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12-07-2014, 04:34 PM   #1
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General underexposure problem with K-50?

Anyone else notice a general tendency to underexpose with the K-50? I usually shoot P mode, auto iso, matrix exposure and focus, but sometimes use shutter-priority and fixed I-SO for sports photography, using the kit 18-55 and the 55-200 zooms. Shots I took in P mode at BSA Sea Base all needed tweaking in lightroom because they were too dark. I'm tending now to just keep it on +2/3 EV to brighten things up. My firmware is 1.00, I don't know if there is an upgrade and whether or not that would help.

12-07-2014, 06:54 PM   #2
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QuoteOriginally posted by OldChE Quote
Anyone else notice a general tendency to underexpose with the K-50? I usually shoot P mode, auto iso, matrix exposure and focus, but sometimes use shutter-priority and fixed I-SO for sports photography, using the kit 18-55 and the 55-200 zooms. Shots I took in P mode at BSA Sea Base all needed tweaking in lightroom because they were too dark. I'm tending now to just keep it on +2/3 EV to brighten things up. My firmware is 1.00, I don't know if there is an upgrade and whether or not that would help.
I have not noticed a tendency. You may want to post some pics with intact EXIF data. I could see where it could be easy to underexpose with shutter priority and fixed ISO, and those are pretty slow lenses. You are depending on the aperture to adjust your exposure and maybe it's just not bright enough, especially if you are indoors. Anyway, there are a lot of people on here that can analyze your photos with the EXIF data.
12-07-2014, 07:23 PM   #3
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I haven't noticed it on my K-30.

Have you tried using different exposure metering modes (centre-weighted or spot)? They can give you more control by picking the area or point that you want the camera to meter from.

Last edited by Des; 12-07-2014 at 09:45 PM.
12-07-2014, 08:45 PM   #4
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Nup, my K-50 does well.
How's your monitor settings?

12-07-2014, 09:13 PM   #5
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QuoteOriginally posted by OldChE Quote
My firmware is 1.00, I don't know if there is an upgrade and whether or not that would help.
Yes, there is an upgrade to 1.02. You can access it here:

Downloads & Literature - RICOH Imaging

The features of the upgrade are covered on the linked page. While it is possible that your underexposure problem may be helped, I don't believe that type of thing was explicitly part of any firmware patch to date.

Metering on Pentax dSLRs has traditionally been bias towards mild underexposure as opposed to risking blocking out highlights due to white value clipping. That leads to a certain gray look in low contrast light. If you are a JPEG shooter you can set the image tone to "Bright" to increase saturation and contrast. If you are a RAW shooter, you can do the same thing in PP. One thing you might want to try is disabling highlight correction. The default is "Auto" meaning that the exposure is set down 1 stop when the camera detects potential for clipping. If your choice of subjects routinely includes large areas of bright overcast or expanses of white, it is likely that many shots are being intentionally underexposed. Turning the feature off may result in the risk of blocked-out highlights.


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12-09-2014, 06:53 AM   #6
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QuoteOriginally posted by Des Quote
I haven't noticed it on my K-30.
With my K30, the kit lens ( 18-55 WR ) seems to work fine. I have had underexposure problem ( perhaps over 1 stop ) with the Tamron 17-50 that I got not long ago. The underexposure was reproducible on my k200D, so I know it's not the
camera body.

When using my DFA 100 WR macro, the K30 seems to have a tendency to blow out highlights. I never had that experience with my K200D. It only happens when the lighting is bright, so it isn't like I can just apply a constant
exposure compensation. I've tried various combinations of metering ( matrix vs centre weighted ) and highlight correction on/off/auto. Perhaps I'll find a combination that works consistently. Eventually.

( and it does matter to me because I do the bulk of my shooting with the macro lens )
12-09-2014, 03:23 PM   #7
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QuoteOriginally posted by arkav Quote
When using my DFA 100 WR macro, the K30 seems to have a tendency to blow out highlights. I never had that experience with my K200D. It only happens when the lighting is bright, so it isn't like I can just apply a constant exposure compensation. I've tried various combinations of metering ( matrix vs centre weighted ) and highlight correction on/off/auto. Perhaps I'll find a combination that works consistently. Eventually. ( and it does matter to me because I do the bulk of my shooting with the macro lens )
I haven't had that experience with my K-30+DFA 100 WR Macro. I suppose you could deal with this in several ways:
- use spot metering and meter for the highlights in very bright conditions
- use a neutral density filter
- use exposure compensation.

To complete the settings test, you might also try various settings for shadow correction (it can affect exposure by up to 3 stops).

Just thinking aloud - I have noticed that sometimes when I first mount a lens it produces overexposure. I wonder whether it could be a little condensation on the front or rear element, or whether the aperture blades might not be moving freely?
12-13-2014, 11:17 AM   #8
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QuoteOriginally posted by Des Quote
I haven't had that experience with my K-30+DFA 100 WR Macro. I suppose you could deal with this in several ways:
- use spot metering and meter for the highlights in very bright conditions
- use a neutral density filter
- use exposure compensation.
I should have added that often, I only have a few seconds to get my shot. I don't have a lot of time to fiddle with different options/filters/etc. If I did, I'd just shoot manual. With my K30, I find TAV
mode works well. Perhaps a combination of exposure compensation and bracketing might be an option ( ie. set moderate compensation, and then apply bracketing to account for when more or less
compensation is needed ). The downside is that this would result in lots of extra exposures, but I guess I could only use compensation+bracketing when I anticipated having problems.

QuoteOriginally posted by Des Quote
To complete the settings test, you might also try various settings for shadow correction (it can affect exposure by up to 3 stops).
I may be mis-remembering, but I was under the impression that it's only the highlight correction that changes the actual exposure, while shadow correction does not.

QuoteOriginally posted by Des Quote
Just thinking aloud - I have noticed that sometimes when I first mount a lens it produces overexposure. I wonder whether it could be a little condensation on the front or rear element, or whether the aperture blades might not be moving freely?
That's a possibility, but if that was the case, one would expect it to manifest itself on my K200D as well.

12-16-2014, 11:07 AM   #9
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I second the highlight correction as the reason. My K50 often underexposes in RAW in LR with highlight correction on or auto. I prefer it that way to avoid clipping, and pulling up the exposure has little negative effect. It does require more fiddling, but then that's what RAW is for :-)

My images look properly exposed on the camera preview.

I wonder if you might try RAW+JPG? The JPGs might be ready for web use out of the can. I imagine they look like the image on the camera.
01-05-2015, 11:09 PM   #10
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Thanks for the suggestions. I'll try to upload some examples (sorry for the delay, busy with the holidays).

As a result of my perception of underexposure, I tried shooting with a +0.3 to +0.7 EV bias. But now looking through those JPEGS (all using default "bright" setting) I see a lot of blown highlights. I tried more recently just using no EV adjustment, and I think the shots are properly exposed, though I would like more "snap".
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