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11-09-2008, 09:05 PM   #46
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My K20D has Flaws? That is the first I heard of this.

11-09-2008, 09:44 PM   #47
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QuoteOriginally posted by k100d Quote
it's a common complaint that the pentax underexposes.
i might not be an expert at exposure, but i find that it happens to me a lot.
Of course it is common for a DSLR to produce a darker exposure than what one wants. Happens to me to when I don't think about where to meter or what kind of compensation I need to apply in order to get the exposure I want. That's not underexposure - that's just a matter of the "correct" exposure for how we are are metering being darker than the one we happen to want.

Feel free to post sample shots. It's usually quite simple to demonstrate how the exposure chosen was the brightest that would avoid clipping, or that the average luminance is right where ISO standards say it should be.
11-09-2008, 10:03 PM   #48
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QuoteOriginally posted by fs999 Quote

Live view is a nonsense for a reflex camera... There are other solutions like an add-on with a small video camera to put on the viewfinder with a detached bigger screen or buy a compact...
Are you sure? I happen to use it often enough with my Olympus... nonsense? I'd say more like inevitable and handy.
11-09-2008, 10:08 PM   #49
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QuoteOriginally posted by rburgoss Quote
OK, I'll bite: Is this a serious question?

Otherwise, the ONLY thing I would like on my K20D that doesn't have, is a way to turn off noise reduction (or whatever hangs it after shooting long exposures).

RB
Mine's on order, but this NR thing is the only major reason I want to keep my K200d when the K20d arrives. I assume this is fixable in the firmware, but I suppose not enough people have complained. For a one or two minute exposure, it's gonna be a major pain to wait the next one or two minutes to be able to use the camera... and imagine trying to do star trails.

11-10-2008, 04:12 AM   #50
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So, you should see these!

QuoteOriginally posted by Marc Sabatella Quote
Also keep in mind that while he says that some number of users report problems with exposure inaccuracy, that number goes down to essentially zero if you exclude the people who don't actually understand exposure (including RH). That is, the people who report exposure problems are the ones who erroneously think that merely pointly at a scene and pressing the shutter should invoke a magic "mind reading" mode where the camera produces exactly the exposure you want for the situation, rather than the exposure that every book on photography will tell you that you should *expect* for the situation.
http://dc.watch.impress.co.jp/cda/review/2008/11/06/9544.html

The K20D underexposed for all test shots in the same test scene. Even after a +0.3EV exposure compensation, the resulted photos are still looking darkest. Lens used is the latest kit DA 18-55 AL II.

Also, DPR technical writers are not knowing well how to use the K20D as they applied the most exposure compensations for the shots they made, when they tested the K20D! (but other models are better!?)

http://ricehigh.blogspot.com/2008/06/k20d-exposure-inaccuracy-and.html

Or, as you said, the K20D read the minds of those DPR technical writers worst!
11-10-2008, 04:20 AM   #51
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Possibly In-born Hardware Problem

QuoteOriginally posted by heliphoto Quote
Mine's on order, but this NR thing is the only major reason I want to keep my K200d when the K20d arrives. I assume this is fixable in the firmware, but I suppose not enough people have complained. For a one or two minute exposure, it's gonna be a major pain to wait the next one or two minutes to be able to use the camera... and imagine trying to do star trails.
The firmware is designed as intended, not a bug or something needed to be fixed.

It is just because the firmware is used to hide the hot pixels, without the dark frame subtraction, the results must be terrible otherwise Pentax would have already decided to let the user have the option.

More info:

RiceHigh's Pentax Blog: K20D is Still "Hot" with Firmware 1.01

RiceHigh's Pentax Blog: Issue of Hot/Dead Pixels of the K20D

RiceHigh's Pentax Blog: Dynamic Range and (Background) Noise Tests of the K20D

So, unless the Samsung 14.6 MP CMOS sensor can be improved to become not that hot and noisy, no firmware could actually do the magic!

