Microscopy Primer
Light and Color
Microscope Basics
Special Techniques
Digital Imaging
Confocal Microscopy
Live-Cell Imaging
Photomicrography
Microscopy Museum
Virtual Microscopy
Fluorescence
Web Resources
License Info
Image Use
Custom Photos
Partners
Site Info
Contact Us
Publications
Home

The Galleries:

Photo Gallery
Silicon Zoo
Pharmaceuticals
Chip Shots
Phytochemicals
DNA Gallery
Microscapes
Vitamins
Amino Acids
Birthstones
Religion Collection
Pesticides
BeerShots
Cocktail Collection
Screen Savers
Win Wallpaper
Mac Wallpaper
Movie Gallery

Interactive Java Tutorials

Color Filters

Examine how color filters operate to alter the apparent color of objects visualized under white light and monochromatic illumination. The tutorial enables visitors to drag and drop red, green, and blue virtual color filters over objects illuminated with either white light or light that has been previously filtered with one of the primary additive colors.

Interactive Java Tutorial
ATTENTION
Our servers have detected that your web browser does not have the Java Virtual Machine installed or it is not functioning properly. Please install this software in order to view our interactive Java tutorials. You may download the necessary software by clicking on the "Get It Now" button below.

 

The tutorial initializes with a series of photographs contains images of a playing card (the 3 of hearts), a green bell pepper, and a cluster of bluish-purple grapes superimposed on a black background. Beneath the photographs are filled circles representing red, green, and blue filters. In the photograph on the far left, the three objects are illuminated with white light and appear as we expect to see them under natural lighting. In the second photograph, the objects are illuminated with red light. Note that the playing card is reflecting all of the red light that strikes it, while only the grape stem and white highlights on the grapes and pepper reflect red light. The majority of red light striking the grapes and pepper is being absorbed.

The third photograph of the series presents the objects under illumination with green light. The symbols on the playing card are now black and the body of the card is reflecting green light. The grapes are reflecting some green light, while the pepper appears normal (but with green highlights). The fourth photograph (on the far right) illustrates the objects under blue illumination. The grape cluster appears normal with blue highlights, but the stem has turned black and is now invisible. The playing card is reflecting blue light with black symbols and the pepper is reflecting blue light only on the highlights. This series of images demonstrates how an object that looks red (for example, in white light) absorbs blue and green wavelengths, but reflects wavelengths in the red region of the spectrum. Therefore the object is seen as red.

Each of the effects produced by illuminating the objects in the photographs with filtered light can be verified by dragging the colored circles over the left-hand photograph and observing the effects. For example, drag the blue filter and place it over the photograph to see it change into the blue-filtered image as seen on the far right. When the blue filter is dragged over an image that already has been filtered with red light, the image turns black because the blue filter passes only blue light, which was removed by the red filter. Likewise, when the green filter is placed over the photograph that was filtered with blue light, the result is a black image. Alternatively, when the red filter is placed over the image already filtered with red light, no change occurs.

Contributing Authors

Matthew J. Parry-Hill, Robert T. Sutter and Michael W. Davidson - National High Magnetic Field Laboratory, 1800 East Paul Dirac Dr., The Florida State University, Tallahassee, Florida, 32310.


BACK TO PRIMARY COLORS

Questions or comments? Send us an email.
© 1998-2013 by Michael W. Davidson 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: Wednesday, Mar 26, 2014 at 02:24 PM
Access Count Since July 4, 1998: 175471
For more information on microscope manufacturers,
use the buttons below to navigate to their websites: