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07-27-2010, 11:43 PM   #16
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QuoteOriginally posted by MPrince Quote
Just out of curiosity, what are the names and issue dates of these photo magazines you refer to?
i'll check and let you know the name of the magazine. definitely were the latest month's issues, but only one of them i brought with me back home.

I'll let you know the name when i go home..

The foreign magazines were 15-20$ and the Malaysian ones cost around 3-5$

07-28-2010, 01:14 AM   #17
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QuoteOriginally posted by Marc Sabatella Quote
There's nothing broken, hence nothing to fix. The camera exposes very well according to ISO standards. It makes no attempt to read minds, but it does provide exposure compensation control - like every other camera - so you can tell the camera ow you want the exposure to differ from standard.
Yes I do understand that you can tweak exposures. I have the the Canon A550 mentioned by Fekish, and it does indeed manage exposures in "normal' picture situations much better than the Kx!
07-28-2010, 04:38 AM   #18
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QuoteOriginally posted by MPrince Quote
I looked at image #10. ISO 200, Aperture priority, f4, 1/400 around 8:40 pm. I don't know what your latitude is, but I'd say it was near sunset. Call it an EV of 9 or 10. At that ev, shooting at f4 with an iso of 200, your shutter speed should be 1/60 (ev 9) or 1/125 (ev 10), so yes, the shot is underexposed.
True, except that many of these shots are taken on an overcast day, but into the sun. The camera is preserving the detail in the sky. I think that may actually be the best exposure for these shots.

Two nights ago, I was scanning a few old rolls of slides of Switzerland from 30 years ago, taken with an MX. I often let that kind of sky in my slides go white to make a bright slide on the building or mountain, but if I tried, using my best manual skills (such as they were) to preserve the sky, I got the same kind of "dark" shot.



FWIW, the above color balance and exposure is where Photoshop places it using "auto" settings, as well. I suspect that 30 years may have shifted the Agfachrome color a bit.

If I override the auto settings in Photoshop and brighten and warm up the foreground (without masking), I lose the sky:


Last edited by GeneV; 07-28-2010 at 05:17 AM. Reason: added example
07-28-2010, 10:00 AM   #19
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QuoteOriginally posted by marty-0750 Quote
Yes I do understand that you can tweak exposures. I have the the Canon A550 mentioned by Fekish, and it does indeed manage exposures in "normal' picture situations much better than the Kx!
Yes, some beginner level P&S cameras do attempt to attempt to "read minds" because they assume the photographer doesn't understand exposure well enough to make the necessary adjustments, and thus they perform some "auto adjustments" to attempt to produce pleasing pictures even though the results are not technically correct according to traditional photographic exposure standards (eg, those established by the International Organization for Standardization). You will find that DSLR's do not tend to do this - they tend to expose according to ISO standards, which do require use of compensation in well-defined situations.


Last edited by Marc Sabatella; 07-29-2010 at 11:55 AM.
07-28-2010, 10:32 PM   #20
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QuoteOriginally posted by Marc Sabatella Quote
Yes, some beginner level P&S cameras do attempt to attempt to 'read minds" because they assume the photographer doesn't understand exposure well enough to make the necessary adjustments, and thus they perform some "auto adjustments" to attempt to produce pleasing pictures even though the results are not technically correct according to traditional photographic exposure standards (eg, those established by the International Organization for Standardization). You will find that DSLR's do not tend to do this - they tend to expose according to ISO standards, which do require use of compensation in well-defined situations.
Ok then that seems to make sense. So it's like doing it the old way with film SLR's, like using the 16/125 rule, checking the viewfinder readings and tweaking manually. I checked my slide collection and found many under-exposures in outdoor landscapes similar to the K-x when using centre-weight metering before I knew how to compensate. By contrast evaluative metering does a better job of balancing the exposure for normal scenes. I prefer to use centre-weight as I know what it covers in the frame, but eveluative could be doing anything as it scans the distribution of luminoiusity over the frame to make its decisions - sometimes over exposing.

BTW Has anyone downloaded Pentax's firmware update into their K-x? Is it worth it?

