Learning to See Stereoimages in 3D
Contents:
1) Using the Viewer
2) Stereo without the Viewer
3) Stereo pictures in Streitwieser, Heathcock & Kosower
4) Where to get Viewer

Most individuals can achieve binocular stereovision. (Some are physiologically incapable, for example because one eye is vastly dominant. To drive a car or play a sport they must depend on other depth clues from motion, shading, etc.). Stereopsis is a very useful skill in structural chemistry and biology, especially if you learn to do it without the help of a viewer.

Try your best with a viewer to see the textbook's stereo figures in glorious three dimensions. To succeed you will need to do two things:

Bend the viewer about the red pivot to accommodate separation between your eyes and between the images.
(Note; it is almost impossible to bend the viewer if you're squeezing it tightly. Hold it gently with both hands with your little fingers crooked under the front a little. Use your little fingers to spread the viewer and your palms to compress it.)

Rotate the book on the table (or your head about an axis perpendicular to the page) in order to get the two images to be the same height and superimpose.

Watch the page as you make these two adjustments. Bending displaces the two images right and left, the second displaces them up and down on the page. Use these two relative motions to steer a pair of corresponding atoms into coincidence. (It may help to color the two atoms that you are trying to steer red. You might try Figure 2.14a on page 27 and color the top atom red in each view.) When they coalesce, you often see three frames with the center image, seen by both eyes, in stereo.

If you are successful with the viewer, you can almost certainly succeed without the viewer. The trick is to make your eyes point in directions that they haven't done simultaneously since you learned to coordinate them in infancy. The right eye must be fixed on the right image, when the left eye is fixed on the left (this is what you did previously by pivoting the stereo viewer). It's best to try first when you are tired, and to pretend that you're looking at something far away, when in fact your nose is touching the page between the two stereo images. By putting your nose so close to the page, you make it impossible for both eyes to look at the same image. (You won't succeed by being self-conscious.)

If the pictures are too far apart, you can fold a pleat in the page to bring them closer together. (You could try with Figure 2.14 being careful to keep the two images parallel.)

Concentrate on a pair of corresponding atoms in the two images (again coloring them helps). They will look fuzzy because your eyes can't focus on the page when your nose is touching it. Once you have steered the pair into superposition by rotating the book about the axis perpendicualr to the page, slowly pull the book away, while maintaining your concentration on the coalesced atom. Once your eyes can focus and you see that atom clearly, start looking around at its neighbors. It will feel uncomfortable at first, and you will lose the "lock" many times, but ultimately you will probably learn to see the third dimension without a viewer. I guarantee that you will like this.

An oculist assured me that this will not damage your eyes.

You can practice with stereo figures on the following pages of Streitwieser and Heathcock
(Red means especially fun):

page

Figure

Subject

page

Figure

Subject

25

2.10b

sp hybrid

26

2.13

sp3 hybrid

27

2.14a

methane

76

5.2

anti butane

77

5.4

ethane

80

5.1

butane conformers

81

5.11

pentane conformers

90

5.14a

cyclopropane

91

5.1a

cyclobutane

92

5.18a

cyclohexane

93

5.22

cyclohexane ring flip

107

6.4

Cl attacks CH4

109

6.8

CH3 attacks Cl2

124

7.2

2-iodobutane enantiomers

130

7.6

S and R stereocenters

144

7.14b

boat cyclohexane

177

9.2

SN2 displacement

654

22.9a

cyclooctatetraene

914

28.1

b-D-glucose

934

28.2a,b

b-Cellobiose & Sucrose vibration

966

25.9

GFG tripeptide

991

29.13

Protein a-helix

995

29.18

Myoglobin

1163

33.1

B-DNA

Essay 6 (7 and 5 pages after 621 in text) A phosphonate drug candidate and its "docking"

For an additional thrill try looking at a stereo presentation by Chem3D Viewer. This allows both motion and 3D. Who could ask for anything more?

Custodians of Stereoviewers
Three class members have volunteered to be custodians of the plastic stereoviewers.  You may contact them to arrange for using one and getting some advice on their use.   Click here for their names and phone numbers.

Sometimes the little mirrors pop out. Don't panic, just try not to drop or break them and bring them to class for repair.