Exposure to the left or to the right?

alaios

https://www.youtube.com/watch?v=q3nmWD_Ld8s
6:32
this guy says that I should try to exposure to the left. Are my English that bad?

Regards
A

P.S Something is going on with the editor tonight.... and fonts look weird

pathfinder

The secret to using a histogram is exposing to the right - you want to retain detail in the brightest tones, AND you will capture the most detail in the darker tones when you expose to the right. BUT - you must not expose so far to the right that you begin to blow out a color channel. That is why my camera is set up to show me the histogram in its RGB form - that is three histogram bars, one each for red, green, and blue. It is not uncommon to fry one color channel and not see it with a standard luminosity histogram. That is why is suggests exposing to the left, which is not the best technique in most pros opinion.

If you expose to the left, like he is suggesting, you are building in more noise in your images, at the time of shooting. It is easy, and modern camera files will still look pretty good, but files exposed to the right will look better if done properly. Expose to the right, and you decrease the noise in the file, by using the exposure slider to darken the image at the time of RAW processing.

A good discussion of this topic is here - http://www.luminous-landscape.com/tutorials/expose-right.shtml

And here - http://www.luminous-landscape.com/tutorials/optimizing_exposure.shtml


I think your video link needs a Not Safe for Work label also, it might surprise some folks inadvertently.

arodney

He (fellow in the video) get's it mostly correct until he starts associating the camera histgram with the one in a raw converter. Then he's hopelessly lost! Certainly when referring to raw. The histogram on the camera is based on the JPEG NOT the raw data. And as such, recommending exposing to the left is incorrect! This article should help:

http://www.digitalphotopro.com/technique/camera-technique/exposing-for-raw.html
http://www.luminous-landscape.com/tutorials/expose-right.shtml

You simply can't treat ideal exposure for raw and JPEG the same way, especially when the camera Histogram doesn't provide any information about the raw data. It's a big fat lie!

You could under expose film and push it in the lab. Is that ideal, will it provide the best quality? No! As pathfinder states, under exposing raw data simply add's more noise in the shadows.

ETTR (Expose To The Right) is NOT about over exposing. it's about optimal exposure (for raw). As such, don't clip highlight data you wish to retain (in the raw or JPEG). This really is photography 101. While the video's first few minutes are useful in explaining to a novice what a Histogram is and shows, after that, this chap is confused and providing poor advise (so call him out).

alaios

arodney wrote: »

He (fellow in the video) get's it mostly correct until he starts associating the camera histgram with the one in a raw converter. Then he's hopelessly lost! Certainly when referring to raw. The histogram on the camera is based on the JPEG NOT the raw data. ....
You simply can't treat ideal exposure for raw and JPEG the same way, especially when the camera Histogram doesn't provide any information about the raw data. It's a big fat lie!
...

Hi thanks for your reply. Very interesting is also your position that the histograms have to do with jpegs. Is this the same with all the cameras?
Unfortunately my camera can not show live the color channels... What can I do to see if I blow out a color channel before taking the shot?

R
A

arodney

alaios wrote: »

Very interesting is also your position that the histograms have to do with jpegs. Is this the same with all the cameras?

The camera histogram represents the JPEG the camera will process. That histogram should match very closely what you see in Photoshop's histogram. The raw data histogram isn't shown to us. Thus, expecting the JPEG histogram to represent the actual raw data as the video host implies is absolutely not the case. IOW, if you capture raw data, exposing to the left is even WORSE in terms of more noise than capturing raw and basing that on the JPEG histogram. Expose to the Right implies move that incorrect JPEG histogram farther to the right (and that's an educated guess) so that the raw data is (more) properly exposed. Thus ETTR. It isn't about over exposing, it's about overcoming the big fat lie the camera histogram is providing about the raw data.

I've been toying with doing another video myth buster and doing one on histograms guess I'll have to do it.

arodney

arodney wrote: »

I've been toying with doing another video myth buster and doing one on histograms guess I'll have to do it.

And here it is:

Everything you thought you wanted to know about Histograms

Another exhaustive 40 minute video examining:

What are histograms. In Photoshop, ACR, Lightroom.
Histograms: clipping color and tones, color spaces and color gamut.
Histogram and Photoshop’s Level’s command.
Histograms don’t tell us our images are good (examples).
Misconceptions about histograms. How they lie.
Histograms and Expose To The Right (ETTR).
Are histograms useful and if so, how?

Low rez (YouTube): http://www.youtube.com/watch?v=EjPsP4HhHhE
High rez: http://digitaldog.net/files/Histogram_Video.mov