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DESCRIPTION
The NanoStar artificial star source is designed to provide a steady, stable reference for star collimation to be used in lieu of an actual star. This device will allow high-performance collimation without the worry of star drift or seeing conditions. Plus optic abberation testing on all instrument types, glare/flare and baffle performance, and color-spread testing on refractors or various occulars where it is very difficult to locate an appropriate pure white star of sufficient brightness and steadiness.
Atmospheric turbulence is one big problem for this highest accuracy collimation method - a super steady night is very rare. Then clouds come and go. Maybe your telescope drive and alignments aren't holding the hi-mag position so well as you would like. Maybe you don't even use a drive. Add the convenience of adjustments & testing activity in the daytime or approaching evening when you can see all the scope parts, you are ahead of the game, and you now begin to see how frustrating or impossible it actually is to use a real star for this work. This very bright, small point source of light will provide a consistent brightness, and produce beautiful diffraction rings when defocused in any eyepiece.
The Importance of Proper Collimation. Collimation, in its simplest terms, is the alignment of the mirrors or other optical surfaces in the telescope. A telescope that is out of collimation will typically not perform as well as a lesser telescope (25-50% less aperture) that is in collimation. If you put the extra money into a larger telescope, you are not reaping any benefits of it unless the scope is perfectly collimated. Also, no telescope will allow you to reach a crisp focus at the high power end unless collimation is perfect. It is well worth the time and effort.
Test your instruments, and go one-on-one beside buddies simultaneously to examine differences in telescope types, eyepiece and refractor color optimization, and aperture/barlow/focal length effects. These can be used at star parties to provide a star for everyone throughout the night - you will be thanked once they find out what precision collimation can really do for an instrument!
It never moves, so there are no tracking or centering issues to worry about. It is unaffected by atmospheric disturbances so you can get an accurate collimation under any seeing conditions.
The placement of the star depends on the telescope, but certainly no less than the distance you can achieve focus. The further away from the scope, the better until you start loosing contrast in the eyepiece. Indoor use is a possibility, we have done that before, although we do recommend collimation with the scope in the actual observing position so equipment movement is not of concern.
For star tests, see images below. The star test is particularly valuable in three areas of examination: overall correction, surface ripple and the turned edge with regard to Newt's. However, one should understand that while the expanded Fresnel rings should be exactly the same intensity and clarity both inside and outside of focus, the rings inside of focus on a Newtonian reflector will invariably be a little softer than those outside of focus. Refractor rings will be a trifle softer outside of focus. You will be amazed at how many telescopes can not produce rings on both sides of focus. Some can not produce any rings at all.
A word about laser collimators. Sure they're great, we make them too so we should know. With Newtonian reflectors however there is a niggling little problem. The laser is perfect for alignment of the focusers' tip/tilt, the secondarys' roll/pitch/yaw/extension, and the primary center collimation. Its the best way we have found for all that. However, the laser method assumes the mirror center is the true flat apex of the parabloid of revolution that defines the entire mirror surface - it rarely is. So your total primary mirror surface is not then actually 'pointing' its entire dish to the center of the focuser through the secondary mirror like it should - the laser only reflects off a very small spot in the center of the primary. Only a NanoStar can get around that - it uses the entire mirror surface for the critical primary collimation! Its a perfectionist thing, but you bought the telescope... you should always do that final star tweak collimation for the primary as it makes a big difference on Newtonians/Dobs f8 or less... as any pro already has found.
Feedback: "Please feel free to use me as a reference for this product. The airy disc is amazingly sharp as compared to a star seen through my night skies. I will recommend this product to anyone for you. -J. Wilcox"
"Amazingly sharp airy-disk is what most users never see! Refractor owners will also be blown-away as I was when examining RGB color splits from the center to edge-of-field, rarely possible with an actual star, cake for Nanostar, and critical for color collimation on todays high-performance refractors. -D. Masters"
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