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10-29-2010, 05:46 AM   #16
Ira
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QuoteOriginally posted by MrA Quote
Interesting we're in some sort of agreement that something wierd is going on.

Am going to pick up some conductive tape, or maybe conductive paint (good idea?) from Maplins Electronics tonight.

Here's a question, though. How does the camera know it's got a lens mounted at all (rather than just a big gaping hole)? Is it possible the camera isn't picking up the presence of a lens for ... some reason? Presumably with K mount lens it's those contacts, but if the m42 lens doesn't (normally) interfere with them, then how in that case? I mean, what stops the camera trying to offer antishake when no lens is mounted if you take a shot?
That's what doesn't make any sense in your case:

If there's no lens on there, it will offer you the FL selection for SR. (I just tried it on my K-x, but granted, your camera is different.) It's not SUPPOSED to stop offering you SR, unless it's a modern auto lens, where it gives it to you automatically if you have it on by default.

Your camera IS picking up the presence of a lens, but something is shorting somewhere or not contacting...the firmware thinks it's an auto lens...and then corrects itself and gives you nothing.

Have you tried the scotch tape test yet? Also try powering up without a lens, and see if you get the same results I did.

10-29-2010, 07:38 AM   #17
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I would say shorten all the contacts and you'll be OK. Here is a table telling which contact combination does what.

My K100D does give the FL choice if I start it up without any lens.

Of all likewise problems I have had, it was always the camera contacts as the source of the problem. Last time I had a lens on which only touches the contacts with the edges (anodized lens). The camera was REALLY acting up, resetting and switching itself off frequently. Really scary if you did not know it was only for the contacts.

Mind you, there is also a big difference if the lens back is anodized (black) or blank metal.

I have gotten some 0.25mm masking foil. A cut out ring of it eliminates all those problems. Reaching inf. with it is a little more questionable though. On isolated lenses with enough width I put a strong aluminium foil (like from those printer cartridge bags) + very thin double sticky tape on. Consistent behaviour all of a sudden. BTW congrats on the lens, a real goodie.
All the best, Georg

Last edited by georgweb; 10-29-2010 at 07:44 AM.
10-29-2010, 08:11 AM   #18
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QuoteOriginally posted by georgweb Quote
My K100D does give the FL choice if I start it up without any lens.
This is the first thing I would try. If it behaves properly with no lens, then the issue would be with the lens. As Georg says, there is the off chance that the lens base is partially conductive and causing this issue. Rather than shorting all the contacts, it should be enough to simply insulate the "A" contact. If there is no continuity at that point the others are ignored.

This discussion is sort of talking around a key concept that is not being addressed. That being:
When a M42 lens is mounted, the camera should behave as if NO lens is mounted.


Steve
10-29-2010, 11:01 AM   #19
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Ok, home from work again now, and I *think* I've solved it. There's another obscure menu option.

QuoteOriginally posted by stevebrot Quote
When a M42 lens is mounted, the camera should behave as if NO lens is mounted.
My K100d was behaving differently to georgeweb's (2 posts up), in that when no lens was mounted, upon power on screen was displaying "aperture priority, auto exposure" and the no-antishake symbol. So it was being different but consistently so.

So I explored the menus again. And fiddled.

Under "custom settings" is an option "FI with S lens used", the expanded description is "when S mount lens used, focus indication funct is made available".

I turned it on. SR now works.

So now it's just a question of enabling trap focus. Re the shorting, just checked the lens, it's external diameter is small enough that it doesn't touch the contacts (hairs breadth of clear air between them), so it'll have to be tape not paint.

QuoteQuote:
BTW congrats on the lens, a real goodie.
Cheers, I'm hoping so. Need some decent weather to go test it now.

On the asumption it's resolved, thanks to all for the assistance. Many minds and all that.


Last edited by MrA; 10-29-2010 at 11:16 AM.
10-29-2010, 04:37 PM   #20
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Oy vey.

All of this for a menu setting.

But I'm going to print this thread in case I ever pick up the same body!!!
10-29-2010, 10:40 PM   #21
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QuoteOriginally posted by MrA Quote
Under "custom settings" is an option "FI with S lens used", the expanded description is "when S mount lens used, focus indication funct is made available".

I turned it on. SR now works.
Well, you learn something new every day and this one is definitely new!


Steve
05-20-2011, 10:48 AM   #22
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Are You got all answer? Are You K100DS with Jupiter Work propertly ?
I have fev Jupiters, and use sucsesfully on K100D, MZ-6, ME Super and K-x.
If any questions - ask...
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