HoTech Advanced CT Laser Collimator
 HoTech Advanced CT Laser CollimatorHoTech Advanced CT Laser Collimator 

HoTech Advanced CT Laser Collimator

  (8 Reviews)
✓ 2 year warranty


1x in stock shipped 1-2 working days

About this product

Model:  hotech_adv_sct-125

The HoTech Advanced CT Laser Collimator (patented) is a breakthrough in Cassegrain Telescope collimation! 

Collimate Your Cassegrain Telescope:

  • Without using a star
  • Indoor or outdoor - day or night
  • Focus stays at final view setting
  • Within focal distance from your telescope
  • One-man operation
  • Portable and simple to setup and use
  • Works on CT, SCT, SN Mak, & RC




BBC Sky at Night Magazine Review 2014 Nov. Issue
Advanced CT Laser Collimator by Astronomer Paul Money.
An honor to be a Five Star Rating of this revolutionary laser collimator.



Advanced CT Laser Collimator review from Astronomy Magazine
by Amateur Astronomer Tom Trusock.
"The collimator did a consistently good job of aligning the optics in my scope.  If you or your astronomy club are interested in getting the most out of your SCTs while saving valuable observing time, I recommend checking into this product."

Advanced CT Laser Collimator review from Amateur Astronomy Magazine
by Senior Astrophotographer Robert Reeves.
"The device provides an unparalleled amount of data useful for tuning telescope optics, perform all the checks available, and revives my ailing telescope and transforms it from a near paper wright to a fantastic planetary imaging scope."

Advanced CT Laser Collimator review from Astronomy Technology Today.
by Amateur Astronomer Rod Mollise "Uncle Rod."

Sky & Telescope
"There is a tremendous amount of creativity and cleverness being displayed, all backed by a fervent devotion to making the sky more accessible and enjoyable for astronomy enthusiasts at all levels. It is truly inspiring."
by Robert Naeye, Sky & Telescope Editor in Chief

New developed co-alignment technique for easy collimation with a higher level of accuracy.

"This is a very clever device.  By using three perfectly aligned laser beams it simulates the parallel rays coming from a distant star.  The beams then pass through the telescope twice to amplify any error in the entire system making even small miscollimation errors readily seen and fixed.  David's done his homework on this one, coming up with a very ingenious answer to daytime collimation of an SCT."  Craig Stark, Ph. D. Associate Professor and Founder of Stark Labs & PHD Guiding

Innovation brings affordable and portable Collimation into Reality.

Since the invention of the Cassegrain Telescope in 1672 by the French sculptor Sieur Guillaume Cassegrain, the Cassegrain Telescope has evolved into various derivative designs such as the more popular Ritchey-Chrétien, Dall-Kirkham, Schmidt-Cassegrain, and Maksutov-Cassegrain. The designs have gained their popularity because of their compact and simple to produce design. With different designs, star collimation is and has always been the only effective method to collimate for Cassegrain telescope owners.

Now, backyard astronomers have an alternative to achieve excellent collimation conveniently using the Advanced CT Laser Collimator. The Advanced CT Laser Collimator brings the collimating star to your telescope within arm reaching distance. With its short range capability, you can perform collimation indoors - day or night - without being subjected to weather conditions. And best of all, this new collimator utilizes a clear and simple-to-read, large target display for the telescope alignment diagnostic.  This large target display is positioned within a short focal distance of the telescope which allows you to collimate without guessing.

No Star Required.

In order to achieve an accurate star collimation, normally the amateur astronomer requires good seeing conditions with no cloud, no wind, stable temperature, no light pollution, a well-aligned telescope mount tracking system, telescope optical tube assemble (OTA) thermal equilibrium, and a good visible magnitude star.  The visual quality of the referencing star is greatly affected by the prescribed factors most of which are all in Gods hand as you can see in the photo. Adjusting the collimation is guessing game where you move between front and the back of the telescope adjusting the corresponding alignment screw and holding your breath peeping through a high magnification eyepiece referencing the concentricity of the unstable defocused image.  This can be an incredibly frustrating experience.
An artificial star can never simulate a real star because it is impossible to collimate with the telescope focus set at infinity. After artificial star collimation, you will need to adjust your focus back to infinity to view a real star by moving the primary mirror to a different position. The distance the primary mirror has been adjusted can accumulate mechanical tolerance errors. For some of the mass produced SCTs, the “sticky baffle” on the primary mirror focusing mechanism may also cause mirror-flop. If a mirror-flop has ocurred, it will affect the alignment position which in turn will render the collimation useless. Ideally, It is best to collimate your optics at the same viewing focusing position without major optical displacements to correspond to the final view setting. The Advanced CT Laser Collimator can accomplish this task without all the possible accumulated errors.
The large target display on the Advanced CT Laser Collimator brings you a clear visual cue of three projecting laser dots as the alignment reference at a very comfortable visual distance providing an accurate axial alignment error diagnostic. And during the entire collimation process, no major focusing is needed, thus minimizing the possible accumulated errors from the focusing adjustments. The referencing adjustments are made by bringing the three clearly discernible projected laser dots, projected on the target, into a concentric ring. No more peeping through the eyepiece looking for a changing, ambiguous star image. This alternative collimation method saves precious observing time by collimating the telescope and preparing the viewing programs at dusk or before dawn without the influences of the external environmental conditions.

