Review on SVBONY Red Laser Collimator: Perfect Alignment for your Newtonian Marca Telescope by Marcelo Montalvo

Good range of brightness levels. Came fairly collimated (adjustable). Works great with Barload's laser technology. Really simple and effective! Brightness: Fairly dim on the lowest setting to fairly bright at 4 or 5. Collimation/alignment of the laser itself. I assembled the jig using Lego (great suggestion I read online), set it on a granite countertop (glue the jig on the worktop to keep it from moving) and aimed at the wall at a distance of 6 meters. The diameter of the circle drawn on the wall when rotating the laser on the lamp was 2 cm, not bad but not perfect. This alignment (right out of the box) was +-0.2% (equivalent to +-0.1 degrees). On my 1200mm focal length scope, aiming at the center of the main element is +- 2mm; when reflected to the target on a laser (double the focal length): + - 4 mm. (It could be adjusted better if desired, but see below.) While googling whether this alignment would be sufficient, I came across Barload's laser method. I tried this and it works GREAT! I was very pleased. Super easy and convenient! (Assuming your scope collimation is pretty close, the secondary is fine and you only need to fine tune the primary, which is usually the case with the commonly used and unused Newtons.) 1. Place the laser at 2x Barlow.2. Place the barlow in your focuser.3. Turn on the laser with a fairly bright setting.4. Observe the shadow of the mark in the center of the main mirror "donut" in the laser's target area.5. If the donut is already in the center of the target, you're done. Mine was about 1/4 inch too small.6. Loosen the set screws on the primary winding.7. Adjust the primary side by turning one screw at a time to see where the donut's shadow moves on the target. (You can see the target from the primary end, so you don't have to move back and forth between the primary end and the focuser as if you were using a Cheshire or collimator cap.) 7. When the donut shadow is in the center of the target, tighten the locking screws, done. Fast and easy. I like Barload's laser method. Note: Unlike the direct laser method, the barload laser method is insensitive to small errors in laser collimation and positioning. So it works even if the laser alignment is turned off a bit.