SVBONY Red Laser Collimator for Newtonian Marca Telescope Alignment 1.25 inches 7 Bright Levels Triple Cemented Lens with 2 inches Adapter

Good range of brightness levels. Came reasonably collimated (adjustable). Works great with the Barlowed laser technique. Really easy and effective! Brightness: quite dim on the lowest setting to quite bright by the 4th or 5th. Collimation/alignment of the laser itself. I setup a fixture using Legos (great suggestion I read online), placed it on a granite countertop (tape the fixture to the countertop so it won’t move), and targeted the wall 6 meters away. The diameter of the circle traced on the wall as I rotated the laser on the fixture was 2 cm. Not bad but not perfect. This alignment (right out of the box) was +- 0.2% (equivalently +- 0.1 degree). For my 1200mm focal length scope, the targeting of the center of the primary would be +- 2mm; as reflected back onto the target on the laser (2x focal length): +- 4mm. (It could be adjusted better than that if I wanted to, but see below.) While googling to see if that alignment would be sufficient, I came across the Barlowed laser method. I tried it, and it works GREAT! I was very happy. Super easy and convenient! (Assuming your telescope collimation is pretty close, secondary ok, and you just need to fine-tune the primary, which is typically the case with a frequently-used and unabused Newtonian....) 1. Put the laser in a 2x Barlow. 2. Put the Barlow in your focuser. 3. Turn on the laser, using a fairly bright setting. 4. Observe the shadow of the primary mirror’s center marker “donut” in the target area of the laser. 5. If the donut is already centered on the target, you’re done. Mine was about 1/4” off. 6. Loosen the lock screws on the primary. 7. Adjust the primary, turning one screw at a time to see where the donut shadow moves on the target. (You can see the target while at the primary end, so you don’t have to move back and forth between the primary end and the focuser like you would with a Cheshire or collimator cap.) 7. When the donut shadow is centered on the target, tighten the lock screws, and you’re done. Quick and easy. Love the Barlowed laser method. Note: unlike with the direct laser method, the Barlowed laser method is insensitive to small laser collimation and positioning errors. So this works even with the laser alignment a little off.

Outstanding. Easy to use. Tried collimating with a Cheshire unit with no luck The laser made a significant difference and indicated where the mirror should be adjusted

Was gifted an old Celestron Comet Catcher from the 80s and the images were super blurry. The "Youtubes" suggested collimation and 15 minutes later, it's like a new telescope! Easy to use with several brightness settings and as a plus, it comes with a 2 inch eyepiece adapter

I have had telescopes for years and always used a home made Cheshire Eyepiece for initial collimation and then an out of focus star to "tweak" that last tiny adjustments. When I saw the price of this laser collimation tool I decided to give it a try after reading a few reviews. The one I received was spot on collimated and required no fiddling with correcting the aim of the thing. It worked as expected and the variable brightness of the laser was a useful feature. As far as the "Collimate in Minutes" goes, yes, you can complete the process if your scope is not too far out of adjustment, but if you have had the mirrors out and replaced them it will take a little longer time. A center dot on the primary mirror is needed and easy to do. Several YouTube videos on adding the dot and using this Collimator. The only issue I have with it is the switch is sketchy. As you turn it the laser will come on at the brightness I desire but then it goes off. If I wiggle the switch it will come back on and stay on. I thought I may return it as defective but since it was shipped collimated correctly I do not want to take a chance of exchanging it for another one. I will just wiggle the switch. I will still use a star for the final tweaking but this Collimator is an excellent starting point. 4 Stars Overall

