[dieselpunk]

Hello!
I recently bought a used KP as a K-r upgrade and am slowly trying to learn the ins/outs. I'm finding the transition to be easy so far with one exception. The light metering on the KP reads scenes in a way that cause over exposure when there's bright light. I don't mean even mean backlight. This happens the most with direct sun light. The attached picture of my black dog is way brighter than what was actually seen. She is not sleeping with a spotlight on her face! It's like the metering decides that the scene is darker than it actually is and since I'm on Av it lowered my shutter speed to 1/13 and the resulting picture is way over exposed.

This does not happen with the K-r. The resulting K-r image was much truer to life (or at least not drastically over exposed). I've tried changing the AE settings without finding anything that doesn't make it worse (e.g., spot metering) or about the same.

The only thing I've found works is lowering the exposure setting manually to under expose. But that's kind of a pain because I easily forget to set it back. I feel like there's something basic I'm overlooking or not understanding about the KP.

Attached Images

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[AstroDave]

The only thing I've found works is lowering the exposure setting manually to under expose. But that's kind of a pain because I easily forget to set it back. I feel like there's something basic I'm overlooking or not understanding about the KP.

Are you using spot, central, or full-frame metering? (And, it may be different from whatever the mode was in your K-r).

The system is tuned to 18% gray as the expected exposure, in some sense, and will try to make your black dog into a gray dog unless you intervene with some exposure compensation - the under exposure you want to put in to make her blacker/darker (the opposite of the more common case of the camera trying to turn white snow into gray snow - where you need to turn UP the exposure!).

So, yes, you may need to keep fooling with the exposure compensation for overwhelmingly dark or white scenes.

[robgski]

Exactly as stated above. As much as I resort to auto-exposure and Av mode, I know there are time when manual settings or expousre compensation are the better choice.

[c.a.m]

The only thing I've found works is lowering the exposure setting manually to under expose. But that's kind of a pain because I easily forget to set it back. I feel like there's something basic I'm overlooking or not understanding about the KP.

I think you're on the right track with respect to lowering the exposure.

I don't have a KP, so I'm not familiar with its exposure metering. However, I'd say that the lighting in the example image is fairly challenging -- half of the black dog is bright (in harsh sunlight?) and the other half is darker. I would have used spot-metering on the dog's head (assuming that's the main point of interest) and applied about minus 1-1.5 EV of exposure compensation to keep the fur black. Of course, the half of the dog that's not sunlit would be quite underexposed, which could be adjusted in a post-processing program ('lift the shadows').

- Craig

[Mikesul]

In tough situations like this the histogram in liveview can be a big help.

[UncleVanya]

Check the metering mode first.

[stevebrot]

What part of that black dog is over exposed? If there is a wide range of brightness values within the frame, it usually falls back on the photographer to make some decisions regarding expectations and strategy to preserve essential detail and tonal gradation.


Steve

[Not a Number]

Exif data on the above photo shows center weighed metering select. Try changing it to matrix/array. Example photo is mainly black in the center portion. Exposure looks ok to me.

[Fogel70]

Multi segment metering that evaluate the whole scene would most likely do a better job than center weighted metering that meters on the center of the scene.

If using center weighted metering you will have to use exposure compensation more often when the center of the scene is darker or brighter than middle gray.

[chrism888]

Are you using spot, central, or full-frame metering? (And, it may be different from whatever the mode was in your K-r).

The system is tuned to 18% gray as the expected exposure, in some sense, and will try to make your black dog into a gray dog unless you intervene with some exposure compensation - the under exposure you want to put in to make her blacker/darker (the opposite of the more common case of the camera trying to turn white snow into gray snow - where you need to turn UP the exposure!).

So, yes, you may need to keep fooling with the exposure compensation for overwhelmingly dark or white scenes.

Exactly this

[BigMackCam]

Almost two thirds of that scene is taken up by your (adorable) black dog, and the metering system will attempt to raise the metered area to an average of 18% gray. Multi-segment will do a better job of this scene than centre-weighted, which in turn would do a better job than spot... but it's a tricky scene to meter in any of the modes. In instances like this, an incident light meter really comes into its own... or else, Live View with histogram overlay, and adjusting exposure until the right hand side of the histogram curve isn't clipping.

