Astromania 50mm Compact Deluxe Finder & Guidescope Kit with 1.25" Double Helical Focuser - Guiding with the Mini-Guide Scope: So astrophotography is easier and less equipment Mini-guide tube to quickly find objects and guiding stars, designed both for visual, as well as for photographic use.Take any 1.25 inch eyepieces in your collection, worm-focuser: fast focusing. Prevents rotation of the camera and eyepiece. Or use it as a comfortable, large viewfinder to waste less time finding objects in visual observation. 190mm focal length. Compact mini guide scope designed for use with astrophotography telescopes up to 1500mm focal length with bright, wide-field optics puts numerous potential guide stars in view so you'll never have to search for one! Adjustable-aim dovany weight to an astrophotography setup and can conveniently be stashed in an accessory case between uses. "Dovetail guide scope bracket installs on virtually any astrophotography telescope quickly and easily. The sturdy metal housing made of black anodized aluminum. Looking out not only solid, but is also very robust. A milled and knurled ring allows easy and precise fine focus adjustments. It comes with matching pipe clamps and a Synta-style mounting plate to make assembly and installation as easy as possible. Have a built-in worm-focuser with Brass Compression Ring and 2 thumbscrews,40mm focusing range (10mm focusing range with micro-focusing Helical focuser, the rest is by a fixable, scaled drawtube) is made possible by an extremely precise focus adjustment. The mechanism has a determined orientation: This is mounted cameras or eyepieces - and thus also the area with your guide stars - not rotate during focusing. The 50mm Multi-Use Guide Scope features a precision helical focuser that makes it easy to focus your guide stars quickly and precisely. The focuser, made of machined, anodized aluminum, is the non-rotating variety, meaning the guide camera does not rotate when focus is adjusted, but rather moves in or out in fixed orientation, which is important for hassle-free focusing. You dont want stars rotating in the field of view when youre trying to focus! Drawtube travel of the helical focusing mechanism is 10mm and the motion is extremely smooth and fine. The built-in extension tube can add up to 30mm of additional length, to allow focus to be achieved with most autoguiders available on the market as well as 1.25&#034; eyepieces for use of the 50mm Multi-Use Guide Scope as a visual finder scope. Just loosen the extension tube locking thumbscrew, slide the extension tube out to the desired length, then re-tighten the thumbscrew. When tightened down, you should not notice any flexure in the extension tube; it is remarkably rigid. The top of the extension tube features an engraved millimeter scale to aid in returning to the exact extension tube length needed for critical focus, should you need to switch between eyepieces and autoguider. Make sure your autoguider is powered on and connected to your laptop computer, and that the software you will use for autoguiding is up and running. Also, make sure the focus lock thumbscrew is not tightened down. With the imaging software set to take continuous exposures, rotate the knurled helical focus ring clockwise or counterclockwise while you watch the star images themselves or the reference numbers from your software on your laptop screen. If you cant see any stars, you likely need to move the extension tube in or out slowly until you see some, then continue with the fine focusing using the helical focuser. When the stars become reasonably sharp, or youve reached the lowest FWHM, youre done! Once focus is achieved, the focus lock thumbscrew can be lightly tightened to ensure the drawtube remains set at that position,although this may not even be necessary.Theres little need to tighten this thumbscrew firmly since most guide cameras are relatively lightweight, and doing so could put sideways pressure on the drawtube that might knock your carefully set focus off a bit. For best results we recommend focusing the guide camera 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. The 50mm Multi-Use Guide Scopes mounting bracket has a Vixenstyle dovetail bar that can be mounted to your telescope in different ways. First, it fits the standard dovetail finder scope base included on many telescopes. Simply slide it into the dovetail base, then tighten the thumbscrew on the base to secure the guide scope in place. The brackets dovetail bar has one &#034;-20 (center) and two M8x1.25 threaded holes for attachment to an optional universal dovetail plate. In the guidescope is mounted on a telescope. To keep dust from getting inside the guide scope and from accumulating on the objective lens, keep the front and rear caps installed when the guide scope is not in use. We recommend storing the guide scope in a padded accessory case. Cleaning the Lens: Although it shouldnt need cleaning very often, you can clean the front lens of theguide scope with any quality optical lens cleaning tissue and optical lens cleaning fluid designed for multi-coated optics. Never use regular glass cleaner or cleaning fluid designed for eyeglasses. Before cleaning with fluid and tissue, eject any loose particles from the lens with a blower bulb, compressed air, or a soft brush such as a LensPen. Then apply some cleaning fluid to a lens tissue, never directly on the optics. Wipe the lens gently in a circular motion, then remove any excess fluid with a fresh lens tissue. Oily fingerprints and smudges can be removed using this method. Use caution, as rubbing too hard may scratch the lens. Never re-use the same tissue.