Expose To The Right

DavidTO

No, this is NOT a political discussion!

In a recent American Photo there was a short article on exposing to the right--of your histogram.

The logic goes that 1/2 of the sensor data is in the brightest stop. The next stop has 1/2 of the remaining information. By the time you get to the shadows you're left with very little information and a lot of noise. This goes a long way to explaining why Gus was having problems here (although he took the photo in question down).

Does anyone have any thoughts on this? Do you use it? It makes intuitive sense to me. I can always deepen shadows without any problem, but try to brighten a shot too much, and man, are there problems!

There's an article on it here.

Andy

DavidTO wrote:

Does anyone have any thoughts on this?

http://www.dgrin.com/showthread.php?t=309
http://www.dgrin.com/showthread.php?t=2220
http://www.dgrin.com/showthread.php?p=255769#post255769
http://www.dgrin.com/showthread.php?t=4583
http://www.dgrin.com/showthread.php?t=11299
http://www.dgrin.com/showthread.php?t=1898
http://www.dgrin.com/showthread.php?t=28497
http://www.dgrin.com/showthread.php?t=26575

DavidTO

Andy wrote:

http://www.dgrin.com/showthread.php?t=309
http://www.dgrin.com/showthread.php?t=2220
http://www.dgrin.com/showthread.php?p=255769#post255769
http://www.dgrin.com/showthread.php?t=4583
http://www.dgrin.com/showthread.php?t=11299
http://www.dgrin.com/showthread.php?t=1898
http://www.dgrin.com/showthread.php?t=28497
http://www.dgrin.com/showthread.php?t=26575

Uh, so, Andy...any thoughts?

pathfinder

Dave,
This is something that does not seem to be widely understood. Michael Reichman's article explains the reasons for exposing to the right - I can never remember the specific pixels and bits, but he explains it very clearly.

http://www.luminous-landscape.com/tutorials/expose-right.shtml

Most of the information in an image is in the first few steps in the histogram on the right. SO, yes I try to keep my histograms to the right, but short of blowing out the highlights of course.

Hedging to the left of the histogram is a sure way to increase the noise in your images.

wxwax

I practice this all the time. In fact, I've become histogram dependent and am currently seeking counseling to guide me back to meter use.

Anymore, I shoot, check the histogram and then make my adjustments, rather than metering and shooting. Yes, that makes me a bad person, weak in basic technical skiils. :uhoh

Sometimes, protecting the right side of the histogram isn't the best idea. It leads to underexposed shots. Sometimes it's a good idea to shoot a good exposure for your subject, and let some highlights blow out. The alternative is to rely on RAW to bail you out, which isn't a good practice. Or make multiple exposures, for which you need a tripod.

In other words, some shots will have blown out highlights, and that's OK. You just need to be able to decide when it's OK and when it's not.

Andy

One point to remember - the histo in the camera, is NOT the same as the RAW file histo - it's representation of the in-camera parms applied to the jpg. And so, if you're a RAW shooter, you'll want to understand the difference. For example, my histo can show plenty of what looks like blown highlights on the in-camera jpg histo, but I know that it's not so on the RAW histo. It's a feel thing.

wxwax

Andy wrote:

One point to remember - the histo in the camera, is NOT the same as the RAW file histo - it's representation of the in-camera parms applied to the jpg. And so, if you're a RAW shooter, you'll want to understand the difference. For example, my histo can show plenty of what looks like blown highlights on the in-camera jpg histo, but I know that it's not so on the RAW histo. It's a feel thing.

Good stuff, I seem to remember reading this before. Thanks for the reminder, not something I've thought much about. Must change that.

wxwax

One other thing worth mentioning. The 1DmkII has a nice histogram feature - it shows all three color channels.

The reason this matters is because you can badly over-expose one color channel and a "normal" histogram won't tell you know you're in trouble.

I've shot bands in crummy lighting that's heavy on red, for example. And while the combined histogram looks OK, in fact the red channel is trashed, beyond the ability of even RAW to come to the rescue.

So if you don't have a three-color histogram, pay careful attention when you're in special lighting situations.

DavidTO

pathfinder wrote:

Dave,
This is something that does not seem to be widely understood. Michael Reichman's article explains the reasons for exposing to the right - I can never remember the specific pixels and bits, but he explains it very clearly.

http://www.luminous-landscape.com/tutorials/expose-right.shtml

Most of the information in an image is in the first few steps in the histogram on the right. SO, yes I try to keep my histograms to the right, but short of blowing out the highlights of course.

Hedging to the left of the histogram is a sure way to increase the noise in your images.

Yeah, that's the article I linked in my first post.

I've been overprotecting my highlights, I think, being too conservative, figuring that RAW could make up the difference. Lazy, I guess is the word. I'm going to work harder to use the right when it makes sense to.