Primary and Secondary Mirror Collimation

The telescope mirror alignment is already adjusted at the factory, so in theory your telescope should be ready to go, however you might find like I did that due to vibrations during transportation, either the Secondary or Primary mirrors need adjustment to bring them back into line.

The Instruction Manual provides good detail and instructions for the collimation procedure, and you should read, practice and master the process. In due course I will be preparing my own thoughts and tips page on collimating the scope.

The viewing image can be greatly affected by even a small alignment error (because the XT10 is a "fast" scope with an f/4.7 focal ratio), and so it should be checked before each viewing session.

In fact some XT owners report that they even check and re-collimate once or twice during a single evening's viewing session! Personally I think this seems a little excessive, and if the primary mirror goes out of alignment during a viewing session this suggests that perhaps there is movement in one of the mirror mounts (Primary or Secondary), and the mirror mount screws should be double-checked to ensure they are holding the mirrors securely, but without applying so much pressure as to "pinch" the mirror which could introduce other distortions.

Certainly a small shift in alignment can be expected after transporting the telescope in a vehicle, but there should be very little if any movement simply due to smooth movements of the telescope in normal use.

Your new telescope is now ready for its "first light". Good luck I hope you have some nice clear nights to get started.

Anyway, here's a couple of pictures to whet your appetite (click the photos for larger images).

Pentax Optio L30The first two photos shown here of the Moon were taken very soon after I first got my XT10. It's dead easy!

I was just enjoying showing my neighbour the view of the Moon. We used just the standard 25mm eyepiece, plus a 2xBarlow for the close-ups. The digital camera I used is a Pentax Optio L30 which is a simple point and shoot.

I'd had a couple of whisky's so I wasn't being particularly careful or bothered about settings, it was really just a case of "try it and see what we get". This was just holding the camera against the eyepiece (afocally), letting it focus automatically, and using some zoom to get closer in. Obviously there were quite a few duff shots, but also some quite impressive ones too.

I'm quite pleased with the results for my first attempt!


Moon Close upI love the atmosphere of this shot (or lack of it, joke!). Seeing the shape and texture of the craters close up really impresses upon you the size and roughness of the Moons' surface.

You can see more Moon photos in the Astrophotography section of my site.








SaturnThis third shot is of course Saturn. I will never forget the first time I looked at Saturn. Through the 25mm alone, to the naked eye it appears quite small. Using the Barlow, and then the 10mm brings its size much nearer (now at 240x magnification), but I remember being astounded by the fact I could see not only the planet and its distinctive rings, but also Saturns moons, like little stars huddled around it. That was awesome, and made me realise I wanted to get a better eyepiece offering higher magnification.

This shot was taken a few weeks after I got my scope, after buying a Philips SPC900NC Webcam from EBay.

I used it to take an AVI movie simply by aligning Saturn at the leading edge of the field of view, then leaving the scope static, and just letting Saturn traverse the field of view (which takes about 30 seconds). Afterwards I then used K3CCDTools which is a piece of software that will gather the best frames of the movie, enhances, aligns and stacks them all together, to make one composite picture, and this is the result.

Again its early days for me, but pleasing nonetheless to have taken the movie and then got to grips with the software, and it shows reasonable results can be obtained without motorised equatorial tracking! I might add that the sky was not particularly bright or clear on that evening either.

You can see more Saturn photos in the Astrophotography section of my site.

That completes this Assembly section of my web site, but the next section is the one on Collimation Techniques.

Other Topics in the Assembly section: