Tag Archives: polar alignment

Target that Fuzzy!

Published: Oct 18, 2011
Revised: May 11, 2016

If you’re a veteran astroimager please avert your eyes. If you’re new to the sport, please pay attention and realize that the tips I’m going to describe will justifiably annoy the stew out of serious astroimagers and may get you run out of dark sites or banned from private observing parties. And if you are not an astro imager, read on anyway, because the tip will also apply to landscape astrophotographers, too – tip 5, below, that is.

GreenLaserPointerMy tips advocate using a green laser pointer. I have purchased several from various sources and they range in price from $5! to $50. The $5 ones are from overseas sellers and honestly the quality isn’t always a high point, but then a recent $40 purchase from Fry’s Electronics was also a dud. Green laser pointers in the 5 milliwatt (5mW) range are extremely helpful for pointing out the night sky to beginners because the beam can be seen for miles. These lasers CAN BE DANGEROUS so DO NOT POINT at people or aircraft. The beam can be seen in the night sky for up to two miles. Pointing at or near airplanes may result in your arrest and prosecution. Just don’t do it!

Interestingly the $25 laser pointer with the “Star Pattern Kaleidoscope Cap seems to be the same thing as the $29 version without the cap so save yourself $5 by taking the cap off yourself. The best bargain I’ve seen on a good laser pointer lately is on E-Bay. Search for “Military Grade Green Laser (or lazer)” Be sure to get one with a battery and charger… there are different styles.

As I noted, use of green lasers around serious observers or astro imagers will not be looked upon with favor. You may well ruin their observing and imaging and any budding friendship. If you are confronted and forced to divulge who gave you this dangerous and disrespectful advice please remember my name Neil deGrasse Tyson.  🙂

Green lasers are powerful tools – just like those amazing Jedi light sabers in Star Wars. Listen carefully, recruit and use your force wisely.

When Setting up for Polar Alignment

I point a laser through my polar scope. The beam comes out the front and I can immediately tell if I need to make some serious adjustments to my mount orientation – and in which direction.  Since mount alignment is something you generally do in early twilight (as soon as Polaris is visible) the appalled astro imagers may forgive you for using this method when it is not yet dark enough for them to do imaging.


Acquiring Your Target

Finding an object in the sky that cannot be seen with the naked eye, or in the camera viewfinder is greatly aided by a green laser. I check my planisphere (or better yet a more detailed star atlas) to form an idea where in the sky I need to look. For example I may note that my target is equidistant between two bright stars and up a moon diameter. I then sweep that area with binoculars or a finder scope. When light pollution is bad and I can’t easily find the object, I fall back to my trusty Jedi Laser pointer. Here is how:

  1. Shine the laser through the viewfinder of the camera! Wiggling it around will show the area of the sky that is in the camera’s field of view. I can’t guarantee that no damage will result to your camera – a green laser can wipe out pixels if you point it at the sensor – but that theoretically should not be possible because the mirror redirects the viewfinder to the lens and together with the shutter completely covers the sensor. Be sure your optics (e.g. lens) are focused because if not the laser will be attenuated. You may need to use binoculars to confirm that you’re at the right location in the sky.  This method allows two handed single person operation.
  2. If you don’t want to shine the laser through the view finder: I either hold the laser and the binoculars or I have a friend shine a laser in the vicinity where the target should be. The glowing green light makes finding the direction in the binoculars (or a finder scope) so much easier. Once I find the target with the binoculars, I keep the laser steady and lower the binoculars to see exactly where that green beacon is pointing. I repoint my camera/telescope
  3. If I am imaging with a zoom lens, I may start zoomed out. I take a trial photo (short, high ISO) and confirm whether my target is present or not. If I can’t confirm it I may again point the laser (using binoculars) while the next image is being captured. I am hunting for the green beacon with my image – adjusting the camera as needed.
  4. Once I have my target in my shot I can make minor adjustments using the Decl* and RA* on my mount to fix the framing and do not need the laser anymore.
  5. Oh.. and here is a nifty trick, shine the laser through your viewfinder and wiggle it around… it will trace out the boundary of what is in your shot! Even if you are not doing faint object photography that will be a big help.

