Goethe’s Colour Spectra.

Yesterday, 7th November 2014 I was searching Google Images for suitable photographic images to add into my post “Williams’ Pin Prism, and Fraunhofer Lines.”. This was not an easy task because most images do not show the true visual evidence and are more computer graphics than reality. However, the task was definitely worthwhile, because I came across an image originally produced by  Johann Wolfgang von Goethe. (1749 – 1832)

Most modern images are similar to the ones below.

These images are totally against the reality of what happens with prism spectra, and I find it very annoying , especially when being used to teach people.

Note; I have been sent this video clip from a reader who asked me to explain it.

http://www.youtube.com/watch?v=7Fl0GZsBhGo&NR=1

I am afraid that the contents of it demonstrate the poor teaching and lack of honesty in modern physics.

The drawings below, originally created by Goethe. and re-created by www.handprint.com are very close to the actual/true situation. His method/style used is identical to that used by myself, so he definitely beat me to it.

handprint : goethe’s “zur farbenlehre” www.handprint.com380 × 555Search by image

“light” and “dark” spectral mixtures from. Goethe’s “primordial” fringes adapted from Plate IV, Figures 1 and 2 and ¶214-¶216 of Zur Farbenlehre (1810)

 I assume that the above colours are based on the actual colours seen in the original book, which will have faded. In the top picture the Green shown should be a very bright Green.

The lighter Blue should be Cyan.

Where the question mark is, this area should be a dark Green.

The top picture (“Light” spectrum) is what I refer to as an “Expansion Spectrum”.

The bottom picture (Dark” spectrum) is what I refer to as a “Compression Spectrum”.

In this picture, where the question mark is, this area should actually be very pale Mauve or White. “Purpur” should actually be Magenta. Magenta only occurs in compression spectra and Greens only occur in expansion spectra.

Note; It is the slit, (that constricts the light into a beam), that actually creates the colours.  The White beam entering the prism has thin Yellow + Red + Blue edges to it. This is why the colours start at edge of the spectra exiting the prism, as shown in the above drawings. What is missing from the top drawing is the dark Blue band. Its energy is measurable  and is named “Infra Red”  due to lack of knowledge, by the physicists. It is missed because this ‘true’ spectra Blue is very dark and is ‘lost’ against the dark background. The lighter Blues are a mixture of either Blue and White or Blue and Red.

In the drawing below, the left hand side (White) is the source of the light. This light passes through an aperture (Slit) and shines onto the prism.

In passing through aperture, narrow coloured edges are created on each side of the beam of light. These edges are composed of three colour bands, Blue on the outer edge, Red in the middle and Yellow on the inside  These edges are created by the Laws of Fluid Mechanics. If you look under “Orifices” in your text book on Fluid Mechanics, all should be explained.

See also  my “Taper Slit Experiment” and my “Taper Silhouette  Experiment.

Author – Brian Williams