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May 10, 2011

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When you have as many options as on a modern DSLR absolutes are hard to pin down. For people who like to pick up a camera and just shoot, these are not the cameras for them. There are simply so many ways of not getting what you want.

I can sympathize with camera manufacturers though. Those options exist on these cameras largely because very vocal users (though maybe not a majority) demand them.

As cameras like the Fuji X100 (and the enduring popularity of Leicas) are proving, maybe sometimes you just need to break the options down to their simplest components.

Choices mean complexity (and unhappy users). Sometimes we need the absolutes of having no options to configure. This way if there is a problem with exposure you no longer have the option of blaming the camera : )

I'm not sure why anyone would want to use matrix metering for scenes with extreme contrast. The spot meter is there for a reason! Even my point and shoot has one.

I think one needs to start deciding on a desired exposure based on an assessment of the scene to be composed in terms of its histogram:
a) some landscapes (without sky) might be best with partly lit grass around Zone V
b) some portraits might be best with the central lump around Zone VI
c) multi-subject scenes such as your samples above need some form of (weighted) average exposure

The key to these is to look at the shape of the histogram: quite a lot of subjects will approximate a gaussian/normal distribution. It is this shape of histogram that the camera will try to average around a midtone, which gives it the greatest contrast-spread and scope for manipulation (hence why EttR is not always wise). Your sample scene, however, has a histogram with a lump towards the far left (obviously the leaves) and then clearly separate split-channel r/g/b peaks towards the mid/right corresponding to the building (slightly reddish) and sky. I'd say that puts it into category "C" above, where there's much subjectivity in how you weight the relative exposures for each component subject. (Even with the common symptoms above, maybe you can settle for 1% by area of any one channel pegged; maybe you don't.)

Sure I think it looks nicer in the lower one, with some light coming through the leaves.

So the nerdy answer would be to guess and then chimp the histogram at source and then, since it appears to be necessary, exposure-bracket for HDR by some choice of algorithms that gives the effect of "folding" the highlights & shadows back toward a midtone (like the highlights & shadows tool, like most tonemapping tools, like enfuse). That way there'd be an exposure with no noise in the leaves *and* one with unblown highlights and all would be well apart from the ghosting in the breeze ;)

If it weren't for the fact that the D7000 is so happy to blow highlights, I'd agree. But when you're talking about blown highlights, you're talking about having gone beyond as far as it should have gone. Clipping = too far. Otherwise, yes.

Granted, the problem mostly exists for in camera jpegs, but therein lies the rub.

The D7000 has the ability to shoot jpegs, but it will often overexpose them in an effort to keep the noise as low as possible in the darker areas. So, you can shoot jpeg. But can you use the jpegs you take?

And the D7000 has the ability to use picture control profiles, but only if you shoot in jpeg (which the meter will often overexpose) or if you're shooting raw AND using Capture NX. Shoot raw and use Aperture 3? No picture control profiles in your raw files. Want to shoot jpeg then? Fine, but they may get overexposed.

Bottom line: if you shoot raw using Capture NX for post, you're probably safe. If that doesn't match your workflow... you're probably better off not upgrading to a D7000.

What I find particularly disappointing is that this is a software problem that could most likely easily be fixed. Again, to be clear, I'm not suggesting that exposing to the right is bad. I'm simply saying that exposing to the right to the point of blown highlights is an error. I have no Doubt Nikon will indeed fix the metering. But I think that fix will come with the D7100 in 2012 or 2013. D7000 owners will never see it. Hopefully I'm wrong about that.

By the way, I'm not sure the overexposure is strictly a matrix meter thing. I think it's a jpeg thing, regardless of the metering mode. RAW files still clip, but they're mostly recoverable.

So there you have it, folks. Rob's original comment, my response (which wasn't intended to disprove Rob's opinion but rather to offer objective evidence that supports both sides of the issue), and Rob's counter-response. Assuming you care at all I'll let you make up your own minds.

Gordon,
I haven't had my K5 very long, so I haven't come close to trying all of its options yet. But yesterday, I was using it to shoot "product shots" for the famous auction site. I was having some trouble getting proper exposure on both the chrome and the black leatherette on a camera. As an experiment, I turned the contrast all the way down on the "Neutral-Vivid-etc" menu.
This results in jpegs that look pretty awful out of the camera, but it's easy to selectively increase the contrast in PS.
Haven't had a chance to try this outside yet (it's pouring rain) but I'm wondering what you would think of this as a way of dealing with very contrasty sunlight/shadows. Of course, you wouldn't have to turn the contrast all the way down. Just a nudge. It's a little like pulling film, and then printing on #4 paper.

I shoot jpegs, almost exclusively, on a Pentax K10 using matrix metering. I have not noticed any tendency towards overexposure. I come from a background of slide shooting and so learned to second guess my meter and when to apply over or under exposure to achieve the results I want. This is only necessary when you want to override the matrix meter and decide whether you want an image with (mostly)mixed lighting to appear on the lighter or darker side. One thing I have noticed is that the matix meter is hardly responsive to 1/3 increments of over or under exposure in even light, so I now use 1/2 stops to achieve what I want. Really, the matrix meter is a tool and what one needs to learn is, how does it behave?

I have been fretting and fussing for quite some time about which camera to get, the K5 or D7000, but now the time has come. I had an accident on the weekend and broke my dear K10. I am surprised it and my lens did not smash into pieces when it hit the rocks hard. But it is unrepairable all the same.

Soon, my friends, soon...

>>I turned the contrast all the way down on the "Neutral-Vivid-etc" menu... I'm wondering what you would think of this as a way of dealing with very contrasty sunlight/shadows.<<

I think it's a great idea and wish I had thought of it. As you say, just a nudge (one or two increments) should do it. If you go too far you might later posterize the image if you use a curve to boost the contrast back to where you want it.

Anyone wishing to try this should also keep in mind that not all JPEG picture styles have the same default contrast setting. The neutral, faithful, and standard settings are generally lower in contrast than the vivid and landscape settings. Experiment to see what works best and which you like most. The less tweaking you have to do to any given JPEG style, the better.

"It's a little like pulling film, and then printing on #4 paper."

Oops. Pretty much gave away my age there.

I'm a bit late to this party, but there's an easy solution to Rob's problem: Custom Setting Menu -> b Metering/exposure -> b5 Fine tune optimal exposure and then dial in whatever adjustments you want for the different exposure modes. I've set mine for -1/2 stop across the board, FWIW.

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