Achromat Objective
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 Nikon 10X CFN Plan Achromat Phase 1 Microscope Objective  US $750.00
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 Swift Microscope w 5 Plan Achromat Objectives US $719.99
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 ZEISS 462046 MICROSCOPE OBJECTIVE ACHROMAT 46 20 46 US $635.00 |
 LOMO LUMAM Plan Achromat 40x Microscope Objective OB LPA40NCG US $334.99
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 Zeiss Centerable Pol Z 63 Achromat Objective US $333.00
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 5 LOMO Achromat objective 11 95x microscope Zeiss 190 US $320.00
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 Zeiss CP ACHROMAT 100x 125 Oil ∞ 017 Objective US $225.00
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 Zeiss CP ACHROMAT 40x 065 ∞ 017 Objective US $225.00
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 UNICO 40X Infinity Plan Achromat Objective NA 065 Microscope Accessories US $219.99
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 LOMO Achromat objective 85x 10 Water I with correct ring microscope Zeiss US $199.00
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 LOMO Achromat objective 60x 115 Lum C microscope Zeiss US $199.00
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 Objective Plan Achromat 100x 1255 US $195.00
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 Reichert USA Achromat 100 125 objective lens US $150.00
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 Objective Plan Achromat 10x 025 for Primo Vert US $150.00
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 Achromat lens 90x 06 125 Iris Oil microscope objective US $149.00
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 Achromat objective lens 11x 04 POLAR microscope LOMO US $149.00
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 AO Reichert 100X ∞ Corrected Achromat Oil Objective US $145.00
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 Meiji S Plan Achromat 50X oil Microscope objective US $159.00
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 Objective Plan Achromat 40x 065 for Primo Vert US $125.00
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 Achromat lens 90x06 125 Iris Oil microscope objective US $119.00
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 Achromat objective 100x 125 Oil POLAR microscope LOMO US $119.00
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 AO SPENCER MICROSCOPE OBJECTIVES LENS ACHROMAT OIL 100 125 MC FREE SHIPPING US $75.00
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 Achromat objective 25x 050 microscope LOMO US $69.00
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 Nikon CF Achromat 10x 025NA Objective US $61.00
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 Achromat objective lens 21x 040 POLAR microscope LOMO US $59.00
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 LOMO Achromat objective 40x 065 D0 microscope Zeiss US $59.00
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 LOMO 3 achromat 8x 40x 90x objective microscope US $55.00
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 LOMO 3 achromat 8x 40x 90x objective microscope 2 US $55.00
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 AO American Optical 45X 066 ∞ achromat microscope objective US $50.00
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 Melles Griot 04 OAS 010 Achromat 10 025 Objective US $49.95
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 PZO Achromat objective 20x 040 microscope BIOLAR Zeiss US $49.00
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 LOMO Epi Achromat objective F 82 037 microscope 27mm US $49.00
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 LOMO Epi Achromat objective F 139 030 microscope 27mm US $49.00
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 Achromat objective lens 47x 01 POLAR microscope LOMO US $49.00
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 BYLAN Achromat objective lens 4x 012 microscope BeLOMO US $49.00
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 LOMO Achromat objective 40x Lumin microscope Zeiss US $49.00
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 LOMO Epi objective achromat 95x 10 Oil microscope M27 US $49.00
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 LOMO Epi objective achromat F10 040 microscope M27 US $49.00
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 LOMO Achromat objective 40x 065 microscope Zeiss US $49.00
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 LOMO Epi Achromat objective F 62 065 microscope 27mm US $39.00
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 HbS ACHROMAT objective 10x 025 microscope Zeiss US $39.00
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 Achromat objective lens 9x 020 POLAR microscope LOMO US $39.00
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 Achromat objective lens 11x 025 POLAR microscope LOMO US $39.00
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 LOMO Achromat Epi objective F63 065 microscope M27 US $39.00
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 ACHROMAT objective 4x 015 microscope STEINDORF BERLIN US $39.00
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 ACHROMAT objective 45x 06 microscope STEINDORF BERLIN US $39.00
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 ACHROMAT objective 10x 03 microscope STEINDORF BERLIN US $39.00
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 BYLAN Achromat objective lens 10x 02 microscope BeLOMO US $39.00
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 Achromat objective lens 21x 04 POLAR microscope LOMO US $39.00
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 PZO Achromat objective 5x 012 microscope BIOLAR Zeiss LOMO US $39.00
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 Achromat objective lens 20x 04 POLAR microscope LOMO US $29.00
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 Achromat objective lens 9x 02 POLAR microscope LOMO US $29.00
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 Achromat objective lens 3x POLAR microscope LOMO US $29.00
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 CARL ZEISS ZEISS MICROSCOPE 10X 022NA ACHROMAT OBJECTIVE US $23.71
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Make Telescopes: Understand Amateur Telescopes
In the past there has been considerable discussion by those who make telescopes on the relative merits of reflector and refractor. From the standpoint of professional astronomers, there is no serious competition between them, as each type supplements the other in a well-rounded observing program. Let us first look at some of the optical characteristics of reflectors and refractors,
Very early in the 19th century, when advocates of the speculum mirror began to feel the challenge of the refractor, Dr. Nevil Maskelyne, English Astronomer Royal, ventured the opinion "that the aperture of a common reflecting telescope, in order to show objects as bright as the achromat, must be to that of an achromatic telescope as 8 to 5."
The relative inefficiency of the reflector of that day was due to the fact that, even under most favorable circumstances, barely 40 per cent of the original light escaped absorption by the metal mirrors, the greatest losses occurring in the short and medium wave lengths. Even silver-on-glass mirrors are subject to considerable deterioration, especially under certain conditions of the atmosphere.
Coming down to figures - due to reflection there occurs in an untreated lens a light loss of slightly more than four per cent at each of its surfaces.
With reflection losses to be accounted for, plus an absorption loss in the substance of the glass (amounting to about two per cent for lenses of moderate size), it is evident that about 82 per cent of the original light is transmitted. In the reflector, after first deducting that area of the mirror's surface obscured by the diagonal, an equal percentage of the original light is found to be transmitted.
Of course, this transmitted light is subject to another reflection by the diagonal, but the refractor will probably employ a star diagonal, the function of which is similar to that of the diagonal or prism of the Newtonian, so an equivalent loss may occur there. Therefore, for those engaged in amateur telescope making, with either instrument, the same amount of light reaches the eyepiece.
It was discovered, however, in the latter part of the last century by those involved in who make telescopes that some lenses which had been tarnished by the elements transmitted more light than ones that were newly polished; it was found that this resulted from lessened reflections at the tarnished surfaces. Various processes of producing an artificial tarnish were attempted. At present, in the most satisfactory method, metallic salts (such as magnesium fluoride) are evaporated in a high vacuum onto the glass. Ideally, the refractive index of an anti-reflection fluoride coating should vary from that of glass at the glass-fluoride surface to that of air at the fluoride-air surface, in which case no reflection would occur.
Practically, the index of the coating should be equal to the square root of the index of the glass, and its thickness equal to a quarter of a wave length of yellow-green light. Then, if a refractor is contemplated, additional experience can be gained by making the optical flat that is so essential in the testing and figuring of the objective lens.
If you decide to begin to make a telescope, the experience of thousands of amateurs has shown that one's teeth should first be cut on at least one good mirror. Then, if a refractor is contemplated, additional experience can be gained by making the optical flat that is so essential in the testing and figuring of the objective lens.
BESTSELLING Research Scope Binocular Achromatic Objectives
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