read "properly" for a while. I now realize my mistake.

However, I needed to remove the pin anyway, because I ALMOST got the lens stuck on my ZX-L film body. Whoooops!

It is still a nice lens and I like it very much. Plenty sharp, still a pleasure to use, even with the fiddly aperture settings.

Some playtime pictures with the Kalimar from yesterday:



01-05-2014, 01:38 PM   #13
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All those ball bearings in the mount make me think it is a Kiron/Kino-made lens. My Kino 105mm macro did the same thing -- something about those conductors. (No amount of cleaning helped) I executed a more elaborate solution than tape (which involved removing the mount) because I was selling the lens and I wanted it to look pretty. Actually, the first thing you might want to try is to physically scratch up the conductors on the lens just a bit (i.e. scrape the top surface off to expose some new bare metal with another piece of metal -- sharp key or screwdriver works). Might fix it (tape thickens the mount so it is harder to take on/off). The only thing required of those areas is that they conduct, that's it. Maybe some sort of oxidation over time ruins the exposed surface...
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