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Index.F.Qxp 2/8/07 4:15 PM Page 411 14389_Harrington_4p_bindex.f.qxp 2/8/07 4:15 PM Page 411 Index Abbé, Ernst, 15, 25 aperture, 2–3 aberrations Apogee Instruments, binoculars, astigmatism, 20, 34–35, 322, 324 59–61 chromatic, 12, 28, 31, 180 apparent field of view, coma, 16–17, 20, 35 177–178 pinched optics, 322, 324 astigmatism. See aberrations, rough optical surface, 323, 324 astigmatism spherical, 12, 13, 34, 90, 180, Astromeccanica, binoculars, 61 322–323, 324 astronomical resources, accessories, must-have, 277 401–403 accessory tray, homemade, Astronz, Newtonian reflectors. 292–293 See Guan Sheng Optical, achromatic lens, 13 Newtonian reflectors adapters, camera-to-telescope, Astro-Physics, apochromatic 260 refractors, 96 Airy disk, 6–7 AstroSystems, Newtonian reflectors, Airy, George, 6 111–112 altitude-azimuthCOPYRIGHTED mounts. See autocollimator, MATERIAL 227, 228 mountings, telescope averted vision, 345 angle of incidence, 57 Antares, Newtonian reflectors. See Guan Sheng Optical, Barlow lens, 182, 196–198, Newtonian reflectors 199–200 Anttler Optics, Newtonian Barska, binoculars, 61–62 reflectors. See Guan Sheng batteries, 84 Optical, Newtonian binocular mounts. See mountings, reflectors binocular 411 14389_Harrington_4p_bindex.f.qxp 2/8/07 4:15 PM Page 412 412 INDEX binoculars. See also brand names, Schmidt-Cassegrain telescopes, 39, 25–27, 53–79 139–145 aperture, 54 chairs, observing. See observing coatings, 57–58 chairs diopter adjustment, 58 chart table, homemade, 278–281 exit pupil, 54 Cheshire eyepiece, 227–228 focusing, 58 Chrétien, Henri, 20 giant, 58 Christmas Trash Telescopes, 80 interpupillary distance, 59 chromatic aberration. See magnification, 54 aberrations, chromatic Porro prism, 26, 55, 56 Clark, Alvan, 15 prisms, 56–57 cloaking device, light-pollution, recommendations, 78 346 roof prism, 26, 55–56 clothing, cold weather, 261–262 specifications, 351–356 coatings, optical, 31, 57–58, 139–140, twilight factor, 54 145 zoom, 54 collimation, 35, 315–321 binocular viewers, 198, 200–203 Newtonian reflector, 316–319 books and publications, Schmidt-Cassegrain, 319–321 recommended, 232–238 collimation tools, 227–230 Bouwers, A., 21 color filters. See filters, lunar and Bushnell, binoculars, 62 planetary coma. See aberrations, coma coma correctors, 205–206 cameras, 242–258 computer software, recommended, CCD, 248–257 238–240 consumer digital, 244–246 contrast, image, 31–32, 40 film, 242–244 conventions, astronomical, 334–335 lenses, 258–259 Coronado solar refractors, 107–109 video, 257–258 corrector plate, 1 webcams, 246–248 Criterion Manufacturing Company, Canon, binoculars, 62–63 23 Carton Optical, binoculars, 63 crown glass, 13 Cassegrain reflector. See telescope, curvature of field, 180 reflector, Cassegrain Cassegrain, Sieur, 17 catadioptric telescopes. See Dall, Horace, 20 telescope, catadioptric Dall-Kirkham telescopes. See celestial coordinates, 336–336 telescope, reflector, Celestron International Cassegrain achromatic refractors, 82–86 Dawes’ Limit, 6–9 apochromatic refractors, dew-prevention systems, 264–267 96–97 homemade, 289–290 binoculars, 64–65 DGM Optics, reflectors, 138–139 eyepieces, 187 diffraction