Essential Skill to Master for Image Quality— An
ETTR (Expose to the Right) is a concept alluded to and discussed briefly A CALL TO ACTION: Build Intelligent ETTR Into Digital Cameras.
Recent email tells me that the ETTR concept is still not clear to some readers of this blog— I direct those readers to the ETTR section of DAP.
ETTR could be stated more simply as the double entendre Expose Right:
- Expose “right” (meaning correctly) meaning the maximum exposure the sensor can handle without losing detail.
- Expose “right” meaning that the histogram should be pushed to the right side (very bright), but no more than the sensor can handle without losing detail.
At present, ETTR presumes the use of RAW format (not JPEG), but that is only because of camera exposure modes implemented by thinking “inside the film box”.
As sensors get better and better, the value of ETTR remains: smaller and denser sensors mean that ETTR can deliver near-DSLR quality in much smaller sensors, witness the Sony RX100, Sigma DP Merrill, Olympus OM-D E-M5 (and others).
Part of my reason for writing so heavily on this is for public “prior art” so no camera manufacture can screw the industry by patenting ETTR, claiming “new and non obvious”. I certainly think it is obvious, but patent examiners often grant ridiculous claims.
I have been using ETTR ad-hoc for some years now. But it is only the past few months that I have intensively researched it across cameras and brands with the result that I now must conclude my error in significantly underestimating the amount of improvement possible. That is why my recent coverage has been focused so strongly in this area.
ETTR is a must-master digital skill
ETTR cannot be applied in every photographic situation, but it applies to most. ETTR is a technical skill; it is not about creativity. Both are required to be a strong photographer.
ETTR is the single most important thing you can do for image quality with any digital camera besides Making a Sharp Image. Especially with small sensor cameras, ETTR makes images sharper by reducing noise that obscures fine image detail.
How well well ETTR works and why ETTR works take some explaining, and this is presented in general in the ETTR section of DAP, along with all the other camera-specific research presented over the past six weeks or so.
Was black and white film the original ETTR?
Not using ETTR is like a black and white photographer having no knowledge of how to push/pull film or paper in development— which in the heyday of black and white film would fairly have been said to be incompetence.
Was Ansel Adams in essence an ETTR master with black and white? Because the resulting density of the negative relied on exposure together with the type of developer, duration of development, temperature, and method of agitation, all of which alter the tonal range and contrast of the resulting negative. ETTR with digital is thus an eminently appropriate photographic approach, but one that can and should be automated by the camera.
Kit L writes:
This would end so many problems with digital. And I agree 100% re. ETTR histogram; I have been experimenting with the DP2 M, and often dial in +0.7 EV, and I might try more. I have to say that I find the UI truly intelligent, too.
DIGLLOYD: I often see up to 1.7 stops with the Sigma DP Merrill cameras. It all depends on the lighting (mainly). So far +1 to +1.7 seems to be a consistent winner.
I have heard from a reader that the new BlackMagic video camera has an auto-ETTR feature when recording starts. If so, it means someone out there is not as clueless as Nikon and Canon and Sony and Olympus and Sigma and Leica. Sigh.