Just remember… you are almost never standing upright as an astrophotographer anyway. If the star drifts DOWN you want to rotate the mount to make the star move to the LEFT. If the star moves UP you want to rotate the mount’s azimuth to make the star move to the RIGHT in your field of view. The azimuth adjustment is maddening because as you note the star drifting in declination, you rotate the mount in azimuth to shift the star PERPENDICULAR to the direction it just drifted. Once you note some declination drift while watching a star near the celestial equator and meridian, you are seeing errors in AZIMUTH, or East/West. Your mount may be pointing too far east or West of the Celestial Pole. Sky, and would be directly over your head if you lived at the equator!ĪziMuth is MAD!: Now it's time to make the adjustments to correct your Polar Misalignment in AZIMUTH. The imaginary extension of our equator if you extend it out into the Line that runs East to West, 90 degrees from the celestial poles. The CELESTIAL EQUATOR is zero degrees Declination. The MERIDIAN is the imaginary line that runs from the Northern horizon,Īcross directly overhead, and then down to the Southern horizon. To begin, you need to locate a star near the intersection of the Now move the star to one side and rotate the eyepiece until the star glides along the lines when you move the scope's RA axis (click on the curved arrow in the animation to the left) Most likely your eyepiece is not orientated properly, so the star will not line up with the reticle lines. As you move the telescope in RA forwards and back (using the hand controller) you will see the star glide left and right. Even at the lowest setting, these things are a bit bright!). First, locate a bright guidestar and watch it in your illuminated reticle eyepiece (you may find it easier to switch the illuminated reticle off, find a star, then switch it back on. This step may be confusing, but it really is a simple step. STEP THREE: Aligning the Reticle: During each step below, you need to make sure your Illuminated Reticle Eyepiece lines are lined up with the East/West axis of your mount. :) Oh, and by the way, you'll need an Illuminated Reticle Eyepiece (who said this hobby was cheap?!) Please note that this is all © Peter Kennett, including the Flash content - I do not claim credit for any of what follows :) I have added the occasional comment within the text, perhaps where I think things could be explained slightly better - all such comments are in red.īecause this content may be something that viewers may want to return to, I've made it a page instead of a simple blog entry. He has kindly agreed to this, and the result is below. I was concerned that the information may be lost forever as the website is no longer maintained, so I got Peter's permission to reproduce the entire content, including a rather nifty simulator, on this blog. And, as they say, I've never looked back! ) Now the stuff on Peter's website on drift alignment is nothing short of brilliant in my humble opinion, and gave me the confidence to give it a go. This is because the website is no longer maintained (Peter now works abroad apparently, and doesn't get the opportunity). You may also notice that most of the links in the left hand margin don't work. Peter's website is here,(edit: sadly, not any more) and the first thing you'll notice is that it uses frames - not good (sorry Peter!). I read everything I could on polar alignment when I started this infernal activity, and dismissed drift alignment as "too laborious", until I read a webpage by Peter Kennett. But bear with it, and it will repay the effort you put in. I'm also the first to admit that, initially, it can be difficult to get the hang of it. I am a firm advocate of drift alignment, mainly because I use it with some success. Drift alignment, however, works regardless of the quality of the mount, but is considered by some to be a bit of a "black art". Using a polar scope is fine up to a point, but it's not particularly accurate, unless you're using a top-end mount.
Without a good polar alignment you'll certainly have sausage shaped stars which you may be happy to accept initially, but eventually you'll want to do something about it. This is particularly important if you're not guiding.
If you want to take good astro images, your polar alignment needs to be pretty well spot on. THE FLASH MOVIES EMBEDDED IN THIS PAGE MAY TAKE A WHILE TO LOAD GUYS - BEAR WITH IT :)
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