Have you ever walked into a business, glanced down at the dull and scuffed floor where the only thing reflected is a lack of attentiveness, and thought, man, these people really care about what they’re doing? Of course not. Because if a business doesn’t take pride in the first thing a customer sees, what’s literally right beneath their feet, then how serious can that business truly be? On the other hand, if that same person steps onto a properly polished concrete floor that reflects the wonderful world around them in precise, clear imagery, their initial impression might be quite different. And what is the technical term to define the sharpness of all those surface reflections? That would be Distinctness of Image, or DOI.

As a matter of fact, DOI has now emerged as the crème de la crème of measurements when it comes to judging overall floor appearance. This rise to prominence all began with a pesky visual flaw known as “orange peel,” where the surface reflections resemble the bumpy skin of an orange. The thing about orange peel is that gloss readings don’t catch it. As a result, two floors, one with orange peel and one without, which look completely different, can have the exact same gloss readings as long as the surface is equally shiny. Orange peel can’t escape a meter that can calculate DOI, however, as the distorted reflection would be as obvious to such an instrument as it would be to the human eye.



Orange Peel Effect

The DOI scale ranges from 1-100, with 100 indicating a surface that reflects a perfect, undistorted image. This is the ever-elusive goal. To take a DOI reading, the meter uses a smaller measurement angle at 20°, as it provides a higher resolution. Combined with a haze reading of less than 10 haze units (HU), DOI is also an integral component to a Reflected Image Quality (RIQ) assessment, which is an overall indicator of surface quality.

But all acronyms aside, what does this mean to you, as an enthusiastic member of the surface prep community? That one is easy. As prevalent and useful as a gloss reading may be, it is not the only fish in the sea. As a matter of fact, with all the recent meter advances, gloss alone is only about midway up the food chain. If you are looking for an apex predator when it comes to hunting down flaws in polished concrete, DOI is a very dangerous beast. Think of it as the Great White of the Surface Prep Ocean. And if you want to measure Distinctness of Image both effectively and efficiently, you’re going to need a robust system like Runyon Data Services, which can take advantage of such a formidable weapon.