*Decl and *RA? What?  If these terms are new to you, you might find my Astrophotography 101: Getting Started Without Getting Soaked to be really helpful.  Or join me out in the field (Astro 201).  See the course list. Many of the classes are webinars and can be attended from the convenience of your computer.

Trying to Decide What to Target?

In the Northern Hemisphere, Andromeda (M31) and the Orion Nebula (M42, or NGC 1976) with its many nearby nebula such as the Horsehead, Running Man, and others should not be passed up. Both are easily spotted with binoculars or even the naked eye in dark sky sites. Don’t expect any of these to give up its glorious color and structure unless you use long exposures and a good camera.

For a great list, see 111 of the brightest deep sky objects article in Sky and Telescope.

If you want to learn to locate objects in the night sky, set up, balance and polar align your mount, and get a start on astro imaging, please consider attending my Astrophotography 101 Webinar and/or Astrophotography 201 Field Practice. If you want to go whole hog on perfecting your astro images, then Astrophotography 301 is what you want!

Again, DO NOT target anything that appears to be moving at all.


Resources for Astrophotography

Original Publication: Oct 12, 2011
Last Revised: Nov 9, 2017

Local Stores (San Francisco Bay Area)

Orion Telescope Center

10555 S De Anza Blvd
Ste 105; Cupertino, CA 95014
(408) 255-8770

Mon-Sat 10 am – 5:30 pm
Sun 12 pm – 5 pm

Equipment Recommendations

There is a lot of gear out there and a lot of thought about what is good / better / best.  For the purpose of my recommendations I’m assuming your interest is primarily Astrophotography and primarily based around using a telephoto lens or a small/lightweight telescope attached to a DSLR. Of course you might succumb to a small telescope. Most of my recommendations are based on personal experience. Some are based on observations of people much wiser than me.  If you decide to get a mount, here are representative alternatives.


Before we dive into conventional mounts, however, lets take a look a well featured, light-weight solutions.

Approach A: Good, Light and Portable


AstroTrac TT320X-AG – photo from AstroTrac site.

Since, portable, inexpensive and stable do not all fit into the same category the best solution is the AstroTrac. It is light, well made and moderately priced (from $546 to $1,959 depending on the package – not including shipping). You will be limited to using the AstroTrac with a telephoto lens on a camera unless you buy some dubious additions to turn the AstroTrac into a big scale solution – but since you’re reading this that is probably what you intended anyway. Be sure to get the Polar Scope as it is difficult to align without it! This mount will track at Lunar, Sidereal or Solar rate!  While $546 might sound expensive, for the light weight versatility it’s hard to beat. For a video and more information, see the manufacturer’s page.

Pros: Total schlep weight (tripod, heads, polar scope, battery, AstroTrac) is about 12 pounds (less if you have a lighter tripod); setup is pretty easy; accurate tracking;  maximum load is 33 pound; stops automatically to prevent damage.

Cons: Limited weight; repointing at a different object may compromise the alignment;  2 hours tracking before reset; single drive solution.

Orion Astrophotography Bundle

A possible solution – much cheaper at $180 but also with very significant limitations is the Orion Astrophotography Bundle.  It is a light weight, low load mount with a single axis drive and no alignment scope. At 14 pounds assembled and a load of up to 7 pounds it’s not bad for very wide field astrophotography – but it will never take more than a single camera load. I DO NOT recommend it. For why, please see my review.


Another product that has caught my eye is the Polarie device.  Imagine a device about the size of  a DVD slip case only about 3 times as thick.

Polarie Device with Polar scope (image from Amazon) – requires TWO heads and a tripod.

The Polarie device costs about $400 USD, but that doesn’t include the possibly unnecessary polar scope – which is an extra $250 – or a tripod rig to set it all on.  Like the Astrotrac, Polarie is light and portable and runs on conventional batteries.  A competitor is the iOptron Skytracker. Very similar features to the Polarie with a few advantages and disadvantages. The Polarie is a miss, mostly in that the scope is expensive, and requires removing the whole face. Once you put camera gear on it, the distribution of weight changes enough that the alignment via the scope is useless.  It didn’t do a good job managing my Canon 50d with a 70-200 mm lens.

iOptron Sky Tracker

iOptronSkyTracker (requires head, tripod)

Of the Polarie and the $400 Sky Tracker, I prefer the Sky Tracker. It’s better thought out.  The down side is you’ll need to remove the head from your tripod and put this in it’s place then put the head from the tripod on the face of the Sky Tracker.