limited, 24 Maksutov telescopes, 149 digital setting circles, 240–242, Newtonian reflectors, 112–113 339–340 14389_Harrington_4p_bindex.f.qxp 2/8/07 4:15 PM Page 413 INDEX 413 Discovery Telescopes, Newtonian Plössl, 182, 183–184 reflectors, 114–115 Ramsden, 181, 182 Dobson, John, 45 real field of view, 179 Dobsonian mounts. See mountings, reticle, 206–207 telescope RKE, 182–183 Dollond, John, 13 Sky Instruments Antares W70, 191–192 Speers-Waler, 191 Edmund Scientific, reflectors, 115 specifications, 371–379 English/metric conversion, 405 Takahashi LE, 192 equatorial mounts. See mountings, Tele Vue telescope Nagler, 192–193 exit pupil, 54, 175–177 Panoptic, 193 eye, human, 344–346 Radian, 193–194 eyecups, 231 VERNONscope Brandon,194 eyepiece cases, 232 Vixen eyepieces, 173–209 Lanthanum LV, 194 Abbé. See eyepieces, orthoscopic Lanthanum Superwide, 194 aberrations, 180 William Optics apparent field of view, 177–178 SWAN, 194–195 Celestron International UWAN, 194–195 Axiom, 187 zoom, 195–196 X-Cel, 187 eye relief, 58, 179 coatings, 180 components, 173–175 Erfle, 186 filters, 83, 217–227 Guan Sheng Optical, Superview, hydrogen-alpha. See also Coronado 188 solar refractors, 226, Huygens, 181, 182 228–229 Kellner, 181–182 light-pollution reduction, Kokusai Kohki, Wide Scan Type 217–220 III, 188 lunar and planetary, 220–224 magnification, 175, 176 minus violet, 83 Meade Instruments solar, 224–227 QX, 188 finders, 211–217 Super Wide Angle, 188 aligning, 308–309 Ultra Wide Angle, 188–189 finderscopes, 211–212, 213–214, monocentric, 182, 185–186 215 Orion Telescopes mounts, 216–217 DeepView, 189 unity finders, 212, 215–216 Epic ED-2, 190 dew heater, homemade, Expanse, 190 289–290 Optiluxe, 189–190 finding sky objects, 335, Stratus, 190 337–340 Ultrascopic, 189 flashlights, 263–264 orthoscopic, 182, 184–185 flint glass, 13 Pentax XW, 190–191 flip mirrors, 260–261 14389_Harrington_4p_bindex.f.qxp 2/8/07 4:15 PM Page 414 414 INDEX focal length, 3 Jim’s Mobile focal ratio, 3 binoculars, 67 focal reducers, 203–204 Newtonian reflectors, 116–117 focuser handle, homemade, 287–289 JMI. See Jim’s Mobile fork equatorial mounts. See mountings, telescope, equatorial Kepler, Johannes, 11–12 Foucault, Jean, 19 Kirkham, Allan, 20 Fraunhofer, Joseph von, 14 Kowa binoculars, 68 Fujinon binoculars, 65–67 laser collimators, 228, 229–230 Galileo, 3, 10 collimator, homemade, 281–282 German equatorial mounts. See lens mountings, telescope, cameras, 258–259 equatorial extra-low-dispersion glass, 30 giant binoculars. See binoculars, fluorite glass, 30 giant special-dispersion glass, 30 goggles, light-pollution, 346 light loss, 20 GoTo mounts. See mountings, light-gathering ability, 4–5 telescope, GoTo light pollution, 35, 330 Gregory, James, 15 cloaking device, 346 Gregory, John, 21–22 goggles, 346 Gregory-Maksutov. See telescope, light-pollution reduction filters. See catadioptric, Maksutov filters, light-pollution Guan Sheng Optical reduction eyepieces, 188 Lippershey, Jan, 10 Newtonian reflectors, 116 locating sky objects, 335, 337–340 Guinard, Pierre Louis, 13–14 LPR filters. See filters, light-pollution reduction Hadley, John, 18 Hall, Chester, 13 Mag One Instruments, reflectors, Hensoldt, Moritz Carl, 26 118 Herschel, William, 