The Flickr Interferencecolours Image Generatr

To all of you, a happy, healthy, harmonic, colourful, dynamic .... and peaceful New Year!

Ich wünschen Euch ein frohes, gesundes, harmonisches, farbenfrohes, dynamisches ..... und friedvolles Neues Jahr!

Til jer alle et glædeligt, sundt, harmonisk, farverigt, dynamisk ..... og fredfyldt nytår!

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After 32 years I did it again, and I had a lot of fun and was totally fascinated, as I was in 1992:

Interference colours of a soap film, January 2024

A few similar slides from 1992 in my album www.flickr.com/photos/99927961@N06/albums/72177720322895659/
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Nach 32 Jahren habe ich es noch einmal gemacht, hatte viel Spaß dabei und war genauso fasziniert wie 1992:

Interferenz-Farben einer Seifenhaut, Januar 2024

Ein paar ähnliche Dias von 1992 in meinem Album www.flickr.com/photos/99927961@N06/albums/72177720322895659/

As at the end of last year, I am showing a few digitized slides again:

A bursting soap bubble, February 1992.

Exposure time (= flash duration): 50 µs = 1/20.000 s

Digitized slide from 1992, the EXIF data refer to the camera used for digitizing, not to the original slide.

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Wie schon zum Ende letzten Jahres, zeige ich wieder ein paar digitalisierte Dias:

Eine platzende Seifenblase, Februar 1992

Belichtungszeit (= Blitzdauer): 50 µs = 1/20.000 s

Digitalisiertes Dia von 1992, die EXIF-Daten beziehen sich auf die Digitalisierung, nicht auf das Originaldia.

Tiny fly (~2mm)
Every species has its own a unique wing-structure

Mitutoyo 10x NA 0.28, tube lens: Raynox 125mm
Illumination: Oblique and dark field

Trichocera hiemalis
At temeratures around 0°C (32F) there is almost no activity from insects. This is an exception: protected by something similar to glycerol, they are even frost-resistant.

If the sun comes out only a little bit, they form dancing, loose swarms.


Mitutoyo 5x NA 0.14, tube lens: Thorlabs (165mm)
Illumination: Oblique
(Pano)

The tip of the forewing of Heteroptera is fairly thick (~1.2 microns), thus there is no color iridescence visible (brown curve). The base is even thicker and leathary. This is the origin of the name "hemiptera" which means "half-winged". The newer name Heteroptera means also "mixed-wings". This leads to the typical "X" structure of the closed wings in dorsal view, which is an easy means to identify "true" bugs.

Hind wings in contrast, are much thinner (~0.2 microns here), which leads to a brillant blue-violett if illuminated coaxially.

Forewings are shown here

Hind wings

Portrait of the bug

Small "true" bug, about 4-5mm

The tip of the forewing of Heteroptera is fairly thick (~1.2 microns), thus there is no color iridescence visible (brown curve). The base is even thicker and leathary. This is the origin of the name "hemiptera" which means "half-winged". The newer name Heteroptera means also "mixed-wings". This leads to the typical "X" structure of the closed wings in dorsal view, which is an easy means to identify "true" bugs.

Hind wings in contrast, are much thinner (~0.2 microns here), which leads to a brillant blue-violett if illuminated coaxially.

Forewings are shown here

Hind wings

Wing-thickness- analysis goes here


Mitutoyo M Plan Apo 7.5x NA 0.21 tube lens: Thorlabs 165mm
Illumination: Dark field, oblique and UV 365nm (UVIVF, just the eyes show fluorescence)

Hind wings are very thin, about half the wavelength of blue light!

The tip of the forewing of Heteroptera is fairly thick (~1.2 microns), thus there is no color iridescence visible (brown curve). The base is even thicker and leathary. This is the origin of the name "hemiptera" which means "half-winged". The newer name Heteroptera means also "mixed-wings". This leads to the typical "X" structure of the closed wings in dorsal view, which is an easy means to identify "true" bugs.

Hind wings in contrast, are much thinner (~0.2 microns here), which leads to a brillant blue-violett if illuminated coaxially.

