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04-09-2009, 10:13 PM   #16
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QuoteOriginally posted by jibbonpoint Quote
This thread claims that the LL60 doesn't work.

https://www.pentaxforums.com/forums/pentax-dslr-discussion/1157-katz-eye-ll60...work-k10d.html

I've a split screen in my K10D. It (so far) always agrees with the focus confirmation with manual lenses.
Thanks for the heads up. I probably will try the LL60 anyway. I have neither of the two lenses that gave you problems, and have two M lenses that are a bit awkward to use because I cannot just meter at any old f/stop and expect accuracy.

04-12-2009, 10:27 AM   #17
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QuoteOriginally posted by dlacouture Quote
Hello!

Well, you've found out the infamous bad exposure problem with manual lenses...
It's linked to the focus screen (before someone asks, the meter cell is located just above the viewfinder, that's why metering is dependent on the focus screen).

The original focus screen is designed to work with f/3.5-5.6 lenses, and to improve brightness with fast lenses.
Unfortunately, this makes it really unfriendly to manual lenses, as the increased brightness will fool the meter and underexpose below f/4, and will again fool the meter and overexpose above f/5.6...
I've found that underexposure can go as bad as -1.5ev, and overexposure +2ev...

To lessen this behavior, you'll have to change your focus screen for a LL60 or Li60 (made for the *ist line, but perfectly compatible with the k10/k20).
Worst variation will then be in a -1/2ev +1/2ev range...
How can I get those screens?
04-13-2009, 09:46 AM   #18
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QuoteOriginally posted by res3567 Quote
How can I get those screens?
I assume you're referring to the LL-60 or LI-60 screens.

They are becoming rare.

There is a seller on eBay. IIRC, the price of the screens is $39. But he ships from Japan so the shipping cost is something like $15.

B&H has better price/shipping charge but keeps saying "out of stock." But you may want to try placing an order. You never know.... B&H doesn't charge until they ship, and you can cancel the order before shipping.
04-13-2009, 10:21 PM   #19
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QuoteOriginally posted by SOldBear Quote
I assume you're referring to the LL-60 or LI-60 screens.

They are becoming rare.

There is a seller on eBay. IIRC, the price of the screens is $39. But he ships from Japan so the shipping cost is something like $15.

B&H has better price/shipping charge but keeps saying "out of stock." But you may want to try placing an order. You never know.... B&H doesn't charge until they ship, and you can cancel the order before shipping.
Thanks Man!

That was what I referring to.

04-14-2009, 04:16 AM   #20
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QuoteOriginally posted by jibbonpoint Quote
This thread claims that the LL60 doesn't work.

https://www.pentaxforums.com/forums/pentax-dslr-discussion/1157-katz-eye-ll60...work-k10d.html

I've a split screen in my K10D. It (so far) always agrees with the focus confirmation with manual lenses.
I have exchanged the K10 screen against the LL-60 more than a year ago and can only emphasize, that the manual metering got much better. And I cannot see anything getting worse with current lenses. So in my personal opinion, the LL-60 (or any other of these "old" screens) are a worthy investment.

Ben
04-14-2009, 04:33 AM   #21
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As far as exposure is concerned with manual lenses, the problems seems more likely to be due to the linearity of the diaphragm mechanism, which is not the same with the old vs. new lenses. The old lenses have a non linear diaphragm mechanism, and the new lenses is more (if not completely) linear.
04-14-2009, 06:41 AM   #22
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QuoteOriginally posted by flyer Quote
As far as exposure is concerned with manual lenses, the problems seems more likely to be due to the linearity of the diaphragm mechanism, which is not the same with the old vs. new lenses. The old lenses have a non linear diaphragm mechanism, and the new lenses is more (if not completely) linear.
When you hit the green button to meter with manual lenses, the camera stops down the aperture. It doesn't know what aperture the lens is set to, let alone whether the lens is linear.
04-14-2009, 08:35 AM   #23
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QuoteOriginally posted by flyer Quote
As far as exposure is concerned with manual lenses, the problems seems more likely to be due to the linearity of the diaphragm mechanism, which is not the same with the old vs. new lenses. The old lenses have a non linear diaphragm mechanism, and the new lenses is more (if not completely) linear.
I did tests and the diaphragm stops down perfectly mechanically. I used Sunny 16 with the M400/5.6, and it tracked perfectly across the f/stops. You can see them on my Flickr site. What does go wrong is the metering. There are two stops I can use on the 400 - f/8 and f/11. Either side of them, the metering is off. My current methodology is to use f/8 and interpolate from there to get what I need.

04-14-2009, 08:52 AM   #24
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QuoteOriginally posted by flyer Quote
As far as exposure is concerned with manual lenses, the problems seems more likely to be due to the linearity of the diaphragm mechanism, which is not the same with the old vs. new lenses. The old lenses have a non linear diaphragm mechanism, and the new lenses is more (if not completely) linear.
No. It is the focus screen that causes the problems. Switch out the stock screen for a DS screen or one of the others mentioned in this thread and you have perfect metering with the old "K" and M lenses.
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