Évaluations - 3, GPA: 5
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Photos et spécifications Celestron C9.25-S |
Facilité d'utilisation
If you find that the ring pattern is skewed in a different direction, than simply repeat steps 2 through 6 as described above for the new direction. Perfect collimation will yield a star image very symmetrical just inside and outside of focus. In addition, perfect collimation delivers the optimal optical performance specifications that your telescope is built to achieve. Figure 8-3 A collimated telescope should appear symmetrical with the central obstruction centered in the star's diffraction pattern. If seeing (i.e., air steadiness) is turbulent, collimation is difficult to judge. Wait until a better night if it is turbulent or aim to a steadier part of the sky. A steadier part of the sky is judged by steady versus twinkling stars. 45 You will find that additional accessories enhance your viewing pleasure and expand the usefulness of your telescope. For ease of reference, all the accessories are listed in alphabetical order. Adapter AC (#18773) -Allow DC (battery powered) telescopes to be converted for use with 120 volt AC power. Auxiliary Port Accessory (#93965) – This accessory plugs into the auxiliary port of the telescopes control panel to provide additional ports for accessories like the CN-16 GPS as well as a PC programming port. Barlow Lens -A Barlow lens is a negative lens that increases the focal length of a telescope. Used with any eyepiece, it doubles the magnification of that eyepiece. Celestron offers two Barlow lens in the 1-1/4" size. The 2x Ultima Barlow (#93506) is a compact triplet design that is fully multicoated for maximum light transmission and parfocal when used with the Ultima eyepieces. Model #93326 is a compact achromatic Barlow lens that is under three inches long and weighs only 4 oz. It works very well with all Celestron eyepieces. Erect Image Diagonal (#94112-A) -This accessory is an Amici prism arrangement that allows you to look into the telescope at a 45° angle with images that are oriented properly (upright and correct from left-to-right). It is useful for daytime, terrestrial viewing. Eyepieces -Like telescopes, eyepieces come in a variety of designs. Each design has its own advantages and disadvantages. For the 1-1/4" barrel diameter there are four different eyepiece designs available. • OMNI Plossl -Plossl eyepieces have a 4-element lens designed for low-to-high power observing. The Plossls offer razor sharp views across the entire field, even at the edges! In the 1-1/4" barrel diameter, they are available in the following focal lengths: 4mm, 6mm, 9mm, 12.5mm, 15mm, 20mm, 25mm, 32mm and 40mm. • X-Cel -This 6 element design allows each X-Cel Eyepiece to have 20mm of eye relief, 55° field of view and more than 25mm of lens aperture (even with the 2.3mm). In order to maintain razor sharp, color corrected images across its 55° field of view, extra-low dispersion glass is used for the most highly curved optical elements. The excellent refractive properties of these high grade optical elements, make the X-Cel line especially well suited for high magnification planetary viewing where sharp, color-free views are most appreciated. X-Cel eyepiece come in the following focal lengths: 2.3mm, 5mm, 8mm, 10mm, 12.5mm, 18mm, 21mm, 25mm. • Ultima -Ultima is our 5-element, wide field eyepiece design. In the 1-1/4" barrel diameter, they are available in the following focal lengths: 5mm, 7.5mm, 10mm, 12.5mm, 18mm, 30mm, 35mm, and 42mm. These eyepieces are all parfocal. The 35mm Ultima gives the widest possible field of view with a 1-1/4" diagonal. • Axiom – As an extension of the Ultima line, a new wide angle series is offered – called the Axiom series. All units are seven element designs and feature a 70. extra wide field of view (except the 50mm). All are fully multicoated and contain all the features of the Ultimas. Filters Sets, Eyepiece -Celestron offers four convenient filter sets, which contain four different filters per set. Not only are these highly useful filter combinations, but they also offer an economical way to add versatility to your filter collection. Series 1 – #94119-10 Orange, Light Blue, ND13%T, Polarizing (#s 21, 80A, 96ND-13, Polarizing) 46 Series 2 – #94119-20 Deep Yellow, Red, Light Green, ND25% T (#s 12, 25, 56, 96ND-25) Series 3 – #94119-30 Light Red, Blue, Green, ND50% T (#s 23A, 38A, 58, 96ND-50) Series 4 – #94119-40 Yellow, Deep Yellow, Violet, Pale Blue (#s 8, 15, 47, 82A) Flashlight, Night Vision - (#93588) -Celestron’s premium model for astronomy, using two red LED's to preserve night vision better than red filters or other devices. Brightness is adjustable. Operates on a single 9 volt battery (included). CN16 GPS Accessory (#93963) - Plug in this 16-channel GPS module into your telescopes drive base port to link up and automatically download information from one of many global positioning satellites. Controlled with the computerized hand control, the CN-16 will greatly improve the accuracy of your star alignments. CN16 GPS Bracket (#93964) – Support your C...
Ce manuel est également adapté pour les modèles :Instruments d'optique - C5-S (4.03 mb)
Instruments d'optique - C8-S (4.03 mb)