Forewings are shown here

Portrait of the bug

Wing-thickness- analysis goes here


Mitutoyo M Plan Apo 20x NA 0.42 tube lens:Raynox 125mm
Illumination: Coaxial

Culiseta annulata (wing)

Mitutoyo 20x NA 0.42, tube lens: 165mm (Thorlabs)
Illumination: Oblique, diffused

Mitutoyo 7.5x NA 0.21, tube lens: 165mm (Thorlbs)
Illumination: Dark field and oblique

Cercopis vulnerata [Blutzikade]

The hind wings are rather thick (around 1 micron), so there are only faint green/ magenta interference colors visible.
Here some UV fluorescence is used to enhance the eyes.
If you don't like this, here is a picture with no UV enhancement
A reflection spectrum of the hind wings is shown here.

Mitutoyo M Plan Apo 5x NA 0.14 tube lens: Raynox 125mm
Illumination: Oblique and dark field.
Pano from 2 stacks.

Cercopis vulnerata [Blutzikade]

The hind wings of this insect are rather thick (almost 1 micron), so there are only faint green/ magenta interference colors visible.
The reflectance spectrum shows several "wiggles" (the more, the thicker is the film. Thus, the wings appear almost neutral grey.

A picture of the insect is shown here

Cercopis vulnerata [Blutzikade]

The hind wings are rather thick (around 1 micron), so there are only faint green/ magenta interference colors visible.

A reflection spectrum of the hind wings is shown here.

Mitutoyo M Plan Apo 5x NA 0.14 tube lens: Raynox 125mm
Illumination: Oblique and dark field
Pano from 2 stacks.

Bark louse, Psocoptera (Graphopsocus cruciatus), very widespread in Europe. The thin wings show interference colours (like soap bubbles).

Image height < 3mm

Mitutoyo M Plan Apo 5x NA 0.14 tube lens: Raynox 125mm
Illumination: Oblique and dark field

The wings of this parasitoid wasp shows various thickness zones, resulting in nice series of colours.

A detailed analysis is given here.


Mitutoyo 20x NA 0.42, tube lens165mm (Thorlabs)
Illumination: directed white

Portrait of this wasp is shown here

Looking close... on fridays
multicoloured abstract

The discussion below refers to the following foto:
Wing of parasitoid wasp
Portrait of this wasp is shown here

Upper figure: 3 examples of reflection spectra.
White: The thickest part of the wing (gray) shows so many wiggles in the spectrum, that it appeares neutral grey for the eye (center part of the wing). Thickness (almost) 1.5 Microns
Green: somewhere in between, thickness 631 nm (which corresponds to one wavelength of visible (green) light. Note that there are several green regions, cf. discussion below.
Blue: Light blue at the very bottom of the smaller wing. This is the thinnest region, with only 260nm thickness.

Lower figure: From this (simulated) "wing" you can see, that the mapping color->thickness is not unique. Especially with growing thickness, green and magenta regions appeare periodically (albeit with vanishing saturation, as thickness increases). This effect can be seen nicely in the real wing (upper wing, start from right to left)


The analysis was made with the following optics:
Mitutoyo M Plan Apo 100x NA 0.70 tube lens: Thorlabs 165mm
Illumination: white coaxial lightning

Psocoptera (Graphopsocus cruciatus), very widespread in Europe. The thin wings show interference colours (like soap bubbles).

Mitutoyo M Plan Apo 7.5x NA 0.121 tube lens: Thorlabs 165mm
Illumination: Oblique and dark field

Guess, whos blood this is...

Mitutoyo 5x NA 0.14, tube lense 125mm (Raynox)
Illumination: Dark field and oblique

Feather of a male duck

Mitutoyo 50x NA 0.55 tube lense 125mm (Raynox)
Illumination: Oblique diffused

Green aphid (wing) (Aphidoidea sp.)

Mitutoyo 50x NA 0.55, tube lens ITL200 (Nikon)

The wings of aphids are rather thin (about 500nm), and also very rough (+-160nm). Thats why they show up with rather small regions of the same color (in epi-illumination at high magnification).

Small midge with backlight interference colours

This is a unusual perspective for stacking: from the head to the back of the wings more than 2000 single shots were needed. Also the shape of the wings is somewhat strange from this view-point and the resulting projection. Colours are from BACKLIGHT thin-film interference.

Mitutoyo 10x, NA0.28, tube lens: 125mm (Raynox)
Illumination: Dark-field and oblique