Telescope Laser Collimator 1.25inch, Bysameyee Calibrator with 2’’ Adapter for Newtonian Reflector Telescope Collimation

Not perfectly aligned but good enough. I couldn't improve it but I may try again when I have time and a little more patience.

Have to say when the supplier read my original review they have been great: Contacted me to check the problem, and have sent a replacement. This worked perfectly, self-aligned out of the box, and then very easy to use on the Dobsonian. Now I have a crisp focussed view of the sky. Cannot fault the service or the new kit - supplier notes they have upgraded their supplier since I purchased the original. Therefore I changed the review to 5* Thanks Bysameyee (ORIGINAL REVIEW: Although well known that a collimator needs first for it to be collimated itself, this is a poor bit of kit. Rigged up a 90 degree bracket to allow rotation on a distant wall. Alignment grub screws fiddly to adjust. Worst of all the spot is more like a long line, so which end (or middle) do you take to be the centre of rotation?)

The TL,DR; is that this can be a fine tool but check the collimation of the device from the factory before relying on it to collimate your newtonian/dobsonian scope. So when I first bought this device, I thought the collimation was reasonable out of the box and used it to collimate my son's skywatcher 200p with reasonable results but at the time I didn't rotate the collimator in the focuser. However, when went back to do another collimation, this time I did rotate the collimator in the focuser/adaptor and it revealed that it was not concentric with the focuser and therefore it's apparent good results were called into question. I should point out that the supplied 1.25/2" converter has a quite a bit of wiggle in the fitment between both the collimator and the adaptor and also between the adaptor and my focuser. For my second attempt I reverted to using the supplied 1.25/2" adaptor which came with our scope which had a more concentric alignment. This still needed the collimator to be shimmed with a few wraps of aluminium foil to take up the slop between the collimator and the adaptor to ensure it had a wiggle free fit. These two steps dramatically reduced the apparent collimation error when rotating the collimator in the focuser but didn't completely eliminate it. What did the trick was to identify that the collimator needed to be adjusted as the factory collimation was slightly off. The screws are hidden, buried in black silicone rubber and there are three, including one under the laser warning label. I used a #10 scalpel to cut and then scrape the stuff out and then used a 2mm hex key to make the adjustments. An exacto knife would do the same job but be careful when prying out the silicone as these knives/scalpels are brittle and can snap off sometimes with alarming results. I then made a makeshift cradle with four nails at approximate right angles nailed into a spare piece of wood and a fifth to prevent the collimator moving backwards (see first picture attached). I then gaffer taped the cradle to the kitchen worktop to prevent any extraneous movement and then aimed the collimator laser at the back of the kitchen wall some 4 metres distance. I had printed out a target (just some concentric circles on an A4 piece of paper - second piture) which I approximated the position of the laser to be central in the circles then started to rotate. By making small adjustments to the now uncovered screws, the position of the laser can be adjusted so that it's range of motion of the laser dot when the collimator is rotated 360 degrees should be able to be reduced to near zero. This is very much a trial and error effort and patience is required. I finally moved the paper to have the dot be central after adjusting to reduce the apparent movement to be close to zero and tried again to confirm the laser did not move when the collimator was rotated. I think my measured variance is now under 2.5mm at 4m which is more than good enough for me. Job done. For anyone following and making a cradle, use thicker nails than I ended up with. My first attempt with 4 inch round nails split my board and the second attempt with long panel pins had a little too much compliance and needed very careful movement to avoid introducing an error by bending them.

I bought this for £30 which compared to other laser collimators is cheap. With this in mind to get 5 stars I asked 2 questions. 1. Does it produce a laser? 2. Can I collimate it? The answer to both is a yes and whats more you have 8 different levels of brightness that you can use. Like others have found this laser was not collimated when it arrived. To be fair I wouldn't expect it to be. If you are not willing to collimate this yourself then don't buy any laser collimator. In fact I would say go one step further and say buy a refractor because maybe collimation in general is not for you. It is a fiddly job getting this right and you will need to make a "Jig" but there is plenty of advice online with YouTube videos telling you what to do. You will need a x2 Barlow, a Cheshire collimator and maybe a collimation eyepiece to complement this product. Another point people have made is that the collimation screws are covered and you have to dig them out. I must admit this is a negative and I would have given less than 5 stars should the price have been any higher than it is. Do your homework and know what you are getting into before buying. Unless the laser doesn't work or the collimation screws are broke you have nothing to complain about.

Just a quick note to those maybe deciding on a laser collimator. I ordered this collimator and it duly arrived this morning. I popped it on my engineers V block to test if it was true and it was bob on. No deflection in the light spot as I rotated it. I have been collimating my Dob with a cheshire and thought I was pretty accurate with it !! doh, nope. Fitting the laser I could see that It was out by quite a lot! Not sure how much ' out by quite a lot' affects viewing experience though. 😂 I adjusted both the secondary and primary within a couple of minutes. So easy !! The acid test of course is when we have a clear spot enough to look at something but I see no reason why it would not do the job as advertised ! As with all laser collimators, you must check that the laser light is sat square in the housing and not deflecting the light as it exits. An easy way to do this is to set the collimator in a V shape and point the laser at a wall. Slowly rotate the collimator. If the laser wanders off it will need adjusting. If it stays in the same spot its in line. I would recommend this.

Easy to use with near perfect collimation. I am a beginner with astrophotography so this was a no brainer - there is a branded identical version of this so save some pennies and buy this one.

This is a very good piece of equipment. I have had my telescope for a few years now and decided it was time to check it's collimation. This device has helped do this, I like that it has 8 light settings 0-7 zero being off. This means that if you want to check collimation in the dark it doesn't blind you and in bright sun light. Excellent piece of kit.

I have been tempted by these for a while. But have been put off by the need to collimate the laser. When the package arrived, the inner blue packaging was broken like it had been dropped. The outer box and packaging was OK though. I am not sure how this happened. When I tested the laser on a 90 degree rig it was out of collimation from the factory and the dot was more like a small line, so this is unusable which is disappointing and I will be returning the item.