Underexposure Issue k10d

the two candles in the centre of the frame will cause underexposure as Pentax is heavily biased against blowing highlights. Seemingly small bright spots like these have a disproportionate effect on exposure.

It looks like the correct exposure would have pushed shutter speeds so low that motion blur would have been a problem. You probably need either a faster lens or to go to a higher ISO.

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Steve

http://www.pbase.com/steephill

Steve is probably right. For some reason I haven't been able to load the pictures so my replies are based on a lack of info.....
GMT minus 8



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I really wish the manual defined the way in which the camera determines shutter speed in auto mode. Does it have any relation to the lenses focal length? Is there a defined minimum?
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Pentax k10d, Pentax 50-200, Sigma 18-50 Macro soon...

Well I am waiting on that 18-50 f 2.8 sigma. But honestly I don't think 1/40 second would have been a real problem.
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Pentax k10d, Pentax 50-200, Sigma 18-50 Macro soon...

generally it will try to keep at least 1/focal length if possible. The other options such as MTF try to use the best performing aperture, the so-called "sweet spot", which is encoded in the lens chip. The manual does have some information about this but it could be better written for sure.

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Steve

http://www.pbase.com/steephill

Did you have the camera set up on a tripod? re if you've If so, did you cover the viewfinder? I have had this problem once, when extraneous light entered through the viewfinder, as I did not have my against it, and caused underexposure. Far safer to use manual exposure if you're eye's not up against the viewfinder.

Allan

It is amazing how many times this has come up and how many times people seem to side step the problem. The problem isn't that you can take a meter reading and then go in a mode like manual and adjust from there to get the proper exposure.

The point is that like the K100D which also seems to have this problem the K10D under exposes in full auto mode. That is the issue, not how one can get around the problem.

Are people so afraid to find out that their perfect camera isn't that they totally side step issues like this, the white balance issues and the noise banding issue? Seems crazy to me.

Robert

Well, I will give the K10D credit. When it under exposes it really under exposes.

Robert

If you download the istD manual, there are the program curves at the end of the maunal somewhere. Instructive. Unfortunately they left this out in the K10 manual.

Is is possible the person pushing the shutter button for you accidentally touched something or touched something on purpose?

Robert

It was set up on a tripod, but this business with light going in through the viewfinder seems highly suspect... How would it hit the sensor?
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http://picasaweb.google.com/chrswggl

Pentax k10d, Pentax 50-200, Sigma 18-50 Macro soon...

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At least you're consistent.
GMT minus 8



Without gravity, what would we do with water?
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The light entering the viewfinder does affect metering. If it's stronger than the photographed scene, this may explain why the picture is so much underexposed.

You K10D manual must contain some caveat for these situations.
jpmar
' http://imageevent.com/jpmar '

Allan Taylor said:

Did you have the camera set up on a tripod? re if you've If so, did
you cover the viewfinder? I have had this problem once, when
extraneous light entered through the viewfinder, as I did not have
my against it, and caused underexposure. Far safer to use manual
exposure if you're eye's not up against the viewfinder.

Click to expand...

I think you hit the nail on the head Allan. That's the missing piece in this puzzle.

--
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Light meter panel is attached to the back side of the pentaprism. There's a pretty straight shot from the viewfinder to the panel. Light entering the VF WILL cause meter errors....
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360 minutes from the prime meridian. (-5375min, 3.55sec) 1093' above sea level.

'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

Only occasionally am I reminded that I might have learned a thing or two in this life. Perhaps this is one such occasion.

Cameras get more and more power and more and more capability, but I'm not convinced they get smarter or wiser. Instead, the photographer is the one who needs to get wiser with regard to knowing when the camera is capable of doing the heavy lifting (the thinking part) and when it needs to be lead by the hand like the poor dumb creature it sometimes shows itself to be. I've come to regard feature-laden cameras a bit like a calculator in the hands of a 5th grader. It's all well and good to let him have the tool to sidestep the drudgery of long paper and pencil calcuations, but it can be a mistake unless it comes at the end of a learning curve that was climbed the hard way, hand over hand through the logical and mechanical steps of arithmetic operations.

ASSUMING there's no actual fault in the camera - faulty or failed parts or circuits - then you have to take it on faith that the camera was following a carefully structured set of rules for making exposures. The trick is to be able to follow your own decision process and see if you and the camera are at least thinking along the same lines.

I just re-read that and LORD, that sounds pompous.

This sounded more like a sermon than a response to your question. The only thing I have that comes close to a response is to say that I really learn a lot from using a Sekonic incident meter to help me understand the lighting. Outdoors it's pretty easy, especially on overcast days. Indoors, you'll find lots of variation over very short distances. If you're using reflected light metering you absolutely MUST consider the brightness of your subjects to a middle-gray tone. Thumbnail rule: Overrule the meter by overexposing bright objects and underexposing dark objects.

Stu

Read the quote in my sig
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360 minutes from the prime meridian. (-5375min, 3.55sec) 1093' above sea level.

'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

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Steve

http://www.pbase.com/steephill

If I understand correctly, this will change the exposure based on what the camera focuses on. The scene is relatively flat though and in a basically similar light level. I don't think this would cause a problem. i may be wrong though.
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http://picasaweb.google.com/chrswggl

Pentax k10d, Pentax 50-200, Sigma 18-50 Macro soon...