Collimate Within Focal Distance From Your Telescope.  

The Advanced CT Laser Collimator does not require long focal distances to achieve high-accuracy collimation. Utilizing the installed flat mirror at the focal point (eyepiece location), the collimator lasers double-passes both your primary and secondary mirrors and magnifies the alignment errors to a higher accuracy level. In addition, it also cuts the collimating distance in half achieving near-field alignment process. The collimator is stationed within your telescope's focal length directly in front of your telescope. Setting up for collimation, you will be standing between the telescope and the collimator aiming both the telescope and the collimator at each other. Then you will adjust the secondary mirror knob to bring the returning lasers on the same track. This is a very convenient one-man operation.

At a Fraction of the Cost of Wavefront Interferometer Technology.

The state-of-the-art advanced laser optical alignment technology used in the Advanced CT Laser Collimator achieves the same rough alignment function of a costly large aperture interferometer commonly use in high-energy labs at a fraction of its cost.
The Advanced CT Laser Collimator uses three collimated lasers, evenly spaced apart, to sample large aperture optical elements in your telescope. The three parallel laser beams completely simulate the light path (flat-wavefront) from a distant star and pass through the entire telescope’s optical elements and reflect back to its target for a complete and accurate double-pass diagnostic reading of your telescope optical alignment. This innovative collimation technique and technology enables the amateur astronomer achieving far-field collimation as a near-field process.

Precision CNC Machined Panel and Components.

This beautifully designed instrument is precision machined from a solid block of aero-space grade aluminium. It is then hardened and anodized to keep the entire mounted laser system thermally stable allowing you to achieve accurate collimation. The rigid, ultra thin profile, and light-weight design makes the unit portable and simple to setup and use.
Collimates All CT, SCT, Makustov, & RC Telescopes.

The Advanced CT Laser Collimator simulates a real distant star light path, and as a result it can collimate most telescopes which primarily rely on star collimation. The collimation technique can be implemented on any size telescope. The current production model is designed to collimate telescopes with a primary mirror greater than 7-1/5-inches and a secondary mirror obstruction diameter less than 6-1/2-inches.  For other larger sized telescope, please email or call us for custom sizes.
Package includes:
Advanced CT Laser Collimator
Premium Carrying Case
Fine Adjustment Stage (FAS-01)
Reflector Mirror (please select 2" or 1.25" to suit telescope focuser)
CR123, 3V lithium battery



User Testimonials

Personal testimonials from renowned astrophotographers and users.

Customer reviews

Average Rating (8 Reviews):  
Write a Review and share your opinions!

Rating (max 5):  
25 January 2021  | 

Good price quality

Rating (max 5):  
HoTech Advanced CT Laser Collimator
30 December 2019  | 

I struggled to collimate my CPC 925 after I changed out the collamation screws for Bobs Knobs. After reading the reviews on the HoTech Advanced CT Laser Collimator I took the plunge and bought from First Light Optics as I struggled to get one from Australia. The HoTech collamator is amazing and so easy with just a little fine tuning on a bright star required, very happy!
First Light Optics service was also first class with my package arriving to Perth WA withing 3 days and that was over the Christmas period! In fact, my delivery from FLO arrived quicker than what it would if I had purchased from the East Coast of Australia where I normally buy from. Will definately be buying from FLO again

Rating (max 5):  
This is the best collimator on the market.
23 January 2019  | 

This collimator is expensive but once you see the results it is worth it, I have spent lots of time & money on other collimation products that have not worked, I collimated my RC8 in a few hours and it is the best it has ever been.

