How to Collimate a Telescope - Orion Telescopes and Binoculars

hello i'm brian with the ryan telescopes and binoculars and i'm going to demonstrate how to collimate the sky quest xt8 Dobsonian reflector the steps I'm going to show you also apply to all other Orion tops onions as well as Orion's Newtonian optical tube assemblies collimation is the alignment of your telescopes optics that enable the best focused possible you can think of collimating your telescope a lot like tuning a musical instrument it's something you periodically have to check for and occasionally make adjustments once you get the hang of collimation it's really a rather quick and simple process which only takes a few minutes to complete one of the most simple and effective ways to collimate your telescope is to do so visually with the assistance of a tool the xt8 includes a collimation cap which is basically simple cap with the hole punch down the center and reflective surface in the back this is used to help you Center your eye over the focuser while you perform the collimation that I will show you in just a moment the only other required tools are a Phillips head screwdriver which is also included with the XT eight and you will have to supply your own two millimeter allen wrench or hex key start by removing the dust caps from your telescope from the objective and the focuser and position your telescope so that it's pointed horizontally this is a good safety precaution because while you're working on the telescope you don't want to chance dropping anything into the optical tube and onto your primary mirror now the order in combination remember this order you always want to adjust your secondary mirror towards the top of the telescope first then proceed to adjust the primary here here's a recommended tip to help you start aligning your secondary mirror take an ordinary white sheet of paper and place it inside of the telescope directly opposite the focuser and while doing so be careful not to touch the reflective surface of the secondary mirror this is going to help you align your secondary mirror because it's going to provide a brighter background to help make the secondary standout while you're looking through the focuser and performing the collimation start by inserting the collimation cap into the focuser and look through the collimation cap you will see a series of reflections they may not at all be centered but that's okay right now we're not concerned with the reflections for the time being we just want to look at the secondary mirror and where it is located in relation to the focuser you keep in mind that the Orion telescopes are factory lined you shouldn't ordinarily have to make very large adjustments but it's still something you want to check and make sure that everything is aligned correctly look into the combination cap and see where the secondary mirror is located in relation to the focuser if it's too close to the front of the telescope front opening or if it's too close to the back of the telescope or the primary mirrors you'll need to make an adjustment starting with a two millimeter allen wrench loosen the three socket head screws in front of the secondary mirror you only need to make about one turn maybe two turns of adjustment just by loosening the three socket head screws and remember not to do this with a telescope pointing vertically otherwise you chance dropping the tool onto your primary mirror and that mistake can very easily happen now take your Phillips head screwdriver position it over the center screw above the secondary mirror and secure the stock in front of the secondary mirror with your hand while making the adjustments to the screw turning this screw counterclockwise is going to push the secondary mirror towards the primary turning a clockwise is going to pull it forward towards the front opening of the telescope now look through the collimation cap while you make this adjustment until the secondary mirror appears to be centered in front of the focuser one more important tip is to make sure that the secondary mirror doesn't rotate out of position while you make this adjustment and that can very easily happen so just look through the combination cap while you make this adjustment and make sure that the secondary mirror is in fact facing the focuser the last remaining step to complete collimating the secondary mirror of your telescope is to adjust the tilt of the secondary mirror look through the collimation eyepiece you're still going to see a series of reflections which may not be centered right now concentrate on looking at the reflection of the primary mirror in the secondary mirror reflection will be an image of the primary mirror in the secondary you want that to be centered and to do so you will take your 2 millimeter allen wrench and adjustments to the three socket head screws you no longer need to make any adjustments to the center screw only the three socket head screws and you want to make sure you have tension on all three screws because if you don't the mirror can very easily move out of place later now the good news is you don't actually have to make these adjustments to your secondary mirror very often because it doesn't weigh very much and it is secured in place very well once you have the three screws tighten down when you're completed you should be able to look through the combination eyepiece and see the primary mirror centered in the secondary mirror but you're still going to notice that something is out of collimation and that's your primary mirror and that's what we're going to do next now that you've completed aligning your secondary mirror you can go ahead and remove the white sheet of paper if you place one inside don't forget about this because this sheet of paper can also slide down onto your primer here and now it's time to align the primary mirror of your telescope all orion reflectors including orion Dobsonian x' feature a very useful reference point which is the center mark on the primary mirror looks like a little circle now this center mark is going to be used to reference the center of your collimation cap the goal is to get the center mark on your collimation cap aligned with the center mark on the primary mirror collimation cap looks like a dot the mark on