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06-09-2013, 11:44 AM   #1
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Cosina 28-70mm f4 Macro

Ever seen one?
Got it with a Ricoh XR-P, and 2 flashes for $16 including shipping from an eBay seller.
Couldn't find anything about it on PF, or anywhere else.

The large focus ring is fairly stiff, and the twist zoom has a problem.
If at infinity, the zoom ring will only turn about half way, i.e. if at 28mm it will only go up to about 50mm, and vice versa.
But if you back off infinity a ways, it will turn fully both ways, and can then be focused.
A bit fiddly, but usable.
Edit, the zoom ring has freed up, and the focus ring is better now. I'm happy!

Macro is 1:3.2.




first grab shots with the K-01.
at f/4


f/9.5 1600 ISO


f/9.5 800 ISO


f/8 800 ISO



Last edited by robtcorl; 06-09-2013 at 12:14 PM.
06-09-2013, 01:28 PM   #2
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Looks pretty good for a "movie ticket"-cheap lens! Quite a catch.
06-09-2013, 04:33 PM   #3
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QuoteOriginally posted by robtcorl Quote
Ever seen one?
Got it with a Ricoh XR-P, and 2 flashes for $16 including shipping from an eBay seller.
Couldn't find anything about it on PF, or anywhere else.

The large focus ring is fairly stiff, and the twist zoom has a problem.
If at infinity, the zoom ring will only turn about half way, i.e. if at 28mm it will only go up to about 50mm, and vice versa.
But if you back off infinity a ways, it will turn fully both ways, and can then be focused.
A bit fiddly, but usable.
Edit, the zoom ring has freed up, and the focus ring is better now. I'm happy!

Macro is 1:3.2.




first grab shots with the K-01.
at f/4


f/9.5 1600 ISO


f/9.5 800 ISO


f/8 800 ISO
Hi Bob,

I have one very similar to yours. I got it a couple weeks ago for about $20. Mine's a 35-70mm f/3.5-4.8, however it wouldn't mount on my K-01 until I extracted the "Ricoh pin". Did you need to do the same to yours?
06-09-2013, 06:49 PM   #4
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QuoteOriginally posted by Achromatter Quote
Hi Bob,

I have one very similar to yours. I got it a couple weeks ago for about $20. Mine's a 35-70mm f/3.5-4.8, however it wouldn't mount on my K-01 until I extracted the "Ricoh pin". Did you need to do the same to yours?
My lens was on a Ricoh camera, but it's a PK-A, so no pin to remove.

06-10-2013, 04:03 AM   #5
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You're lucky, a previous owner must have removed it already. In your pictures of it, it's clearly marked PK-A/R just like mine, and since you say it came off a Ricoh camera............

Once I got the pin removed, it went on smoothly, the few shots I took, at various focal lengths, all looked quite sharp to me. Good luck with yours, I think yours is a better focal range.
06-10-2013, 05:57 AM   #6
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QuoteOriginally posted by Achromatter Quote
You're lucky, a previous owner must have removed it already. In your pictures of it, it's clearly marked PK-A/R just like mine, and since you say it came off a Ricoh camera............

Once I got the pin removed, it went on smoothly, the few shots I took, at various focal lengths, all looked quite sharp to me. Good luck with yours, I think yours is a better focal range.
Wow, Thanks! I totally missed noticing the R, and didn't even look for a pin.
Just checked, and it does still have the pin, but it's smaller in diameter than the one I removed from a JC Penny's lens, rounded, and seems to be located slightly in a different area.

I've had it on and off the camera a few times with no problems, so I guess I'll leave it alone.
This one seems to be pretty darn sharp too, with good colors.
06-10-2013, 06:42 AM   #7
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Yes, it's a very small diameter. I have other lenses where there is a much larger diameter pin/contact in the vicinity of where the pin is on this one. Those have never caused any issues with mounting/un-mounting. But this one wouldn't mount at all. I tried setting it to the "A" position, then out of the "A" position, and no dice wouldn't mount.

I've had one lens not want to come off of one of my cameras once, and had to do the "feeler-gauge procedure" to remove it. That one was relieved of it's pin shortly afterwards.
06-10-2013, 06:48 AM   #8
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I have an old, dead SF1 that I usually try them on first, and had one that needed the, in my case, "razor blade procedure"

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