How to collimate a Newtonian reflector telescope Some telescopes come with a simple collimation aid that amounts to a piece of circular cardboard with a pinhole in its exact center, which you insert into the eyepiece. This gadget (or a DIY version of it) will not allow you to get the collimation as precise as it needs to be. The laser collimation tool is very inexpensive and it will enable you to get the collimation perfect. The telescope that I recently purchased and that I needed to collimate is the Sky-Watcher Virtuoso 150. Some minor details of the procedure that I will describe are specific to this telescope, however the procedure applies broadly to all Newtonian reflector telescopes. Collimation of a Newtonian telescope is done in three steps. In step 1, you position the secondary mirror directly under the focuser, so that when you look straight into the focuser, you see the secondary mirror without needing to look “at an angle”. In step 2, you adjust the tilt of the secondary mirror so that it is precisely aimed at the primary mirror. In step 3, you adjust the tilt of the primary mirror so that it is aimed precisely back at the secondary mirror. Make certain that the tube is tilted slightly down in front so that nothing can drop into the tube and land on the primary mirror. The secondary mirror has a base that is permanently attached to the mirror, presumably made of plastic. The base is held to a support (the “spider”) by one center screw and three smaller screws surrounding the center screw. With the Virtuoso 150, the center screw has a Phillips head; the three small screws require a 2mm hexagonal wrench. Be certain to use the correct size of Phillips screwdriver for the center screw. The screwdriver tip needs to fit fully into the cross-slot, but not be able to rock back and forth. The center screw slides freely through the support and is threaded into the mirror base. In the space between the mirror base and the support, there is a spring that pushes forward on the mirror base. The screw moves forward along with the mirror base, and thus remains in contact with the support. Before you will be able to loosen the center screw, you will need to loosen the three small screws. Turn all three of them counterclockwise. With my telescope, I simply turned all three of these screws until the tip of each screw (the end where the hexagonal wrench meets the screw) was roughly flush with the surface. I will first describe a very low-tech method I used to check whether the secondary mirror is directly under the focuser. With one eye covered, position your head about a foot away from the focuser, and with your eye centered in the focuser (without the pinhole gadget in the focuser). If your eye is off-center, the interior wall of the focuser will not look uniform all the way around. With your eye centered, look at the secondary mirror. Ignore what you see in the mirror, and concentrate on the perimeter of the mirror. Its appearance will be that of a circle, and what you want is for this circle to be centered within the circular opening of the focuser. You will need to move your head closer and further until the mirror circle is ever-so-slightly smaller than the circular opening through the focuser. As you move your head forward and back, continue to pay attention to the interior wall of the focuser, to insure that your eye is centered. If you are using the laser tool, set the power only as high as it needs to be for you to see it. You want to check where the laser is hitting the secondary mirror. If you have a collapsible telescope that permits you to see the secondary mirror, you want to identify the spot where the laser directly hits the secondary mirror. If you stick a sheet of paper into the light path between the two mirrors, this will make it easier to tell which laser dot is the one for the direct light from the tool. If your telescope is not collapsible, the best way for you to see where the laser dot lands on the secondary mirror is by using another small mirror. You carefully insert this mirror into the open end of the telescope and hold it wherever you are able to get a good view of the secondary mirror and the red dot. With either of these methods, you want to mostly ignore the centering on the minor axis of the elliptical secondary mirror (the lateral centering). You are concerned almost exclusively with the centering along the major axis of the elliptical secondary mirror. With the Virtuoso 150, I found that the correct position for the secondary mirror was all the way back against the support. But you don’t want to position the mirror right up against the support, because if you do this, you won’t be able to adjust the tilt. Therefore, if your telescope is like mine in this respect, you will want to gently grasp the mirror by the base so that it is rotationally correct (i.e., faces toward the focuser) and then turn the center screw counterclockwise one-quarter to one-half of a turn. Once you are satisfied with the position of the secondary mirror, you want to begin tightening the three small screws, but doing this in small increments so that one of them does not end up being too far in. You want to turn all three of these screws until they are just barely touching the mirror base. If you are using the pinhole gadget, what you want to see, when you look through the pinhole, is whether the reflection of the primary mirror is centered in the secondary mirror. If you are using the laser tool, look down into the open end of the telescope and look to see whether the laser strikes the primary mirror at its center (which is typically marked with a tiny circle). You will likely need to rotate the secondary mirror slightly, and you will likely need to loosen one or more of the three small screws a few times until you get good at this. When you are satisfied with the tilt of the secondary mirror, you’re ready for the final step: the tilt of the primary mirror. I suggest that you start by visually inspecting the gap you see between the back of the telescope and the black metal ring that holds the primary mirror. This gap should not be very great, and it should be roughly constant all the way around. For a small 6” telescope like the Virtuoso 150, it should be only about 1/4”. (Don’t waste time measuring this. Just eyeball it.) To adjust the tilt of the primary mirror, you first loosen the three locking screws, which are the three long, slender screws. The other three screws, the ones that are shorter and not so skinny, are the adjusting screws. You turn them clockwise to pull the edge of the mirror closer and make the gap more narrow near that screw, and you turn them counterclockwise to make the gap wider. When you look into the pinhole (if you are using the pinhole gadget), you will see, working from the perimeter to the center: (i) the perimeter of the secondary mirror; (ii) the image of the primary mirror, reflected off the secondary mirror; (iii) a dark ring; (iv) the image of the secondary mirror, reflected off the primary mirror; (v) the crumpled back surface of the alignment gizmo; (vi) a small dark circle that marks the center of the primary mirror; (vii) the pinhole that you are looking through. What you want is for the image of the pinhole to be centered in that small dark circle. If you are using the laser tool, you want to look at the target mounted within the tool. You want the laser to strike the target at its exact center.

quality item,works great.

Got mine few days ago, couldn't be more happy with the quality and easy of use. Highly recommend

It’s unfortunate that this laser collimation has 2 problems: 1. The laser beam is not collimated, it traces a circle when I rotate it. 2. The diameter of the collimation is slightly smaller than the diameter of the telescope focuser, this size mismatch is enough for the laser collimator to fit slightly differently each time you attach it to the focuser therefore it provides different results each time. Sure you can spend time and fix these defects by collimating and calibrating the laser beam using the screws on the sides and put a layer of tape on the collimator neck to make it fit snugly in the focuser, but when I buy a tool I expect it to perform and function properly right out of the box. I don’t expect to spend additional time and effort to fix the tool to be usable.

Good product, but Its not accurately calliberated out of the box, don't get me wrong, its just off by very small degree. Most of the time you can get away with that small degree of caliberation error. Highly recommended if you are using it for purely visual.

Es excelente para colimar mi telescopio con mejor precisión.

When you get yours you’ll need to collimate it first, check online for videos of how to collimate a laser collimator. Once that’s done the process is fairly simple and quick. It’s also easy to do a quick re check before using your scope. Edit: I can’t believe some of the negative comments. I would think everyone would know that you have to collimate a collimator. Collimating this one is as easy as any other. There are 3 holes on the collimator, all are filled with a gel from the factory. Removing the gel is the hardest part, not actually hard unless you have no hands. Once gel is removed, there are 3 small alen screws that need to be fiddled with to collimate, 'align,' it. This process is a bit finicky but quite simple, videos online show how to do it. For someone to say this is no good cuz they have no idea that it needs collimating or that they don’t know how to do it is ridiculous! I have no affiliation with any company that sells this product, I’m also new to the world of astronomy. If I can figure this out I would think anyone could.