Martin
07-29-2010, 03:50 AM   #21
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QuoteOriginally posted by marty-0750 Quote
BTW Has anyone downloaded Pentax's firmware update into their K-x? Is it worth it?

Martin
It's free. Why wouldn't it be worth it?
07-29-2010, 11:58 AM   #22
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QuoteOriginally posted by marty-0750 Quote
Ok then that seems to make sense. So it's like doing it the old way with film SLR's, like using the 16/125 rule, checking the viewfinder readings and tweaking manually.
Well, it's not *that* bad. All you really need to know if that when a scene is brighter than average, dial in positive compensation if you want it to *look* brighter than average, and when it's darker than average, dial in negative compensation if you want it to *look* darker than average.

QuoteQuote:
By contrast evaluative metering does a better job of balancing the exposure for normal scenes. I prefer to use centre-weight as I know what it covers in the frame, but eveluative could be doing anything as it scans the distribution of luminoiusity over the frame to make its decisions - sometimes over exposing.
I feel similarly - the matrix/pattern/evaluative metering could *potentially* figure a lot of stuff out, but it's much less harder to anticipate what it might do in a given situation. So it's hard to predict when compensation might be needed, and therefore I stick to good old center-weighted metering.
07-29-2010, 06:22 PM   #23
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QuoteOriginally posted by MPrince Quote
It's free. Why wouldn't it be worth it?
What I meant is it worth installing into the camera? I understand it's a bit risky if you stuff up the process it could result in a trip to the factory for a reset. And also by "worth it" I would be looking for enhancements such as illuminated red-focus-indicator (like in the K100D), and say, instant-access to user pre-set setups in the menu rather than have to run through repetitive button presses every time. Not interested in those "special effects" they seem to be offering in the current update.


Martin

07-29-2010, 08:41 PM   #24
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QuoteOriginally posted by Marc Sabatella Quote
Well, it's not *that* bad. All you really need to know if that when a scene is brighter than average, dial in positive compensation if you want it to *look* brighter than average, and when it's darker than average, dial in negative compensation if you want it to *look* darker than average.

I feel similarly - the matrix/pattern/evaluative metering could *potentially* figure a lot of stuff out, but it's much less harder to anticipate what it might do in a given situation. So it's hard to predict when compensation might be needed, and therefore I stick to good old centre-weighted metering.
Ok, I think I've nailed what's going on. It does appear light gets through the view finder and affects the meter reading. Especially in day light out in the open there is plenty opportunity for light to sneak in. This explains two things when using centre-weight metering:

1) exposures out in the open with a lot of light coming from all directions are consistently under exposed by 0.5 to 1.0 stop

2) when shooting under same outdoor conditions in live view exposures are more "correct" - why? because in live view the mirror flips up and entirely blocks light leaks from the viewfinder and prevents interference with the reading.

I road tested this with camera on tripod outdoors in the open and watched how the metering changed as I covered the view finder with my hand and then with live view on and off. Yep light gets in through the view finder alright and interferes with the reading. Also explains why many of my out-door-in-the-open slides from my Olympus OM1 are similarly under exposed.

So you need your wits about you when judging exposure with DSLR (& SLR).

Martin
07-30-2010, 08:50 AM   #25
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QuoteOriginally posted by marty-0750 Quote
Ok, I think I've nailed what's going on. It does appear light gets through the view finder and affects the meter reading.
Definitely when shooting on a tripod - that's why the camera comes with a viewfinder cap. Shouldn't be an issue in handheld shooting, though. I still don't understand enough abut how metering works with liveview, never having used a camera with that feature.
07-30-2010, 10:58 AM   #26
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QuoteOriginally posted by marty-0750 Quote
What I meant is it worth installing into the camera? I understand it's a bit risky if you stuff up the process it could result in a trip to the factory for a reset. And also by "worth it" I would be looking for enhancements such as illuminated red-focus-indicator (like in the K100D), and say, instant-access to user pre-set setups in the menu rather than have to run through repetitive button presses every time. Not interested in those "special effects" they seem to be offering in the current update.


Martin
It fixes some bugs and is definitely worth doing.
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