Which types of 3D glasses can be used?
There're many different way to create a 3D illusion. Depending of the method you may need a certain type of 3D glasses. The so called Anaglyph glasses will work with RedGreen these glasses are available in red-green, red-blue or red-cyan. The so called Pulfrich glasses can not be used with RedGreen. The Pulfrich glasses do only work with moving images (that means film and video) but won't work with still images.

Where can I get these 3D glasses?
Here's a short list of shops for 3D glasses (please let me know if I should add another one here):
  • In Germany you can get 3D glasses at Perspektrum. A very cheap and simple way to buy just one or two paper 3D glasses.
  • In the US you can buy 3D glasses at berezin.com. They ship worldwide.
  • There are many other online shops where you can get 3D glasses. Search for "3D glasses" at google.com

What's the reason for ghost images?
If you look at a 3D image through the 3D glasses you may see ghost images. That means parts of the image which should be only visible with one eye is also visible with the other eye. This will happen when the colors that are displayed on the screen do not completely match the colors which can pass the red and green filters of the 3D glasses. Sometimes this is caused by the monitor itself which doesn't show neutral colors (especially displays of older Notebook computers do not have a good color quality, but also the current iBooks and PowerBooks do not have really good displays). Also the monitor must be set to thousands or millions of colors.

When saving 3D images as JPEG I'll get ghost images
JPEG is not a lossless image file format. Some information and details are removed from the image when saved. Often this will be hardly visible for normal images, but for 3D images this information loss can make an image worthless. So when saving a 3D image you should use a lossless image file format like PICT, PNG or TIFF.

Also when manipulating the 3D images later with an image processing application you should be very careful not to change the colors.

What's the difference between red-green, red-blue and rot-cyan 3D glasses?
Red-green and red-blue 3D glasses let only pass two of the three color components (red, green, blue) to the eyes. Therefore you can't get a realistic color impression of the image (one color component is completely filtered out), all you see is some kind of monochrome image. Red-cyan 3D glasses let pass all three color components to the eyes (green and blue light can pass the cyan filter). Though the color components will be seen by different eyes, you can get a realistic color impression of the image.

In RedGreen you can create monochrome and color 3D images. Both images can be viewed with the three kinds of 3D glasses (red-green, red-blue and red-cyan). But only with red-cyan glasses you can profit from color images (with red-green and red-blue glasses you'll only get a monochrome impression of color images). But in some cases you may get better results when creating monochrome 3D images even when using red-cyan 3D glasses. This can happen if certain details of the original image will result in a very different brightness in the resulting 3D image for the left and right eye. This can be irritating. Creating monochrome 3D images will always result in a well balanced brightness for the left and right eye. When only using red-green or red-blue 3D glasses you should always create monochrome images to make sure that you'll always get a balanced brightness for both eyes.