Just for this hot pixel issue, which is most likely a hardware one, I will not consider to get a K20D no matter how cheap it becomes, especially I like to shoot night scenes much.
11-10-2008, 04:30 AM   #52
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Every camera has flaws

QuoteOriginally posted by Fl_Gulfer Quote
My K20D has Flaws? That is the first I heard of this.
Some have more and some have less. Some flaws are more serious and some are less minor.

A camera with no flaw? Is really any such perfect thing in this universe??
11-10-2008, 04:43 AM   #53
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My K20D is about a month old now, and during my gigs, a Canon friend of mine uses it to shoot us onstage. He is now seriously considering shifting to Pentax... I don't understand why people complain about the slow focusing, even my Canon friend is impressed with it (though it is a bit slower than canikon, it still performs ably in low light). My other bandmate (who owns a D300) also lets my friend use his camera to shoot us, but my friend still prefers the K20D over the D300... my only gripe so far with the K20D? The NR for long exposures and that's about it... oh, and the lack of an FA* 80-200/2.8 attached to it.

11-10-2008, 08:24 AM   #54
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QuoteOriginally posted by RiceHigh Quote
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The K20D underexposed for all test shots in the same test scene. Even after a +0.3EV exposure compensation, the resulted photos are still looking darkest. Lens used is the latest kit DA 18-55 AL II.
WHAT metering mode?


QuoteOriginally posted by RiceHigh Quote
Also, DPR technical writers are not knowing well how to use the K20D as they applied the most exposure compensations for the shots they made, when they tested the K20D! (but other models are better!?)


RiceHigh's Pentax Blog: K20D Exposure Inaccuracy and Inconsistency

Or, as you said, the K20D read the minds of those DPR technical writers worst!
GARBAGE study and statistically insignificant, not to menton flawed premise.
Re: The image. note that it has it's contrast range truncated. Wether you want to call that an exposure error or not, the photo has headroom..

Last edited by jeffkrol; 11-10-2008 at 09:17 AM.
11-10-2008, 09:43 AM   #55
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QuoteOriginally posted by daleroy Quote
I've actually used all three cameras and I can tell you that the 400D and the 40D are quicker at focusing. My sister owns both of them and I have the K20D. When using the Tamron 28-75mm lens on the 40D and the K20D and attempting to lock focus on something inside, the 40D won hands down, every time. Half the time the K20D didn't even lock focus, just kept hunting. My wife and my sister and husband have all played with all the camera's and they all say the same thing, that the K20D is a lot slower to focus indoors. Outdoors there isn't as much in it, but it's still slower. The 40D especially has a very swift solid focusing feel to it. It just locks into position very fast.

Have you used a 40D before? If not, try it before telling my I'm spouting crap.
two points

the canon version and the pentax version of this lens focus differently (AFAIK). Canon's implements an internal motor, pentax relies on its body motor.

it has been somewhat established that Pentax has a very strict focusing algorithem, its easier to focus faster when your error variable is 2-3 times as large.

my friends Canon 30D focuses fast, but many times the photo comes out OOF so..
11-10-2008, 10:44 AM   #56
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QuoteOriginally posted by RiceHigh Quote
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The K20D underexposed for all test shots in the same test scene.
I don't read Japanese nor do I trust automatically generated translations, but looking at the pictures, I might assume the text is saying, "see here, the K20D is the only camera that didn't blow out the highlights". Which is to say, it exposed perfectly, the others overexposed. And not just a little - they overexposed *horribly*.

It's obvious enough to the naked eye, but if you really need proof, download the E-520 sample and look at the histogram. Can't you see that giant spike along the right side showing how badly the image is clipped? If you still have any doubt, click an eyedropper anywhere in the broad white building (at least, it looks pure white in the E-520 picture, because it has overexposed so badly) with the word "Conrad" on it. I don't think there is a single usable pixel anywhere on the face of that building - they are virtually *all* maxed out at 255,255,255. The E-520 managed to complete wipe out all detail on that building - it looks like a solid mass of white. The others were only marginally better, showing only the faintest hint of the brickwork. These are almost *comically* bad.

