Another Good Reason to Expose to the Right

Original 9 ft. wide portion of Route 66 near Miami, Oklahoma
It is nicknamed "The Sidewalk" (click to enlarge)

Often we hear the recommendation to "expose to the right."  If you don't know what that means, I wrote about it in a previous blog post that you can find here.  Briefly, the reason to place your exposure as far to the right on your histogram without blowing out your highlights is because most of the image data recorded by your sensor is in the brightest two to three f/stops of light.  That is also why you get digital noise in your shadows, especially if you try to lighten them.  There is almost not image information in the dark areas of your exposure. So, making your exposure as bright as it can be, again without blowing out any highlights, then slightly darkening your image to taste in your image editing software will produce technically better image.  Aesthetics are another issue.

There are reasons for exposing for the center of your histogram, however.  If you are taking photographs using the JPEG format and have no intention of editing them later, or have to send them off to someone immediately without being able to edit them, then make an exposure that is as close as you can to reflect the scene.  You don't want to expose to the right, in this circumstance, and have all your images look over exposed.  But, I digress.

So what is the additional reason for exposing to the right?  Fixing vignetting (shading) caused by your lens.

We love to buy and use very fast lenses, such as lenses with an f/1.4, f/1.2 or even faster, apertures.  But, using these lenses wide open, which is the reason for buying them, causes vignetting in the corners. Eliminating the darkening of the corners when using an exposure that is on the dark side or even a correct looking exposure, can introduce digital noise when trying to lighten those shaded corners in your editing software.  If you expose to the right, you will still have to lighten the corners in relation to the rest of the frame, but you will minimize introducing any digital noise.  As I stated above, most of your image information in your file is in the brightest 2 to 3 f/stops.  So if the vignetted area is lighter rather than darker, then there is more information available and less digital noise.  Make sense?

In all practicality, are today's sensors so good that it really doesn't matter anymore?  Maybe.  But if you are a perfectionist, buy only the best gear and work very hard for the absolute best image, it may make a difference.  Try it and see.

Thanks for looking.  Enjoy!

Dennis Mook

Many of my images can be found at www.dennismook.com.  Please pay it a visit.  I add new images regularly.  Thank you.


All content on this blog is © 2014 Dennis A. Mook.  All Rights Reserved.  Feel free to point to this blog from your website with full attribution.  Permission may be granted for commercial use.  Please contact Mr. Mook to discuss permission to reproduce the blog posts and/or image.