I’ve decided to break my D7000 vs 7D ambient exposure evaluation into separate articles/videos. First up is the age-old question, “Does the Nikon D7000 overexpose?” Well, age-old in terms of internet time anyway. There’s been lots of people complaining about this online, particularly for bright outdoor scenes, and many have blindingly-bright, flat, and washed-out photos to show for their troubles.
Some people agree with them. Some don’t. Some even tell these hapless photogs they don’t know how to use their camera, a response I’ve always found curious considering that the whole idea behind an evaluative/matrix metering system is to fully automate exposure decisions in as many situations as possible. It seems to me that landing short of this goal should be regarded as a shortfall in design rather than something the user is doing wrong. That’s not to say it’s reasonable to expect an AE system to nail exposure for every conceivable scene, particularly scenes where the dynamic range exceeds the camera’s abilities or when “proper” exposure is more of a subjective judgment call (those two are one in the same for many cases). But how about something simple, like a medium-contrast landscape? (simple, eh?)
In part one of this three part video, I start with a discussion of the basic methodology I used for comparing the exposure systems between the Canon 7D and Nikon D7000. Part two dives right into the overexposure issue, using differential analysis of some landscape photos taken with both cameras. I finish up with part three, an old-fashioned snow fight!
Part 1 (Introduction/Methodology)
Part 2 (D7000 Overexposure?)
Part 3 (Snow Fight)
I’d appreciate it very much if you could address exposure when shooting in jpeg at some point. Shooting in jpeg doesn’t mean the shooter does no post. I tend to shoot jpegs because of the difference in file size. I work on the web and find that jpeg files are so much easier to work with in Aperture 3 than raw as they’re substantially smaller. While I would expect a greater level of control with a raw file, I shouldn’t expect different exposure, should I? Jpegs get blown out but raw don’t? Is that part of the takeaway here? I’m having trouble believing I’d get better jpegs with a D5100 than a D7000, but that’s looking like it may be the case.
Hi Rob,
The exposure for the raw and jpeg are technically the same; the difference regarding clipping is due to the specific tone curve applied. The data in a raw file is linear, meaning each doubling of light is reflected by a doubling of the values in the raw data. However, human sensory perception (sight and sound) is logarithmic, so it takes orders of magnitude of more light for humans to perceive a doubling of light. That’s where the tone curve/gamma comes into play; it converts the linear raw data (which is much darker if you were to look at it without gamma correction) and applies a gamma function to it based on the model of human sensory perception. This gamma function increases the “apparent” exposure (brightness is a better word) at varying levels across the specific tone curve being used.
For the faithful picture style (and its associated tone curve), the gamma adjustment are still keeping the highlights within JPEG clipping (JPEG/TIFF is the gamma-adjusted output after the curve is applied, either when it’s done inside the camera for shooting JPEGs or inside Lightroom/Aperture when you import a raw file). Other picture styles, like Landscape/Vivid, apply a tone curve with more contrast, which requires crushing some of the shadows and boosting the highlights, to make room in the curve for increasing the contrast for the midtones.
The difference for raw is that you can control this tone curve after the fact, and more importantly, allows you to control other image adjustments that will affect how the tone curve acts on the raw data. The most important of these adjustments is the black level, which allows you to push the highlights/mid-tones into the direction of the shadows, leaving more headroom available in the highlights to accommodate a contrasty tone curve without inducing highlight clipping. This is particularly important for medium-contrast scenes like the one I analyzed in the video.
Your point about doing post-processing on JPEGs is a fair one. I didn’t mean to imply that JPEGs can’t withstand any post-processing, but instead that they can withstand much less processing, since you lose out on the raw adjustments like black-point, and also there’s less tonal range so posterization is much more likely.
I plan to do a future video demonstrating some of what I discussed above.
I use D3s mostly and recently acquired a D7000. There is clearly a perceived or real brightness issue especially with matrix metering. Bottom line is it advisable to apply a negative adjustment in the fine tune menu item. Will this prevent clipping. I do not want to think about clipping on every shot
Just bought a D7000. When I saw the first bunch of shots I just about cried. Noisy, overexposed, horrible!!
In bright landscapes it is obvious that you have to dial in exposure compensation.
I’m trying to resist the urge to take it back for a refund. The Canon 7D looks really tempting although $500 more. I guess there is a bit of a learning curve – for example, I’ve taken some indoor still life shots with the 35mm F1.8 which are beautiful. I find that using jpeg large fine the limitations of the sensor and lens become apparent. Probably a full frame camera is going to come up with a better result.
Here is a landscape taken with my $500 Canon S5is
http://www.flickr.com/photos/mahamantra1/5725971528/sizes/l/in/photostream/
Here is something I just shot with the D7000. I’m a little puzzled why the shot/s seem grainy?
http://www.flickr.com/photos/mahamantra1/5732697189/sizes/l/in/photostream/
Can someone more knowledgeable comment on this?
Hi Steve,
Your D7000 photo appears underexposed, which will cause the noise you set. It’s also not clear what ISO the photo was taken at (no EXIF data).
-adam
Fantastic presentation….. very informative.
My question is is this: The D7000 in-camera histogram is based on the jpg picture control (I think). How do I gauge if the RAW image is clipping when I’m in the field? That is, how do I know I’ve exceeded the D7000’s raw DR when I’m using a jpg histogram?
Thank you!!
Hi Adam, I have a new question involving the effect of ADL on my D7000. I had noticed that my D300 appeared to have a little better highlight dynamic range than the D7000. Is it wise to use the ADL, or could I do better using the neutral picture control setting to get more shadow range, and underexposing by whatever amount I need, and lifting the shadows later? I’m judging by the graphs I saw at dpreview, on the neutral picture contol, and ADL settings. Thanks, Bruce