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06-16-2008, 06:45 AM   #46
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QuoteOriginally posted by RiceHigh Quote
Well, please behave yourself and respect yourself at the first place, even you don't respect others.
Respect, in an acedemic sense, should be earned. It is not just a given.


QuoteOriginally posted by RiceHigh Quote
Not true. My test chart was created using all 128 RGB values and it was calibrated against a Konica Minolta incident light meter, which was calibrated in KM's laboratory and had a calibration certificate issued. For all others who are interested, read:-

I have used my test method to check for the exposure accuracy of my MZ-S and the EOS 300D - no problem - they all agreed in general with my chart and the expensive calibrated KM light meter. Most importantly, they *reproduced* the 128 values. So, it must be my Pentax DSLRs that were different, but not *all* others, even including a Pentax film SLR.
.
I've ran out of ways to show you that the value of a correctly calibrated meter, shooting a uniform target, should have a peak at 110 in RGB color space, gamma 2.2. I'm sorry you are just plain and simply wrong........ Try a Nikon or Olympus. Your use of "all others", like you tested EVERY LAST DSLR on the planet is MISLEADING at best.

In fact, when we look at the ISO standard for hand-held exposure meters, we find
that there is a substantial range of “calibrations” allowed, which can lead to a
considerable range of the ratio Hu/Hsat.

In an sRGB color space basis, for a chromaticity neutral (“gray”) scene), this
would correspond to RGB values of about 113,113,113.

HOW you can still deny this FACT is beyond me...
So, after we see the exposure1 that the metering system recommends
(or actually sets) when the meter is regarding the 18% gray card, we manually force the camera to use a 1/2 stop greater exposure1 and
use that for the shot.
Why are gray cards of 18% reflectance readily available, and those of
12.8% reflectance almost non-existent? The answer lies in decades of
evolution and folklore, and in part from the fact that things work
differently in the film world (in which the use of the 18% reflectance
card arose) than the digital world.
For one thing, film doesn’t really have a clear saturation value of
exposure2. Accordingly, the matter of a “cushion against
overexposure” is not so compelling.

http://doug.kerr.home.att.net/pumpkin/Exposure_metering_18.pdf
#
http://doug.kerr.home.att.net/pumpkin/Exposure_Calibration.pdf
QuoteOriginally posted by RiceHigh Quote

So, if you like the way that your Pentax DSLR (you still have a *ist D, right?) exposes, fine. I am not beating a dead horse but if people are starting new thread like this one and asking for info, I will surely to share my knowledge and experiences on this issue.
You are more than welcome to share your "opinion", just don't pawn them off as some undeniable facts, nor your "research" is anything more than" hypothesis w/ a VERY SMALL set of data, regardless how large you think it is..


QuoteOriginally posted by RiceHigh Quote
It is not important anyway, please first re-learn how to first respect yourself and then the others, my humble words.
No, since you are selling yourself, the question is valid. This is the internet, accepting your word on your credentials, especially when your methods contradict them, is just plain silly. sorry that you feel it is a bit rude.

06-16-2008, 06:53 AM   #47
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QuoteOriginally posted by RiceHigh Quote
I am not beating a dead horse but if people are starting new thread like this one and asking for info, I will surely to share my knowledge and experiences on this issue.
Actually Mr. RiceHigh, if you took the time to read threads in this forum from their beginnings (i.e. learning who the posters are and their history with the camera) rather than limiting your responses to only those topics to which you feel to be an expert, you might have realized that the original OP was brand new to the camera and was unfamiliar with it's operation. Everything you profess is purely academic, and in reality a whole pile of hooey. I have now owned my K10D for 7 months and find your responses to these threads pure rubbish.
06-16-2008, 07:05 AM   #48
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QuoteOriginally posted by jeffkrol Quote
Respect, in an acedemic sense, should be earned. It is not just a given.
No problem, you can continue to be rude then, to anyone who disagreed with you.

QuoteQuote:
In an sRGB color space basis, for a chromaticity neutral (“gray”) scene), this
would correspond to RGB values of about 113,113,113.[/COLOR]
HOW you can still deny this FACT is beyond me...
Okay again, show me how your *ist D exposes to 113 accurately and consistently then, even given the 113 value is the mid-grey (which is just not the most crucial IMHO). At least my *ist D bodies have never exhibited enough accuracy and consistently. Just a quick switch to the CWA or Spot modes will easily push exposure under far below 113 and with particular digital lenses the case was even worse.

Still, I think for anyone who just don't believe, continue to look at the posted sample photos at Ned Burnnell's Blog and see how much +EV exposure compensation he needed to apply from time to time *consistently* even with his newest K20D in order to take the nice-looking pictures he presents.
06-16-2008, 09:03 AM   #49
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QuoteOriginally posted by RiceHigh Quote
No problem, you can continue to be rude then, to anyone who disagreed with you..
nope, reserve that honor just for you.


QuoteOriginally posted by RiceHigh Quote
Okay again, show me how your *ist D exposes to 113 accurately and consistently then, even given the 113 value is the mid-grey (which is just not the most crucial IMHO). At least my *ist D bodies have never exhibited enough accuracy and consistently. Just a quick switch to the CWA or Spot modes will easily push exposure under far below 113 and with particular digital lenses the case was even worse.

Still, I think for anyone who just don't believe, continue to look at the posted sample photos at Ned Burnnell's Blog and see how much +EV exposure compensation he needed to apply from time to time *consistently* even with his newest K20D in order to take the nice-looking pictures he presents.
Never said my D was a 113. And you know very well that my "white wall" tests peaked at 90. A 90 ( a consistent 90 BTW) EVEN after getting it repaired and recalibrated at Pentax.
unlike you I concluded, and from NUMEROUS inquirerys, that it was just the way it was designed. And to be honest, I do like it that way. I used to shoot slides and found the metering to my liking. not only that the D has wonderful range when you stretch the histogram out. I find pulling both the wp and black point to the end of clipping is MUCH more appealling to me than a straight exposure boost.
And I told you (check out Daniella) I checked a lot of Canon bird shots and almost every one had - EV dialed in. Your proof is a non-proof when placed in the vacuum of your logic.
-2/3 EV
IMG_9695b3s.jpg photo - Daniella T. photos at pbase.com
IMG_2513d3s.jpg photo - Daniella T. photos at pbase.com
-1 EV
IMG_4665gg2s.jpg photo - Daniella T. photos at pbase.com
To reiterate and quote my favorite Leica "guru"
'The exposure meter is calibrated to some clearly defined standards and the user needs to adjust his working method and his subject matter to these values. It does not help to suppose all kinds of assumptions that do not exist.'

Erwin Puts



Last edited by jeffkrol; 06-16-2008 at 08:00 PM.
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