Comments on: Overexposure and Underexposure, and the Compensation Thereof

By: Caroline W

Caroline W — Tue, 22 Mar 2011 02:36:17 +0000

WOW,this is amazing and VERY informative for an absolute”kiwi ‘beginner like me..thanks for this post

By: Sean McCormack

Sean McCormack — Thu, 09 Jul 2009 00:38:15 +0000

Nicely put together Jeffrey. Hopefully Engadget don’t steal this one..

By: Brad Wiederholt

Brad Wiederholt — Sun, 17 May 2009 22:46:16 +0000

Jeffrey — you put a lot of work into the post — thanks for that. I was just looking around for some examples of “exposing to the right” and came across the post. Seems to me that the +1EV raw when adjusted down really does offer up more overall detail, but it also seems to lose a bit of contrast as well? Interesting. Thanks for the post — Brad

By: Andrew S

Andrew S — Fri, 06 Mar 2009 09:00:22 +0000

That’s a great example. I liked the -2 EV shot the best.

Actually, what i mean to say is that is a great example of the kind of shot where digital cameras still fall short of film. I think the point and shoot olympus film camera that i grew up using would have done a better job with that shot than a D700, because high exposures of that sort look better on film.

The DSLRs are improving faster than film, though

By: Matt Dawson

Matt Dawson — Mon, 02 Mar 2009 01:57:46 +0000

Great post! It just goes to show that while there is no substitute for a good initial exposure, shooting RAW is the next best option for us serious hobbyists who need to recover from "exposure disasters" (and white balance disasters) a little more regularly than the pros. I'd previously seen Ken Rockwell's advice on JPG vs RAW and thought it was a little simplistic in describing who should use RAW and why. You've demonstrated it allows people still working on their photography skills to recover photos that would otherwise be unusable.

By: Zachary

Zachary — Sun, 01 Mar 2009 11:15:07 +0000

I leave my camera on Auto WB and get usually good results in my JPG shooting. Sometimes I tweak the WB in Lightroom, but I’ve never noticed any artifacts from this.

What I’ve wanted to do for a while is perform the same kind of experiment as Jeffrey’s above but with WB: take a perfectly balanced photo, then take JPGs incrementally removed from this optimal white balance. Say, one JPG per 100 K WB. Then “normalize” the off-kilter photos in Lightroom and see at what point artifacts creep in.

By: Awake

Awake — Sun, 01 Mar 2009 10:16:02 +0000

For me the primary problem with shooting JPEG is not the exposure latitude, since modern cameras seem to come pretty close in their exposure decisions, and except for recovering blown highlights and extreme exposure adjustments, RAW doesn’t seem to be a big factor during processing for me. What I find most important about RAW is the ability to control color, be it ‘Color Temperature’ or individual color adjustments. With JPEG, the colors seem to be much more ‘baked in’ to the image, and adjusting a photo that was significantly misjudged at the time of exposure becomes very difficult. Since with RAW the color is not ‘baked-in’, making color adjustments is much easier and provides much better results.
I tend to photograph under varying mixed artificial light (theatrical lighting), where the cameras seem to always misjudge color temperature, and shooting JPEG has become a taboo. I cringe every time I have to go back to a photo taken 3 years ago when I was using JPEG, knowing that adjusting the colors will be a real ordeal.

I couldn’t agree more, except that I’m a sufficiently poor photographer that raw’s latitude in correcting exposure mistakes is a big benefit for me. As I get better, that benefit is reduced, but since I feel no need to pay attention to white balance while shooting, that’ll always be a great benefit for me. —Jeffrey

By: Zachary

Zachary — Sat, 28 Feb 2009 22:46:52 +0000

@Jon – From a noise-control standpoint you are correct, but in terms of recovering detail you have more latitude when underexposing. As everyone knows, this is due to the linearity, polalarity, and the nuclear resonance characteristics of the gummy bears from which they fabricate the sensors.

By: Jon

Jon — Sat, 28 Feb 2009 17:28:43 +0000

@Ron – An overexposed shot that can be brought down will be much cleaner than an underexposed shot that is brought up. It’s better to tone down the highlights than amplify the shadows, from a noise standpoint.

By: Zak

Zak — Sat, 28 Feb 2009 15:53:27 +0000

Regarding why underexposure works better, here is what Tom Hogan has to say in his excellent manual on the D90 (similar manual available for D700 etc.):

Post-processing exposure changes are also more easily made with NEF [RAW] files (these are not really exposure changes, but changes of the linearity* of the exposure, which is why it works better to correct underexposed images instead of overexposed ones)…

That astrix indicates a long footnote that describes what is meant by linearity, but I’m too lazy to re-type that here.