18 magnification, 4 Hevelius, Johannes, 12 versus aperture (table), 176 hydrogen-alpha filters. See filters, eyepieces, 175, 176 hydrogen-alpha magnitude, limiting, 5 mail-order problems, 171 Maksutov, Dimitrii, 21 index of refraction, 57 Maksutov telescope. See telescope, insect repellent, 263 catadioptric, Maksutov International Dark-Sky Association, MC Telescopes, Newtonian 330 reflectors, 118–119 Internet resources, 401–403 Meade Instruments Intes Micro, Maksutov telescopes, achromatic refractors, 86–87 149–150 binoculars, 68 14389_Harrington_4p_bindex.f.qxp 2/8/07 4:15 PM Page 415 INDEX 415 exotic catadioptric telescopes, 146, observing chairs 152–156 commercial, 267–269 eyepieces, 188–189 homemade, 282–287 Maksutov telescopes, observing site selection, 333–334 150–152 Obsession Telescopes, Newtonian Newtonian reflectors, reflectors, 121–123 119–120 obstruction, central, 31–32 Schmidt-Cassegrain telescopes, Optical Guidance Systems, 145–146 Cassegrain reflectors, minus violet filters. See filters, minus 136–137 violet optical quality, 24–25. See also star test mirror flotation system, 33 Orion Telescopes Miyauchi, binoculars, 68–69 achromatic refractors, 27, 87–90 Moon filters. See filters, lunar and apochromatic refractors, 97–98 planetary binoculars, 73–75 mountings eyepieces, 189–190 binocular, 269–273 Maksutov telescopes, 152 telescope, 44–49, 157–169 Newtonian reflectors, 123–127 altitude-azimuth, 44–45 Schmidt-Cassegrain telescopes, comparison table, 158–164 147–149 Dobsonian, 44, 45 equatorial, 44, 46–48 equatorial table, 165–168 parfocal, 179 homemade, 294–298 Pentax GoTo, 44, 48–49 binoculars, 75 maintenance, 314 eyepieces, 190–191 rap test, 46 phase coating, 56 setting up, 303–309 polar alignment, 340–343 using, 343–344 Poncet mount. See mountings, telescope, equatorial table Porro prism binoculars. See nebula filters. See filters, light- binoculars, Porro prism pollution reduction Porter, Russell, 16 Newton, Isaac, 3, 16 power. See magnification Newtonian reflector. See telescope, primary mirror, 1 reflector, Newtonian prime optic, 1 NightSky Scopes, Newtonian projects, homemade, 278–302 reflectors, 120–121 accessory tray, 292–293 night vision, 344–345 chart table, 278–281 Nikon, binoculars, 70–71 dew heater for unity finder, 289–290 equatorial table, 294–298 Oberwerk, binoculars, 71–73 focuser handle, 287–289 objective lens, 1 laser collimator , 281–282 observatories observatory, 299–302 commercial, 273–276 observing chair, 282–287 homemade, 299–302 vibration damper, 290–292 14389_Harrington_4p_bindex.f.qxp 2/8/07 4:15 PM Page 416 416 INDEX rap test, 46 apochromatic refractors, 99 Rayleigh’s Criterion, 24, 34 Newtonian reflectors, 127–129 RC Optical Systems, Cassegrain societies, astronomical, 401 reflectors, 137 solar filters. See filters, solar real field of view, 179 spherical aberration. See aberrations, record keeping, 346–348 spherical reflecting telescopes. See telescope, star diagonals, 29, 230–231 reflector Stargazer Steve, Newtonian refracting telescopes. See telescope, reflectors, 129–131 refractor star-hopping, 337–339 resolving power, 6–7 Starmaster telescopes, Newtonian Ritchey, George, 20 reflectors,
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