the primary mirror looks like a little circle simply get the circle to align with the dot so that makes a bull's-eye and to do so we're going to access the primary mirror cell of the Xth you're going to notice set of six screws there are three taller collimation locking screws and three shorter collimation adjustment screws start by loosening the three collimation locking screws give it about one to two turns to loosen it this actually won't affect the alignment to actually adjust the tilt you're going to turn the three collimation adjustment screws check your progress by looking through the collimation cap now due to the length of the xt8 and many Dobsonian x' and other reflectors you can't reasonably make this adjustment while looking through the collimation cap at the same time so it's a good idea just to make small adjustments than to check your progress by looking back into the collimation cap you can also have a buddy help you have them look through the eyepiece while you make the adjustments make the adjustments as necessary until the center mark on the primary mirror is aligned with the opening on the collimation cap again it should make a bull's-eye once you've completed this adjustment you're collimated and just make sure that you tighten down the three collimation locking screws again what I like to do is also double check that while you tighten this down you don't actually make it so tight that it moves out of place again so I make one last reality check into the collimation eyepiece just to make sure that everything is still aligned and you're done and now you're still yours telescope should say fairly well aligned you at this point you only need to make small adjustments from here on unless it gets handled very roughly another very easy and popular way to collimate your reflector telescope is to use an optional laser collimator such as the orion laser mate deluxe it's very easy to use and what's more is you can actually use this at night once you get the hang of it because all you're doing is aligning the dots in the telescope where you see the laser being hit the mirrors when collimating your reflector with the laser in a collimator there are two key adjustments to make align the secondary mirror towards the front of the telescope you want to line the tilt of the secondary and you also want to align the tilt of the primary towards the back remember this order always aligned the tilt of the secondary mirror first then proceed to align the primary mirror start by removing the dust cap sorry optical two and when you make your adjustments keep your telescope pointing horizontally don't point it vertical because you can chance dropping something down into the telescope onto your primary mirror which you don't want so keep it or azan ttle now install the laser mate deluxe Calma later with the target viewer facing towards the back of the telescope or towards the primary so go ahead and insert laser collimator now as with any laser product use caution and don't point it at anyone start before you actually turn the laser collimator on point your telescope at a white wall then turn on the laser collimator and just check to see that you don't have a red dot pointing at the wall so right now a red dot is not pointing at the wall so I know that my collimation isn't so far off that the beam is actually exiting the telescope that means it's safe for me to actually look into the optical tube to start the collimation process now if it turns out the beam is hitting the wall that's okay just use caution before putting your eyes in front of the optical path of the telescope we start by aligning the secondary mirror the only tool necessary for this is a two millimeter allen wrench or hex key look into the optical tube with the laser on you'll see the dot where the laser strikes the mirror you will also see the center mark of the primary mirror all Orion reflectors feature the center mark which is a very useful reference to show you exactly where the center of the primary mirror is the goal is to make the adjustment to the three socket head screws with your two millimeter allen wrench until the dot on the primary mirror aligns with the center mark and that's all you need to do it's actually very easy with the laser make sure that attention is applied to all three socket head screws when you're completed with the secondary alignment just to make sure that the mirror does not move at a place later the mirror is very light and there isn't much adjustment needed after you initially get your secondary aligned now that we've aligned the secondary mirror it's time to align the primary mirror and this is where a very convenient to have the laser meet the lux collimator because we have the target viewer which allows us to view the alignment of the primary while accessing the cell the back of the telescope you don't have to walk back and forth from the primary mirror cell to the focuser so it's a great added convenience so to make the adjustment we need to access the primary mirror so you'll see that there is a series of six screws there are three collimation locking screws and three collimation adjustment screws start by loosening the three combination locking screws about a turn or so just to give us enough room to make the adjustment then while looking at the target viewer of the laser Vein deluxe collimator make slight adjustments to the three collimation adjustment screws and you want to walk the beam into the center the dot into the center mark what will happen when you get it aligned it will appear to be like somewhat of an eclipse like seen here alaska it'll actually mask itself in that center opening once you've done that your primary mirror is actually like now just lock the three combination cocking screws again and make sure while doing so that you don't knock it out of alignment you shouldn't have to tighten it down very much and you're set and it's very simple and very quick to do with the laser collimator

Channel: Orion Telescopes & Binoculars

Views: 397,556

Rating: 4.8648648 out of 5

Keywords: collimation, collimate, telescope, telescopes, orion, space, astronomy, reflector, dobsonian, laser, alignment, mirror, stars

Id: YAVGcGEBmCE

Length: 12min 46sec (766 seconds)

Published: Wed Jan 05 2011