Evaluation of a Simple and Affordable Image-Based Procedure to Measure Particle Size Distribution

Abstract

The classical measurement method of particle size for sands and gravels is sieving, but in recent years, imaging methods have been shown to be more reliable. However, imaging procedures require specialized devices (such as Camsizer), proprietary software (such as Optgran-CS), dedicated illumination, or other issues. Furthermore, image resolution in digital cameras improves constantly over time, including in cameras in cellular phones, which leads to the idea that using a standard commercial device and a simple procedure could give results that could be accurate enough. In this work, we first define a simple way of finding the particle size distribution without using any special device, only with a commercial camera and a well-known free image-processing software. Once defined, we analyze the error magnitude and dispersion of the method with different samples and light intensities. To make the procedure even more accessible, the use of a smartphone camera is also studied. The results show that the method can be used taking into account a correction factor within a narrow interval, which makes this simple method also robust.