Using a TAPPI chart is essential for examining the size and dimensions of microscopic spots. Also known as the TAPPI Dirt Estimation Chart, it contains a list of different-size spots. Each spot ranges in size from 0.02 to 5.00mm. The TAPPI chart is used in conjunction with digital software to complete size measurements. Although the chart is suitable for determining the square millimeter size of a speck of dirt, it is not designed for examining spots created from other substances, such as blood.
Load the TAPPI transparent chart software onto your computer. Purchase the software from the TAPPI organization by calling: 1-800-332-8686.
Attach a mechanical ocular adapter to the eyepiece of a 100-power magnifier microscope. Attach a digital camera able to capture photos up to 1600-by-1200 pixels per inch (PPI) to the adapter. Follow adapter instructions for connections to the microscope and the camera.
Insert the microscope slide containing the dirt specks onto the microscope stage. Adjust the light aperture and focus via TAPPI chart instructions. Take a picture of the spec with the camera to create a photomicrograph. Save the photomicrographic image as a GIF or JPEG file onto the camera's memory card.
Upload the image from the memory card onto the computer. Open the image in the TAPPI software. Follow prefabricated software instructions to analyze and process the photomicrograph to determine a size in accordance with the digital TAPPI chart.