People may be
surprised to see me review a laser collimator given my well known dislike of
lasers. Generally speaking laser collimators tend not to work well without a
fairly high precision focuser as the focus slop created by most focusers
generally leads to inconsistent results and very often to large amounts of
frustration for the user.
The HOTECH collimator gets over these
problems with a rather ingenious approach which allows the laser to 'self
centre' itself. I was intrigued by this and fortunately I had the opportunity
of having one to test kindly provided by First Light Optics the sole UK
distributor. So would this unit make me want to own a laser collimator ? Lets
see…….
First Impressions
The HOTECH laser
collimator comes in a rather natty box in a kind of black faux crocodile skin.
Inside the box the collimator rests on a die cut foam insert together with its
battery which is an unusual size (CR123 A) but readily available from most
photographic stores.
The whole presentation is extremely slick and oozes
quality. The collimator itself is made from a combination of metal plus
machined high grade acrylic plastic. The overall impression of the unit itself
is one of great quality and precision. This view was only reinforced by use and
the results it showed.
Something to bear in mind is the HOTECH
collimator is a little different to most and so a good read through of the
supplied comprehensive instructions is to be recommended before you play with
it. Sorry guys I know most of you love to play first but on this one I really
suggest reading the book before you play.
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| Above - The
Hotech Self Centering Laser Collimator in its box. |
Self Centering -
How its Done
The unit, rather than rely on the telescope focusers
thumbscrew lock, relies instead on an ingenious mechanism whereby several thick
rubber strips on its nosepiece are compressed into the focuser by a compression
ring on the collimator. These can be seen in the photographs.
The effect is
that the collimator always finds the exact centre of the focuser which provides
very accurate and reliable collimation. Testing showed the laser to be
perfectly collimated to itself straight out of the box.
The laser is bright
and almost completely circular in shape unlike many other laser collimators
which show a rice grain shape and are often inaccurately collimated. There is
no brightness adjustment on the unit which I personally found to be little
loss.
The laser is switched on and off by twisting the end cap of the
battery compartment. If I bought one of these I think I'd be inclined to keep
the battery out of the unit when not in use to prevent accidental switch on and
a flat battery when you least need it.
Testing the Unit
To
test the unit I applied it to my own Sky-Watcher 200 which was already in
collimation using a standard Cheshire to see if the laser would agree with the
Cheshire. Most low cost lasers never do. To my surprise the HOTECH unit showed
a slight variation but was almost spot on. A small tweak of the secondary and
the primary bought the scope to collimation with the laser and a check with the
Cheshire showed perfect collimation.
I then decided to upset the
collimation completely and start from scratch to see if the HOTECH could do the
job. Obviously you still need a sight tube or colicap to align the secondary to
the focuser and check that the secondary is true but beyond that I used the
HOTECH and found on examination with the Cheshire that collimation was always
very close - the small differences would be due to the Cheshire itself and my
eyes rather than any fault in the HOTECH collimator. My own Cheshire is not
nearly so well engineered as the HOTECH product.
One of the neat
features built into the unit is that the laser grid faceplate has three thick
lines marked onto it - these correspond to the primary mirror collimation
screws. With a little practice you can immediately see which screw needs
adjusting. It's a thoughtful touch and furthers the impression that this piece
of equipment has been thought through very well.
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| Above - The
Hotech unit - its well designed and well made. |
The unit will handle both 2" and 1.25" focusers. The
2" nosepiece is held on to the main collimator body using the same self
centring technique that the unit uses to lock itself to a focuser so if you
have a 1.25" focuser you can still take advantage of the units full capability.
I had planned to test the unit in a slightly less sophisticated scope
but unfortunately the scope on loan had to go back before I was ready. As a
result I was only able to test the unit against my own Sky-Watcher 200 but on
that basis I was very pleased with the product.
Conclusion
If you like lasers or are considering getting one then the HOTECH is
indeed worthy of serious consideration. The list price is expected to be around
£120 which I would consider fair for such a high quality product.
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