This interactive tutorial illustrates the effects of various types of noise which may be superimposed on images. In some examples below, the amount of speckle noise has been increased to relatively high levels to make it readily visible, but operating a camera at high gain (e.g., dim light) can produce this amount. Likewise the amount of shot noise can be made very high and most cameras would be rejected by the manufacturer if there were more than a few defective pixels of this type, but some kinds of microscopy can produce “dropouts” which are the same as shot noise, and dust on negatives also produces the same effects.

The tutorial initializes with a randomly selected specimen appearing in the Specimen Image window. The Choose A Specimen pull-down menu provides a selection of specimen images, in addition to the initial randomly chosen one. The radio buttons select different types of noise, which may arise from various causes.

---

BACK TO INTRODUCTION TO DIGITAL IMAGE PROCESSING AND ANALYSIS

BACK TO MICROSCOPY PRIMER HOME

Questions or comments? Send us an email.

© 1998-2009 by Michael W. Davidson, John Russ, Olympus America Inc., and The Florida State University. All Rights Reserved. No images, graphics, scripts, or applets may be reproduced or used in any manner without permission from the copyright holders. Use of this website means you agree to all of the Legal Terms and Conditions set forth by the owners.

This website is maintained by our
Graphics & Web Programming Team
in collaboration with Optical Microscopy at the
National High Magnetic Field Laboratory.

Last modification: Thursday, Feb 25, 2016 at 10:48 AM

Access Count Since July 20, 2006: 6876

For more information on microscope manufacturers,
use the buttons below to navigate to their websites: