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06-15-2012, 11:07 AM   #16
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I hope you are fully aware of how the lens will act with the aperture lever cut off - basically, like an M42 mount without the A/M switch and that constantly makes a sound when pressing the green button to meter. That, beside always having a dim viewfinder to focus with, when not set at f/2.
I suggest you make use of the optical preview option of your camera.

06-15-2012, 11:22 AM   #17
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That's something I didn't think of for the A-mode and actuation lever swap, actually. I'd be happy to use it in A-mode, but forgot about the darker viewfinder. This certainly complicates things.
06-15-2012, 11:43 AM   #18
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Of course it complicates things. Unfortunately, there are limitations that you have to live with, like this particular one. What you have discovered, and bothers you, is the "crippled" KAF mount, which all Pentax DSLRs and some later film SLRs share. These do not have the ability to continuously meter K and M series lenses, but older bodies like the MX, K1000 or ME super still can. Until Pentax comes with a (fictive) full-frame body with uncrippled mount, there is no other solution to the stop-down metering of old lenses. But believe me, the green button is the most practical solution given the current constraints. You can also try optical preview, as I stated earlier. It stops the lens down as long as you keep the button pressed, and it gives you a continuous EV bar in the viewfinder, like the one in the Olympus that you always mention. It's too slow to be practical, but I feel it's there for people like you to be happy.
06-15-2012, 04:35 PM   #19
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QuoteOriginally posted by snake Quote
..... Then I can just run it in Aperture priority. Simple.
It is a tempting option the purple fringing dies off really quickly with one stop down.
Hope you can do it without damage. Shame to munt a marvellous lens !
Pete

06-16-2012, 03:46 AM   #20
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QuoteOriginally posted by kcobain1992 Quote
Of course it complicates things. Unfortunately, there are limitations that you have to live with, like this particular one. What you have discovered, and bothers you, is the "crippled" KAF mount, which all Pentax DSLRs and some later film SLRs share. These do not have the ability to continuously meter K and M series lenses, but older bodies like the MX, K1000 or ME super still can. Until Pentax comes with a (fictive) full-frame body with uncrippled mount, there is no other solution to the stop-down metering of old lenses. But believe me, the green button is the most practical solution given the current constraints. You can also try optical preview, as I stated earlier. It stops the lens down as long as you keep the button pressed, and it gives you a continuous EV bar in the viewfinder, like the one in the Olympus that you always mention. It's too slow to be practical, but I feel it's there for people like you to be happy.
It's truly a disappointment. Sure, stop-down, green-button metering is actually nice, but it's not ideal in fast-changing conditions. However, if I shoot up to f5, I'll be ok, but it looks like unless I clean out the linkages from the actuator side of the mechanism, I won't be shooting in bright conditions with this really nice lens, a real bummer, actually. The thing is I'm worried about screwing up the aperture blades with oil if I try to free up the linkages. I was basically 1 level of disassembly above them. Sending it out to the above-suggested person is not an option, as I'm in Germany.
06-16-2012, 03:49 AM   #21
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QuoteOriginally posted by Transit Quote
It is a tempting option the purple fringing dies off really quickly with one stop down.
Hope you can do it without damage. Shame to munt a marvellous lens !
Pete
removal of the lever is achieved damage-free, via two screws for the mount and a couple of tiny washers. The lever itself is fastened with a screw, so using something else from a donor would work also damage free and still keep the two linkages and spring connected and takes all of ten minutes to do, start to finish.
06-16-2012, 08:41 AM   #22
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Progress was made. It only took a long time to reassemble properly because I didn't realize the focus ring could engage the threads several different ways. I finally indexed it with the top screw on the housing of the front lens group with 4/13 on the focus dial. At a later time, I'll tear in again because there's a fiber on the middle element that I want to get off and a screw fell through the aperture and left only a light trace, so I'll have to clean it. Thus far, I don't see any issue. Aesthetically annoying, however. The good thing is the lens is metering great up until at least f11. I couldn't access all the linkages, as the last piece appeared to be pinned, but I was able to get a small amount of lighter fluid in there with a q-tip and clean it repeatedly and work the linkage until it got faster and faster. I cleaned a good amount of the old grease out, added literally a film amount of grease and added micro-droplets of oil (if anyone knows about watchmaking, they will know what amount we're talking). So it appears to have worked, so thanks very much. Annoying about having to clean that middle element through the iris, but I have it working.
06-16-2012, 12:28 PM   #23
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Sorry to stack- I decided to tear into it again, since it was easy to remove the rear plate and rear element to clean the grease traces left by that screw and the fiber. Cleaned it all out, was done in 15 minutes flat. love this lens now. I'll determine if the blades are still slow, but I at least I have a better usability range and got some experience in taking one apart.

06-17-2012, 04:05 AM   #24
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Sounds like a success story , interesting read.

You stimulated me to get the 85/2 out to the farmers market
Pete

edit: removed shot of random hippy

Last edited by Transit; 06-17-2012 at 05:02 PM.
06-17-2012, 07:23 AM   #25
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I would say so. Enjoyable experience and I took it out today and shot with it. Very, very usable, most nice and sharp, very easy to use with CIF. Those shots will be up on my blog later today, among many, many others.

Thanks for the help!

Here are partially exploded views:



06-17-2012, 07:27 AM   #26
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Glad you did it after all.
06-17-2012, 08:09 AM   #27
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QuoteOriginally posted by kcobain1992 Quote
Glad you did it after all.
I didn't get to the last portion, which would reveal the blades and mechanism leading to them, but close enough, I hope. It appears that last portion is pinned in place and without knowledge or references, I was not going to do anything with it.

Also, it's nice that the rear element is screw-on, as one blade got a tiny bit of oil on it, so I was easily able to go in with a bit of solvent and get it off, as well as the blade coating that flaked off from somewhere and left a tiny piece in the middle.

Check the blog in my signature. I just posted some shots from a festival. From "Sunday afternoon", the first maybe half-dozen shots are with the m85.
06-17-2012, 03:35 PM   #28
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Braver man than me !
06-17-2012, 05:04 PM   #29
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QuoteOriginally posted by snake Quote
......... Very, very usable, most nice and sharp, very easy to use with CIF.
Certainly is !
have you tried it with trap focus at all?

Pete
06-17-2012, 09:13 PM   #30
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Interesting story, thanks to all participants.
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