In short, I don't think your KP is doing anything abnormal. You need to assess the scene, estimate the percentage of dark tones vs light tones (here, I'd say it's at least 60/40), and for anything other than 50/50 distribution, use EV compensation to increase or decrease exposure accordingly.

[Papa_Joe]

As has been said, your picture has quite a difficult distribution of tone values with a lot of black in the area, where the center weighted metering will mainly meter.
This leads to an overexposure in the highlight areas. Without your nice dog you would have an underexposure, as bright tones would domniate the scene.

In addition you have recognized that the latest Pentax models have an other basic setting for the metering and the jpeg engine.

In my experience older models did exposure a bit more carefully. This led to pictures that looked or that were underexposured when they had a lot of dark tones. On my K-10D the exposure correction was set to + 0.5 most permanently. In addition it seems to me, that the jpeg engine of the older models had a more film like approach, i.e. highlights were muted, while the newer profile follows a more linear curve when reproducing the light values in the scene.
My experience is that this leads to a lot of blown out higlights in comparison to older cameras. I can say this for my K-70 and my K-1 in comparison to my K-10D.

I do not complaint, because one of the issues I did not like on my K-10D was its constant "underexposure".

However it was not necessary for me to set the exposure compensation of my K-70 to - 0.5. Instead one can use the highlight correction or just set the custom image settings to ones liking.

I would try the highlight correction at first. Switch it on to "Auto" mode. The issue is, highlight correction only works from ISO 200 upwards. Thus you have to set ISO to "Auto" as well and just set an convenient upper value. ISO 200 will do, but I would suggest to select a higher value for your "walk around profile".
With this options allways on blown out hightlights will be no more big issue. Remember, you can allways set ISO to 100 when you want an this will switch of highlight correction as well. Or you store different settings in the user profiles.

As an alternative you can set "Highlight" in the custom picture parameters to a minus value, which will tone down the highlights in every picture.
More info | Give further expression with PENTAX "Custom Image" | RICOH IMAGING

However, the main issue of your picture was the amount of dark values and high contrast. There is a reason, why portrait photographers do not like harsh sunlight.

[Michail_P]

However it was not necessary for me to set the exposure compensation of my K-70 to - 0.5. Instead one can use the highlight correction or just set the custom image settings to ones liking.

I would try the highlight correction at first. Switch it on to "Auto" mode. The issue is, highlight correction only works from ISO 200 upwards. Thus you have to set ISO to "Auto" as well and just set an convenient upper value. ISO 200 will do, but I would suggest to select a higher value for your "walk around profile".
With this options allways on blown out hightlights will be no more big issue. Remember, you can allways set ISO to 100 when you want an this will switch of highlight correction as well. Or you store different settings in the user profiles.

As an alternative you can set "Highlight" in the custom picture parameters to a minus value, which will tone down the highlights in every picture.
More info | Give further expression with PENTAX "Custom Image" | RICOH IMAGING

However, the main issue of your picture was the amount of dark values and high contrast. There is a reason, why portrait photographers do not like harsh sunlight.

Perfectly said. I agree. Highlight correction seems to work fine in difficult scenes. I use an ISO range of 100-800 without problems. Never had an issue with exposure.

[dieselpunk]

Hey folks!

Thanks for all the great responses. I read them all twice to make sure I understood.

1. Somewhere along the way I remember reading about metering to grey but I guess I never had a practical example of that until now. That helps me rationalize what is going on more. As I changed the AE dial I could see the shutter speed drop as I went from full scene (i.e, "pattern"), to center-weighted, to spot so that part makes sense. As soon as I aimed at white or lighter surfaces the speed increased.
   
   
2. Thanks for the live view tip. I never considered that there would be a live histogram that I could use to adjust exposure in real time. What I've tried is to move the exposure bias until the shutter speed is acceptable for the aperture (or the other way) while holding the ISO constant.
   
   
3. The K-r definitely under exposes compared to the Kp. Through the years I've heard others here claim that the K-r under exposed. I never had anything to really compare so I guess I just got used to shooting with that normal.

I've attached another quick snapshot with the multi-segment auto exposure metering and -1 exposure compensation. Ignoring the sloppy focusing, I think it's looking better even with that high contrast background.

[Ausable]

Yes! Now you've got it! Those are exactly the kind of light-metering exercises that are so good for people to do in order to understand the technology.