The faceplate only “locks down” via that single screw. I found it sometimes slips. Also there is a little slop in the gearing. The good news is that unlike the Polarie with its expensive polar scope, you can actually mount your camera ON the face and make sure there is room to also use the scope to accurately position things.

There is a newer Sky Tracker Pro available which is more like a “real mount”. Haven’t investigated that much.

The advantage of the SkyTracker over most solutions is that it is light and easily portable.

A Canon 50d with a 70-200mm lens was more than it could manage well.


iOptron Sky Tracker Pro

We have no experience with this unit, however one of our workshop participants managed to make it work well. iOptron Sky Tracker Pro (no experience)



There is even a new contender rising in the KickStarter arena… it’s called Astro: Time-Lapse Motion Control.  It’s not clear if it will be accurate enough to track at sidereal rate, but I am hopeful.

It’s not designed for astrophotography, but if the rate can be set precisely enough, and a simple alignment done it may work quite well.  It does have a built-in intervalometer, though and as you can see it’s quite compact.

NOTE: I purchased one and found it disappointing.


Approach B: Good, Economical

The next bump up in capability is the Orion AstroView Equatorial mount ($250) to which you must add the single or dual drive ($140, recommended) motors for a total outlay of about $390. It’s carry weight is around 31 pounds including batteries but it can handle 12 pounds of payload and you may not need to use all 12 pounds of counterweight. Orion does have mounts in between, but I say skip ’em.  The disadvantage here is that it really can’t take a telescope, there is no autoguider port, and no “GoTo”. But it does come with a polar alignment scope. Tracking accuracy at sidereal rate is pretty good. I haven’t pushed the mount beyond 450 mm so I can’t make final conclusions. One advantage over a normal “tripod” is that the extra weight makes this solution much more stable than a conventional tripod. The latitudes range for use is 18-63 degrees. With some finagling I was able to physically get the angle down to 0 degrees – but you can’t track the RA axis at that angle. Two more drawbacks are that the tripod is lightweight aluminum square tubing with a plastic clamp – it’s begging to fail from overtightening, and the drive motor connectors stick out like sacrificial lambs begging to be broken off when placed down on a hard surface incorrectly.

Approach C: Serious Astrophotographer

Once you move up the value chain you will want to get a “GoTo” scope. This moves you from the $400 neighborhood to the $1400 address which gets an Orion Atlas EQ-G that can support 40 pounds of payload, and costs about 80 pounds in back buckling schlepping to move it around (22 pounds are counterweights).  The good news is a modestly sized telescope can go on this thing – you could even give your toddler a ride. The bad news is there is still plenty you’ll want to buy: an autoguider… and perhaps even a telescope. If that’s where you want to go, perhaps the best bet is the even stronger solution, the Orion Sirius EON 120mm EQ-G GoTo APO at $2800.  None of the above  include an autoguider, or the few miscellaneous parts you’ll need to attach your camera.   If you want a slightly less expensive, lighter system the Sirius mount isn’t a bad deal.

If you KNOW you’re going to put a immodestly sized scope on your mount, you might find yourself in the $4,000 district where a forklift or weightlifting team can help you move the apparatus around. Trust me, $4,000 still isn’t the penthouse suite!

Approach D: Insanely Serious Astrophotographer

Actually I can’t recommend anything in this category because it enters a realm where I’m not willing to go financially. For a down payment on a house you can get a large refractor (or reflector), massively accurate GoTo mount with autoguider, a high-end imaging camera, and a wheelbarrow full of accessories. Names like Losmandy, Takahashi, AstroPhysics and others rule this realm.

Polar Alignment

  • http://www.astronomy-pictures.com/Imaging-Tips.htm#zero
  • http://www.petesastrophotography.com/polaralignment.html
  • http://www.astronomy-pictures.com/Zeroing%20it%20in.%20Using%20a%20DSLR%20or%20CCD%20to%20Align%20Your%20Scope.pdf