Rating (max 5):  
Good but lacks instructions
14 December 2018  | 

I have a Celestron Nexstar Evolution 9.25Ē SCT.
Which was slightly out of Collimation after a year of use and road trips. Being very nervous as I have never collimated a SCT I decided to purchase the the HoTech laser system.
After watching HoTechs YouTube video and a few others I decided to take the plunge.
The YouTube video and the written instructions provided donít not follow the same work flow for a start. The instructions and poor and a black and white photocopy this means you canít easily see where the laser lights should be. So I decided to follow the YouTube video. Half way through it be came apparent this isnít going to be easy after insuring alignment which does get easier (after multiple attempts) you have to align the main mirror to the back focal point on the Nexstar there is no way to adjust the focuser. Long story short... collimatation was way out worse than when I started. I emailed HoTech several times and got no response. However Martin from First Light Optics was on hand to save the day/night. Since I have worked out how to align from the focal point forward as I couldnít find a adjustment adapter that would work with my focuser. I am please to say after multiple attempts over several weeks. The back mirror, secondary mirror and correcting lens all converge to the focal point at the focuser.
This is a good product however the instructions are poor. Also if you donít have the ability to move your focal point at the back then life isnít easy.
Thank you First Light Optics excellent customer care. 💫

Rating (max 5):  
I'd give it 5 stars if the instructions were better
10 September 2018  | 

If you are an SCT user then this is a valuable (if expensive) bit of kit.

I recently aquired an Celestron 8'' CPC for outreach which I supsected was out of collimation. As I also have a 9.25SCT in the obsy and a 127 Mak I decided to take the plunge and buy the Hotech.

It is well engineered, well packed but the instructions are woefully inadequate giveen the price tag. I had to use them with a Youtube video in order to do the collimation. The terminology used often did not relate to the scope and and collimator target. The images used of the target are poor and worse not even the ones for the collimator target provided.

You do need to read the instructions first and then have a practice run without performing adjustments.

It is not a procedure to be rushed and as the instructions say there is more time spent getting the collimator target and the OTA aligned than there is taken to make any tweaks of the collimation screws.

Rating (max 5):  
HoTech Advanced CT Laser Collimator
20 February 2018  | 

This is a great piece of Kit and the only reason for not giving 5 stars is because it is not quite as easy to use as it may appear in HoTech videos. You MUST have a SOLID method of supporting the collimator, an even vaguely dodgy tripod or other type of mount will give you a headache and frustration. I eventually used and got good results with a metal vice clamping their supplied alt/az mount for the collimator plate. And yes they mean it when thay say that both scope and collimator must be sited on solid ground, if your scope like mine is on a telescope pier surrounded by a wooden deck then don't even try to do it with the scope in situ, put the scope on a good mount where both it and the collimator can be located on a solid floor and both can be moved independently without disturbing the other. Apart from that great!

Rating (max 5):  
Perfect tool
09 December 2015  | 

Having tried various methods of collimation this was simplicity itself to use and well worth the money.
From getting out of the case to complete collimation in less than 60 min on an edge HD8 which I messed up fitting bobs knobs to the secondary mirror. one thing is a must before use... read the manual before you start. You will also find hidden in the foam is the laser diffusion tape which you might or might not need.
the process is slightly different from the videos but I can't say how easy it is to use and it can all be done indoors in comfy conditions.

Rating (max 5):  
Great tool
24 September 2014  | 

I bought this product after buying an 8" SCT from ebay that I could not get to collimate (instead of stars being points of light, they were long streaks). With this tool's help and some advice from FLO I diagnosed that the corrector plate was mounted incorrectly and was not the original corrector plate supplied with the scope.

This collimation device is very precise and I am now looking at stars that are nicely focussed pinpoints and shows DSO in remarkable detail for an 8" cat.

So, the collimator - a little fiddly to use (until you get used to it at least). Firstly two criticisms, both of which concern the (otherwise very nice) case. There is no real space in the case for the mount (the bit between the tripod and the collimator) and secondly, at one point, you're instructed to use a piece of tape to defuse a laser beam - if you can't find it, it's hidden away underneath one of the cut out pieces of foam, I only found it by accident when I was finding a way to fit the mount in the case!!!!!!.

The good bits are that it does what it says and remarkably accurately. For me, there's 2 main benefits;

1. You can collimate the device at any time of the day or night in the warmth and comfort of your front room thus saving valuable observing time - why spend time pointing a defocussed telescope at a star fiddling with collimation screws when you could be using the telescope for its intended purpose. It's very easy to see exactly how much effect each little turn of the collimation screw has on the scope.

2. I think it's way more precise than collimating by using a defocussed star.

For anyone that enjoys "playing" with technical toys, you'll love playing with this one!

It's not cheap but it's one of the things I'm most pleased to have purchased.

I don't think it will work on a cat smaller than 7".

Although the YouTube link on the FLO website shows adjustment on various parts of an 11" cat, the manual says the only user adjustable part is the collimation screws (but clearly it will do other stuff if your cat is suitable for it! I'd endorse the video and manual's comment that it's crucial to line the scope up with the collimator really accurately; this stage takes about 75-80% of the time when using the collimator

If you're unsure of the collimation of your cat, then this device is thoroughly recommended.


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