Assessments - 3, GPA: 3.7
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Facilidade de uso
It’s ideal for guiding long-exposure astrophotographs with short to medium focal length telescopes up to 1500mm focal length. Its bright, wide-field optics serve up lots of potential guide stars on your autoguider’s CCD sensor, and it’s small enough to stash in an accessory case! Adjustment thumbscrews (x3) Lock ring Thumbscrews, camera attachment Objective lens cell O-ring (not visible) Bracket Adapter plate 1.25" Holder Dovetail foot Socket head screws (x2) #8-32 Screws 1.5mm Allen Hex nuts wrench Dovetail base 1.25" Parfocal ring Figure 1. The Mini 50mm Guide Scope and included components Parts list 1 Guide scope optical tube assembly 1 Dovetail bracket 1 Dovetail base 2 #8-32 x 3/8" flat (countersunk) Phillips head screws, and 2 hex nuts 2 #8-32 x ." length flat (countersunk) Phillips head screws 1 Adapter plate 1 Socket head screw, ."-20 x 1" 1 Socket head screw, ."-20 x 1/2" 1 Parfocal ring, 1.25" 1 Allen wrench, 1.5mm assembly The Mini Guide Scope comes fully assembled and mounted in the dovetail bracket. Refer to Figure 1 to familiarize yourself with the features and parts of the guide scope. Mounting the Mini Guide Scope The Mini 50mm Guide Scope’s mounting bracket has a dovetail foot that fits the Orion dovetail finder scope base included on many Orion telescopes. The guide scope also comes with a separate dovetail base (Orion part #7214), with two #8-32 x 3/8" flat Phillips-head screws and two hex nuts, for custom installations. To mount the Mini 50mm Guide Scope on a dovetail plate such as Orion’s Wide or Narrow Universal mounting plates, or similar plates produced under other brands, we’ve included an adapter plate that makes it easy. The Mini Guide Scope can then be piggybacked on top of your main instrument’s tube rings, or on a side-byside saddle plate, for autoguiding. On the adapter plate there are three threaded holes. The two outer ones are for attaching the dovetail base to the adapter plate, using the two included #8-32 x ." length flat (countersunk) Phillips head screws. (These are the longer of the four #8-32 screws.) Once the dovetail base is securely attached, you can mount the adapter plate onto a dovetail mounting bar or plate by inserting one of the supplied 1/4"-20 socket head screws up through an unthreaded hole or slot in the dovetail plate and into the ."-20 hole in the center of the adapter plate. Tighten with a 3/16" Allen wrench (user supplied). We have provided two different socket head screws for your convenience, one is ." long, the other 1" long. Choose the one that best fits your mounting bar or plate. 4 5 Once you’ve achieved the best focus you can get, lightly re-tighten the lock ring by turning it clockwise while holding the objective lens cell steady. You’re done! Of course, if you turn the objective lens cell until it can rotate inward no further, or you rotate it outward so far that it unthreads completely and comes off, you should reset it to about the midpoint of its thread travel and re-adjust the coarse focus, i.e., the position of the autoguider nosepiece in the 1.25" holder. Then, you can attempt to fine- focus again using the objective lens cell. Setting the Parfocal ring Once the guiding camera’s nosepiece has been set at the optimal focus position following the above procedure, you can lock the parfocal ring on the camera’s nosepiece. This will enable you to return the camera to the same position in the guide scope’s holder on subsequent imaging sessions (assuming you remove the camera from the guide scope after each session), obviating the need to go through the coarse focusing procedure (steps 2 and 3 above) again. You should still, of course check the guide scope’s focus at each imaging session. But if any adjustment is needed, it will probably be minor and can be done using the fine focus of the objective lens cell (step 4 above). To set the parfocal ring, which you inserted on the guide camera’s nosepiece in step 1 above, simply slide it forward until it lies flush against the guide scope’s 1.25" holder (Figure 5). Then carefully tighten each of the three setscrews in the ring. Focusing Focusing can be done in daylight on a distant object, or at night under the stars. For best results we recommend doing final, fine focusing at night at the beginning of your imaging session, following the focusing procedures in the imaging software you use for astrophotography, such as MaxIm DL, PHD Guiding, or Images Plus. 1. Slide the 1.25" parfocal ring onto the nosepiece of your autoguiding camera (Figure 2). If it doesn’t slip on easily, make sure the three setscrews in the ring are backed off enough to provide clearance for the nosepiece. A 1.5mm Allen wrench is provided for adjusting the setscrews. Leave the ring loose on the nosepiece; do not tighten the setscrews yet. 2. Next, insert the nosepiece of your guide camera about halfway into the 1.25" holder of the guide scope, then lightly tighten the three thumbscrews on the holder to temporarily secure the a...