Pyrotechnics sputtered into life, their sodium light cutting through the fog.
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Its shiny skin glinted in the sodium light of the loading bay; its floor wasn't sticky; the seats didn't smell like fried chicken.
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Fesnels Biprism complete set up this means optical bench type set up consisting of Fresnels biprism double convex lens, sodium light source etc.
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The index of refraction was found by immersion to be 1.821±.001, using sodium light and adjusting for small temperature changes. Like so many calcium garnets, goldmanite was found to be weakly anisotropic. The cell edge of goldmanite is 12.011 Å, as determined by x-ray powder diffraction analysis.
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The pale yellow and red varieties have very little iron and are translucent. The darker, more opaque varieties contain more iron. Some specimens are also fluorescent in ultraviolet light. Bands of sphalerite The refractive index of sphalerite (as measured via sodium light, average wavelength 589.3 nm) is 2.37.
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A scattering of round-brilliant cut diamonds shows the many reflecting facets The luster of a diamond is described as 'adamantine', which simply means diamond-like. Reflections on a properly cut diamond's facets are undistorted, due to their flatness. The refractive index of diamond (as measured via sodium light, 589.3 nm) is 2.417. Because it is cubic in structure, diamond is also isotropic.
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There were two photography experiments. S-1 hoped to image the Zodiacal light during an EVA, but this was changed to inside the spacecraft after the problems encountered by Cernan. And S-11 involved the astronauts trying to image the Earth's airglow in the atomic oxygen and sodium light spectra. They took 44 pictures as part of this experiment with three being of actual airglow.
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A so-called "yellow screen" is accomplished with a white backdrop. Ordinary stage lighting is used in combination with a bright yellow sodium lamp. The sodium light falls almost entirely in a narrow frequency band, which can then be separated from the other light using a prism, and projected onto a separate but synchronized film carrier within the camera. This second film is high-contrast black and white, and is processed to produce the matte.
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Cinnabar is generally found in a massive, granular or earthy form and is bright scarlet to brick-red in color, though it occasionally occurs in crystals with a nonmetallic adamantine luster. It resembles quartz in its symmetry. It exhibits birefringence, and it has the second highest refractive index of any mineral. Its mean refractive index is 3.08 (sodium light wavelengths), versus the indices for diamond and the non- mineral gallium(III) arsenide (GaAs), which are 2.42 and 3.93, respectively.
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If the path lengths of the beams differ by a half-integral number of wavelengths (e.g., 0.5, 1.5, 2.5 ...), constructive interference will yield a strong signal. The results are opposite if a cube beam-splitter is used, because a cube beam-splitter makes no distinction between a front- and rear-surface reflection. Use of partially monochromatic light (yellow sodium light) during initial alignment enabled the researchers to locate the position of equal path length, more or less easily, before switching to white light.
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Double- slit fringes with sodium light illumination In the double-slit experiment, the two slits are illuminated by a single light beam. If the width of the slits is small enough (less than the wavelength of the light), the slits diffract the light into cylindrical waves. These two cylindrical wavefronts are superimposed, and the amplitude, and therefore the intensity, at any point in the combined wavefronts depends on both the magnitude and the phase of the two wavefronts.Born & Wolf, 1999, Figure 7.4 These fringes are often known as Young's fringes.
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Combination HPS/MH lights combine a metal halide and a high-pressure sodium in the same bulb, providing both red and blue spectrums in a single HID lamp. The combination of blue metal halide light and red high-pressure sodium light is an attempt to provide a very wide spectrum within a single lamp. This allows for a single bulb solution throughout the entire life cycle of the plant, from vegetative growth through flowering. There are potential tradeoffs for the convenience of a single bulb in terms of yield.
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Foremost is the refractive index (RI) of a diamond, which, at 2.417 (as measured by sodium light, 589.3 nm), is fairly high compared with that of most other gems. Diamond's RI is responsible for its brilliance—the amount of incident light reflected back to the viewer. Also important is a diamond's dispersive power—the ability of the material to split white light into its component spectral colors—which is also relatively high, at 0.044 (as measured from the B-G interval). The flashes of spectral colors—known as fire—are a function of this dispersion, but are, like brilliance, only apparent after cutting.
