============================================================================= | |Numerical | Micrometer | Price No. of Objective|Focal length |Aperture | Values | $ | |(num. aper.)| | ————————————————+——————————————+————————————+————————————————+——————————————— Low power { 1*|44 mm (1-3/4")| 0,09 | 0,054 mm = 54µ | =3.25=[1] Dry { 1 |44 mm (1-3/4")| 0,09 | 0,054 mm = 54µ | =6= Series { 1a| 39-27 mm | 0,06--0,10 | 50--26µ | =10= (adjustable | | | | mounting) { 2 |30 mm (1-1/4")| 0,14 | 0,028 mm = 28µ | =6= { 3 |18 mm (3/4) | 0,28 | 0,015 mm = 16µ | =6= { 4 | 8 mm (1/3) | 0,55 | 0,009 mm = 9µ | =10= ————————+——————————————+————————————+————————————————+——————————————— High power { 5 |5,8 mm (1/4") | 0,77 |0,0045 mm = 4,5µ| =10= { 6 |4,4 mm (1/6") | 0,82 |0,0034 mm = 3,5µ| =12= (Fluorite) { 6a|4,4 mm (1/6") | 0,82 |0,0034 mm = 3,5µ| =16=[2] { 7 |3,2 mm (1/8") | 0,85 |0,0026 mm = 2,6µ| =12= (Fluorite) { 7a|3,2 mm (1/8") | 0,85 |0,0026 mm = 2,6µ| =16=[2] " { 8 |2,5 mm (1/10")| 0,87 |0,0020 mm = 2,0µ| =16= " { 9 |2,2 mm (1/12")| 0,87 |0,0017 mm = 1,7µ| =24= ————————+——————————————+————————————+————————————————+——————————————— Water- | | | | Immersion 10|2,2 mm (1/12")| 1,10 |0,0017 mm = 1,7µ| =26= ————————+——————————————+————————————+————————————————+——————————————— Homogeneous{1/10|2,5 mm (1/10")| 1,30 |0,0022 mm = 2,2µ| =30= Oil- {1/12|2,1 mm (1/12")| 1,30 |0,0017 mm = 1,7µ| =40= Immersion {1/16|1,7 mm (1/16")| 1,30 |0,0014 mm = 1,4µ| =60= ============================================================================= [Footnote 1: Objective 1* consists of only one doublet, carefully corrected. It is sufficient for many purposes, though it does not possess the same brilliancy of field as the No. 1 objective.] [Footnote 2: The objectives 6a. and 7a. are better corrected in achromatism than the regular No. 6 and 7.] =Magnification= of the Achromatic and Apochromatic Objectives in combination with the Huyghenian Eye-pieces. Tube-length 170 mm. Distance of image 250 mm.