POLAR ALIGNMENT
Different methods exists to do that but I use what I call the "CamelHat Trick" from the name of the Astronomy Forums user who shared his trick with me. His original post can be seen here.
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His method requires no computer but works with the camera lcd screen. It has to be done on shooting location and requires visibility of Polaris. If trees or buildings block your view of Polaris and the NCP you will not be able to use the method. You will also have to mount the aQ-Track on a tripod head that allows you to adjust azimut and altitude angles independantly.
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1- Place the camera as parallel as you can to the aQ-Track polar axis, and adjust your tripod so that the polar axis aims roughly at Polaris.
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2- Take a 30 second exposure at a high iso setting (6400). During the exposure, slowly rotate the camera by moving manually the drive arm of the aQ-Track about 180°. You should get an image that
looks like picture 1, i.e., a series of concentric circles drawn by the stars as you rotated the camera. The center of those concentric circles is where the polar axis is aiming at. Mark this spot with a piece of tape (picture 2).
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3- Take another 30 s exposure, letting the motor drive the camera to get pinpoint star like we see in picture 3. The tape position will reveal where is the polar axis of the mount pointing to, relative to the stars.
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4- By looking at the map of the Polaris area (see below), find out where is the polar axis aiming relative to the North Celestial Pole (NCP) (picture 4).
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5- Make the necessary corrections in the azimut and altitude axis of the tripod head and redo steps 3, 4 and 5 until the position of the tape aligns with NCP (picture 5).
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To make things easier you may attach a small finder (like a 6X30) to your camera so that when you move the tripod head you can see through the finder some reference stars.
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Picture 1. LCD display of the camera after rotating the drive arm 180° for 30 seconds
Picture 2. Placing a piece of tape to locate the center of rotation
Picture 3. LCD display of the camera after taking a tracked 30 s exposure.
Map of the North Celestial Pole area (NCP) created using Stellarium software. Magnitude shown to 13 approximately. Note that the NCP moves about 25" per year along the Oh right ascension line. The map show NCP position as of January 2019.
The "Coal Scuttle" asterism is made of four stars that have magnitudes ranging from 8.3 to 10.6 and are therefore very easy to find even with wide angle lenses.
Coal scuttle
Picture 4. Locating the North Celestial Pole (NCP) among the stars using the map shown below. Turns out the polar axis is aiming about 1° to the East of NCP and about 5' too low.
Picture 5. After turning the equatorial mount 1° left and slightly up another 30 s tracked exposure is taken to confirm that the center of rotation and the NCP are aligned.
Picture 6. Zooming in on picture 5 to show the coal scuttle asterism.
Precise polar alignment is critical to get good results with the aQ-Track. Polar alignment simply consists in making the aQ-Track polar axis parallel to the Earth's rotation axis as shown in the following figure. We do this by aiming the axis directly at the North celestial pole (NCP). The polar axis shouldn't deviate more than 30 arc minutes for wide angle shots (< 50 mm), 10 arc minutes for medium telephoto lenses (85 - 135 mm), and 5 arc minutes for longer lenses (300-400 mm).