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Instead of adopting the usual blue moonlight or blue street lamp look, he used an orange sodium-light effect. The Coen brothers shot much of the film with wide-angle lens because, according to Joel, it made it easier to hold focus for a greater depth and it made camera movements more dynamic. To achieve the point-of-view of a rolling bowling ball the Coen brothers mounted a camera "on something like a barbecue spit", according to Ethan, and then dollied it along the lane. The challenge for them was figuring out the relative speeds of the forward motion and the rotating motion.
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Clinohumite's transparency ranges from transparent to translucent; its luster ranges from a dull vitreous to resinous. Its refractive index (as measured via sodium light, 589.3 nm) is as follows: α 1.631; β 1.638-1.647; γ 1.668;, with a maximum birefringence of 0.028 (biaxial positive). Under shortwave ultraviolet light, some clinohumite may fluoresce an orangy yellow; there is little to no response under longwave UV. The Taymyr material is reported to be a dark reddish brown while the Pamir material is a bright yellow to orange or brownish orange. The Pamir material also has a hardness slightly greater than 6, a lower specific gravity (3.18), and higher maximum birefringence (0.036).
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The refractive index of Canadian material (as measured via sodium light, 589.3 nm) is as follows: α 1.522; β 1.672–1.673; γ 1.676–1.679; biaxial negative. Under ultraviolet light, ammolite may fluoresce a mustard yellow. An iridescent opal-like play of color is shown in fine specimens, mostly in shades of green and red; all the spectral colors are possible, however. The iridescence is due to the microstructure of the aragonite: unlike most other gems, whose colors come from light absorption, the iridescent color of ammolite comes from interference with the light that rebounds from stacked layers of thin platelets that make up the aragonite.
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The lustre of turquoise is typically waxy to subvitreous, and its transparency is usually opaque, but may be semitranslucent in thin sections. Colour is as variable as the mineral's other properties, ranging from white to a powder blue to a sky blue, and from a blue-green to a yellowish green. The blue is attributed to idiochromatic copper while the green may be the result of either iron impurities (replacing aluminium) or dehydration. The refractive index of turquoise (as measured by sodium light, 589.3 nm) is approximately 1.61 or 1.62; this is a mean value seen as a single reading on a gemological refractometer, owing to the almost invariably polycrystalline nature of turquoise.
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Sodium light produces a fringe pattern that displays cycles of fuzziness and sharpness that repeat every several hundred fringes over a distance of approximately a millimeter. This pattern is due to the yellow sodium D line being actually a doublet, the individual lines of which have a limited coherence length. After aligning the interferometer to display the centermost portion of the sharpest set of fringes, the researcher would switch to white light. The mercury trough allowed the device to turn with close to zero friction, so that once having given the sandstone block a single push it would slowly rotate through the entire range of possible angles to the "aether wind," while measurements were continuously observed by looking through the eyepiece.
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Diamonds are usually cut into brilliants to bring out their brilliance (the amount of light reflected back to the viewer) and fire (the degree to which colorful prismatic flashes are seen). Both properties are strongly affected by the cut of the stone, but they are a function of diamond's high refractive index (RI—the degree to which incident light is bent upon entering the stone) of 2.417 (as measured by sodium light, 589.3 nm) and high dispersion (the degree to which white light is split into its spectral colors as it passes through the stone) of 0.044, as measured by the sodium B and G line interval. Thus, if a diamond simulant's RI and dispersion are too low, it will appear comparatively dull or "lifeless"; if the RI and dispersion are too high, the effect will be considered unreal or even tacky. Very few simulants have closely approximating RI and dispersion, and even the close simulants can be separated by an experienced observer.
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In Fig. 4a, the horizontal beam crosses the beam splitter three times, while the vertical beam crosses the beam splitter once. To equalize the dispersion, a so-called compensating plate identical to the substrate of the beam splitter may be inserted into the path of the vertical beam. In Fig. 4b, we see using a cube beam splitter already equalizes the pathlengths in glass. The requirement for dispersion equalization is eliminated by using extremely narrowband light from a laser. The extent of the fringes depends on the coherence length of the source. In Fig. 3b, the yellow sodium light used for the fringe illustration consists of a pair of closely spaced lines, D1 and D2, implying that the interference pattern will blur after several hundred fringes. Single longitudinal mode lasers are highly coherent and can produce high contrast interference with differential pathlengths of millions or even billions of wavelengths. On the other hand, using white (broadband) light, the central fringe is sharp, but away from the central fringe the fringes are colored and rapidly become indistinct to the eye.
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