Hotech SCA Laser collimator

[FenlandPaul]

OK, so this is only half a review really as I've not been able to see a star since using this collimator for the first time.  But I'll update on that side of the performance once the UK emerges from the current dose of cloud cover.

I ordered a Hotech SCA laser collimator from First Light Optics, who had it in stock and it arrived 2 days later.  I chose this collimator as I ahve always struggled with my Cheshire; not having arms like Mr Tickle and being of less-than-average intelligence, I found the collimation guides completely baffling in practice.  I'm not sure I've ever really cracked it, and the propsect of trying successfully in the dark was just not realistic.  So a conversation with someone from this forum led me to think a laser was the best option, vwith collimation then taking place at the primary-end rather than scooting between eyepiece and primary and getting all confused and frustrated.  Please don't laugh at me...

The Hotech seemed to get good reviews for its simplicity, the high level of out-of-the-box collimation, and the fact that it is self-centering.  So I went for it even though there are plenty of much cheaper options around (and a handful of more expensive options).

The Hotech comes in a rather nice, solid presentation case - the sort you might expect a nice pair of cufflinks or a fancy watch to arrive in.  Come to think of it that would have to be one large pair of cufflinks.  The battery is in the box separate to the collimator itself, presumably to ensure it doesn't leak or discharge in transit.  That's just as well as the chances of finding one of these curious batteries at your local Poundland is minimal.  I imagine it's an online-purchase job.

The instructions that come with the collimator are really clearly laid out.  Installing the collimator in the focusser was dead easy, and the integral compression rings really hold it fast.  I wiggled the laser after it was clamped and the dot hardly budged at all on the primary.  

First of all you look (carefully!) down the tube and use the secondary collimation screws to get the red dot centered on the primary mirror, right in the centre of the ring that came on my primary mirror when I bought the scope.  Not sure what you'd do if you didn't have a centre-dot on your primary.  This was pleasantly easy.  In fact, the Hotech comes with a red dot overlaid on which is a cross-hair, so when you have the dot centred in the primary "donut" sticker you can see 4 dots overlaying the donut, which is the crosshairs intersecting the donut.  This is useful to show that you have it bang on centre.

Once that's done, you head to the primary mirror and tweak collimation until you see the red dot and cross-hairs appear in the viewing window of the collimator.  My scope was horrendously out of collimation as I recently had the mirror cell out to drill some holes in the tube, so initially I couldn't see a dot at all.  After a while of experimenting I saw a whisper of one of the cross hairs, but I had to keep experimenting until I could see a very defined dot appear.  Once that was visible, it was reasonably straightforward to get it centered.

I was pleased at how easy the process is - much easier in my view than with a Cheshire, but I know there are people on this forum for whom using a cheshire is like riding a bike, and is second nature.  I'm not one of those people.  I can genuinely envisage using this every time I set up to check collimation, and this undoubtedly will improve the quality of my sessions.  I'm looking forward to that.

So I know the proof of the pudding will be in using this under the stars, but first signs are good and I'll post an update once I've got the scope out under the stars.

Paul

[mapstar]

I've always found the Hotech easy to use

 Looking forward to reading about the views after your collimation improvements 

[Peje]

This is exactly the information I needed, I've been collimating using the cheshire and while I have been able to get it done I was never sure how accurate it was as to me it seemed like to much was down to my eye's judgement...and being a glasses wearer this is a bit of a fudge for me.

Tonight I popped the primary cell out so I can make a tempate in work tomorrow to let me put a centre donut on my scope. My scope is nearly 20 years old so it didn't come with a mark, or indeed some other adjustment options that seems standard these days.

I'll be upgrading to a SW Quattro next summer so I figured getting proficient at collimation is going to be a must for me having an f/4 scope, as you explain the process it seems it's going to be extremely simple to check my collimation at the beginning of each session and perhaps more often if required.

[FenlandPaul]

On 20 July 2016 at 21:50, Peje said:

This is exactly the information I needed, I've been collimating using the cheshire and while I have been able to get it done I was never sure how accurate it was as to me it seemed like to much was down to my eye's judgement...and being a glasses wearer this is a bit of a fudge for me.

Tonight I popped the primary cell out so I can make a tempate in work tomorrow to let me put a centre donut on my scope. My scope is nearly 20 years old so it didn't come with a mark, or indeed some other adjustment options that seems standard these days.

I'll be upgrading to a SW Quattro next summer so I figured getting proficient at collimation is going to be a must for me having an f/4 scope, as you explain the process it seems it's going to be extremely simple to check my collimation at the beginning of each session and perhaps more often if required.

Certainly if you get the donut centred well I think you'll find the Hotech simple and effective.  Unfortunately since I wrote this review I've only managed late evening viewing in very sloppy seeing, so haven't yet really put collimation to the test.  All the best with your upgrades.

Best

Paul

[Peje]

38 minutes ago, FenlandPaul said:

Certainly if you get the donut centred well I think you'll find the Hotech simple and effective.  Unfortunately since I wrote this review I've only managed late evening viewing in very sloppy seeing, so haven't yet really put collimation to the test.  All the best with your upgrades.

Best

Paul

I managed to centre spot the primary last week without much trouble using a homemade template, the laser arrived on Friday so I spent about 45 mins getting the focuser centred/aligned wrt the secondary. I had originally planned to stop at this point and use the laser the follwing night but impateince got the better of me...ten mins later the primary and secondary were done

I plan to redo them to get more practise doing the iterative work but the Hotech collimator has made a huge difference to my confidence and drastically reduced the amount of time I need to collimate.