Hotech SCA Laser Collimator for Newtonian & SCT Telescopes - 1.25"/ 2"

Hotech SCA Laser Collimator for Newtonian & SCT Telescopes - 1.25"/ 2"
Item # HT-SCA2
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  • The Hotech SCA Laser Collimator comes with an innovative "Self-Centering Adapter" that automatically centers the laser and keeps it from that way to maintain precision.
  • Perfect for Newtonians and SCT's with either 2" or 1.25" focusers, this model comes with 2"-to-1.25" SCA Adapter.
  • The Hotech SCA Laser Collimator is constructed of lightweight, aerospace grade aluminum, and comes with a 45 faceplate viewer and laser-etched target grid.
  • Complimentary CR123, 3V battery included.


HoTech SCA Laser Collimator for Newtonian & SCT Telescopes

The HoTech SCA Laser Collimator separates itself from all the other laser collimators with its innovative self-centering adapter technology (SCA). The mechanism allows precise and repeatable installation in all brands of 1.25" and 2" telescope focusers. All laser collimators in the current market have one fundamental problem - the slop in the adapting mechanism between the laser collimator and the telescope focuser. This problem is clearly recognized and often discussed among astronomers but so far there is no definite solution in the market.

No matter how tight the tolerances machined on the laser collimator or focuser are, a small gap is required to allow installation of the laser collimator. Once the laser collimator is inserted, the required gap becomes a problem. The laser collimator is fixed either with one or more thumbscrews or an unified compression ring. Both methods introduce a very critical issue, namely an off-axis installment that instantly destroys the precision of your collimation instrument along the entire optical axis.

The Self-Centering Adapter cleverly eliminates this problem by linearly compressing the built-in rubber rings. By doing this, the diameter of the rings expands to compensate the gap. Because all rings evenly expand radially in diameter from the compression, this automatically centers the laser collimator in the focuser draw tube. The SCA adapter accommodates various brands of adapting focusers which have slightly different manufacturing inside diameters, so the Hotech laser collimator will be precisely centered for each installment.

The Hotech SCA adapter serves three critical functions.First, its expansion rings accommodate almost all focuser's manufacturing tolerances. Second, it automatically centers the adapting laser. Third, it provides at least two evenly distributed circular contacts on the focuser's inner tube surface preventing the adapting laser from pivoting. Once the slop factor is taken away, you can quickly collimate your telescope in confidence to achieve perfect collimation every time.

HoTech SCA Laser Collimator Extra Features...

Precision Machined Compact Lightweight Design:

Many laser collimator manufacturers give users the wrong impression, that “big and heavy" means "rugged and stable.” Instead, HoTech engineers successfully cut the unnecessary weight from the SCA laser collimator because they understand that additional weight on a telescope (especially open structure Newtonians) will create imbalance and structure sagging. In addition, the heavier the device is, the more inertia it will have during an impact from an accidental drop. In such an accident, the inertia force can cause more damage to the internal alignment mechanism because there is more energy required to dissipate from the impact. The lightweight design on the Hotech SCA laser collimator helps insure that you get reliable precision collimation every time. The HoTech SCA Laser Collimator is made from aero-space grade lightweight aluminum material and CNC machined with the tightest tolerances, then sand blasted and anodized to protect if from harsh environments.

45º Faceplate Viewer with Laser Engraved Targeting Grid:

The faceplate viewer of the HoTech SCA Laser Collimator helps to display the returning laser spot with a clear visual reference during adjustment. The faceplate allows you to align your primary mirror from the rear of the telescope, eliminating traveling to the front of your scope repeatedly during collimation. HoTech understands the importance of this, so the faceplate is a standard feature in their laser collimator.

In addition, the faceplate viewer’s pattern is laser engraved to ensure a long lasting, sharp targeting grid. Unlike other collimators, the target is not a sticker that will peel, or paint that can rub off or chip. You are paying for a precision instrument that is supposed to be well made, and with HoTech, that's what you get!

Finest Projecting Laser Dot:

Keeping the laser dot to the finest point is the key to precision collimation. But when you look closely at the laser dot from brand to brand, most laser dots appear large, not really a fine point as you imagined. This means there is guess work involved when you try to center the dot; not just centering the laser dot to the center of the faceplate, but also centering the center of the dot itself. This does not make any sense when you are trying to take advantage of a collimated laser beam "which has a low beam divergence, so that the beam radius does not undergo significant changes within moderate propagation distances." In other words, the laser beam size within the collimation distance (laser collimator to the primary mirror and back to the faceplate) should remain a constant, fine point.

As you know, most companies that sell laser collimators are not really laser manufacturers. They install an off-the-shelf laser module or pointer and align the laser in a tube without REALLY considering the user’s application, namely the operating distance for a laser beam size. HoTech has been designing and building laser modules and systems for over 10 years for various professional industries. We know exactly how a laser should work. We limit our laser beam to the finest size in the correct operating distance for optimal effect. Our understanding and experiences with the laser design permit you to have an effective and precision collimation.

High Accuracy Laser Alignment:

The SCA laser collimator is well centered and aligned, which are critical factors for an accurate collimation. Unfortunately, you will be surprised that many laser collimators in the market fail in this regard. The reason is in the design and understanding of the product itself.

Hotech considered all aspect of parameters in their design. Parameters like the alignment mechanism, mechanical and optical structure of the laser itself, and more are an important part of their design. For instance, some laser collimators actually install an off-the-shelf laser pointer in the casing. It is very cost effective (for the seller), but it inherits numerous problems. In many cases, the laser pointer might not install perfectly centered in the casing due to pointer size variations and the added alignment mechanism. So the laser itself is not positioned on the true alignment point and optical axis. As the result, the laser can never be center-aligned in the enclosure. It is possible to align the laser beam parallel to the optical path but always with an offset along the optical axis. This means the laser beam is off no matter how you center adapt the laser collimator to the focuser. The result of an off-centered laser will introduce astigmatism into your telescope.

Long Lasting Battery Life:

By using the CR123, 3V battery as the laser power source, the Hotech laser collimator has over 65 hours of continuous use battery life time. The included CR123, 3V lithium battery operates well under a typical cold night and it has a 10 year shelf life. This is important in the field because you don't have to worry about changing the tiny hard-to-find cell batteries frequently in the dark like you do with other collimators.

Additional Information

Additional Information

Manufacturer HOTECH
Barrel Size 1.25"/ 2"
For What Telescopes? Multiple Designs
Warranty 1 Year Warranty
Included Items

Included Items

  • Hotech SCA Laser Collimator
  • 2" & 1.25" Adapter
  • Complimentary CR123, 3V battery
  • User Manual
Questions & Answers

Product Questions

How do you use this colimador with an SCT since it has a hole in the primary?
Will this work for a SKY-WATCHER 8" collapsible dobsonian telescope?
does this collimator have adjustment screws to center the laser?
Can you ship this item to Mexico?
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