The Pentax picture was the *only* one not to blow out most of the detail! And if you look at the histogram, you;ll see it it is within a quarter stop of clipping. meaning it completely *nailed* the exposure here - it could not have exposed any more without ruining the picture a badly as the others did.

I mean, really, if you wanted more definitely proof of how *great* the Pentax metering is, don't think you could do better than this example! Please, for anyone still harboring even the slightest doubt, clicking on that link and then view the K20D picture from the first set.

The fact that you can look at those pictures and not see just how badly the other cameras are overexposing the scene and that Pentax has nailed it perfectly is but one piece of evidence that you do not understand the first thing about exposure.

QuoteQuote:
Also, DPR technical writers are not knowing well how to use the K20D as they applied the most exposure compensations for the shots they made, when they tested the K20D!
And the fact you believe that needing to apply exposure compensation for some scenes is indicative of a problem is yet more evidence that you don't understand the first thing about exposure.

But thank you for posting this link to the perhaps the most conclusive proof I've ever seen of just how bad other camera's metering can be, and just how off-base people can be in claiming Pentax is underexposing.

Last edited by Marc Sabatella; 11-10-2008 at 11:03 AM.
11-10-2008, 11:02 AM   #57
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Here is what I am talking about. These are crops from the pictures on the site RiceHigh mentioned, I don't know if I could have found a better example myself to prove my point.

Here is the Nikon D90:



And here is the K20D:



Can you imagine a more perfect demonstration of how just badly some other cameras will *overexpose*? The K20D managed to preserve all the detail (as the histogram in Jeff's post demonstrates), and as you would see if you took the K20D image into PP, it couldn't have gone even an additional third of stop higher without starting* to clip. After half a stop, it would have looked almost as bad as the Nikon. That is, the K20D exposed this scene *perfectly*, and was indeed the only camera test to do so. Not all blew it as badly as the Nikon, but no one came *close* to doing as well as the Pentax.

Now, it is true that maybe you didn't care about the detail in that building and would rather have blown it out in order to get some other part of the scene looking how you wanted. That's a legitimate choice - but it is a choice for you to make, using the exposure compensation controls (or by using spot metering and/or by using M mode to set exposure as you see fit, using the camera's meter as a guide). This is what I mean about the camera not reading minds - it should never *assume* you want to blow out highlights as badly as Nikon did here.
11-10-2008, 11:11 AM   #58
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discussing exposure in digital cameras in my opinion is a moot point


first, you have an exposure compensation dial that goes +/- 2 or 3 stops (some of the higher model cameras go like 5 stops i think?)

second, you have 3 parameters to chose from, spot, center, and full


with such controls at your disposal its rather bleak trying to argue which camera exposes the best.

we have been blessed with a histogram right there in the camera, you take the shot, you judge it, you adjust accordingly.


in the past you had to learn how to read scenes, and pay attention to really fine details to get the correct exposure.

now days people want a camera that will automaticaly do everything right for you... and you want this camera to cost less than 10 bucks? honestly now guys...


any exposure problems with digital cameras is user error, IMO, unless your camera is broken.
11-10-2008, 12:02 PM   #59
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FWIW, a friend w/ a D80 constantly complains his camera overexposes on outside scenes, so he's dialed in -1 ev permanently. We met up and compared my K10D's metering and it was blowing highlights a *lot* less.
The only thing I can think of is Nikon tried to expose to the right to preserve detail (there's less noise pulling back overexposed RAW images than increasing lighting on underexposed images) and overdid it. The D200/D300/D700/D3 don't have this issue. Must be a "feature" they built into the D80/D90 ;-)
11-10-2008, 01:08 PM   #60
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I'm with Gooshin. The cameras do a great job most of the time -- alongside that you use your intelligence as a photographer. Next issue?
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