a few k-mount questions....

glasbak · 09-08-2012, 12:40 AM

Originally posted by Tanzer

Are you saying that the K-1000 cannot meter correctly?

The film body K-1000 can meter correctly with K/M lenses.
My K10D not (depends a little on the lens max aperture), even with stopdown metering.

**Lowell Goudge** · 09-08-2012, 05:11 AM

Originally posted by glasbak

The film body K-1000 can meter correctly with K/M lenses.
My K10D not (depends a little on the lens max aperture), even with stopdown metering.

The metering issues with the K10D have been well documented. Do a search and you will find a graph which I have developed that fully shows the issue. It is largely related to the focusing screeni used

glasbak · 09-08-2012, 06:42 AM

Originally posted by Lowell Goudge

The metering issues with the K10D have been well documented.

Documenting a problem does not solve the problem, swapping the screen, swaps also the problem, the K/M lenses may meter better, but the A (and newer lenses) metering gets worse.

**Lowell Goudge** · 09-08-2012, 07:08 AM

Originally posted by glasbak

Documenting a problem does not solve the problem, swapping the screen, swaps also the problem, the K/M lenses may meter better, but the A (and newer lenses) metering gets worse.

define woirse.

there are two different issues.

with the stock screen, K mount lenses have a highly variable metering with aperture. but with the *ist D screen it is almost linear, tending from perfect for apertures around F2.8-4 and drifting slightly upward to +1 stop at F22.

with A and later lenses, each lens when using the stock screen has an error, which is constant for all exposures and only a function of the maximum aperture.

so when switching screens, you need to know for each A lens, the EV comp required to correct the error.

note however most people don't switch often between legacy MF and newer AF lenses for example. especially now since the K10D and K20D have been replaced twice over by the K7 and K5.

I agree its not perfect, but.....

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09-08-2012, 12:40 AM	#46
glasbak Veteran Member Join Date: Apr 2009 Location: Netherlands Posts: 369	Originally posted by Tanzer Are you saying that the K-1000 cannot meter correctly? The film body K-1000 can meter correctly with K/M lenses. My K10D not (depends a little on the lens max aperture), even with stopdown metering.

09-08-2012, 05:11 AM	#47
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,367	Originally posted by glasbak The film body K-1000 can meter correctly with K/M lenses. My K10D not (depends a little on the lens max aperture), even with stopdown metering. The metering issues with the K10D have been well documented. Do a search and you will find a graph which I have developed that fully shows the issue. It is largely related to the focusing screeni used

09-08-2012, 06:42 AM	#48
glasbak Veteran Member Join Date: Apr 2009 Location: Netherlands Posts: 369	Originally posted by Lowell Goudge The metering issues with the K10D have been well documented. Documenting a problem does not solve the problem, swapping the screen, swaps also the problem, the K/M lenses may meter better, but the A (and newer lenses) metering gets worse.

09-08-2012, 07:08 AM	#49
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,367	Originally posted by glasbak Documenting a problem does not solve the problem, swapping the screen, swaps also the problem, the K/M lenses may meter better, but the A (and newer lenses) metering gets worse. define woirse. there are two different issues. with the stock screen, K mount lenses have a highly variable metering with aperture. but with the *ist D screen it is almost linear, tending from perfect for apertures around F2.8-4 and drifting slightly upward to +1 stop at F22. with A and later lenses, each lens when using the stock screen has an error, which is constant for all exposures and only a function of the maximum aperture. so when switching screens, you need to know for each A lens, the EV comp required to correct the error. note however most people don't switch often between legacy MF and newer AF lenses for example. especially now since the K10D and K20D have been replaced twice over by the K7 and K5. I agree its not perfect, but.....

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