Polarscope 1_english – Sky-Watcher EQ3GOTO MOUNT User Manual

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When your equatorial mount is polar-aligned it is able track the sky easily and hold targets in the eyepiece with

just occasional adjustments to the RA control cable. If your mount is motorized it can hold objects in the

eyepiece almost indefinitely. An accurate polar alignment also greatly reduces the number of guiding

corrections that are needed during long exposure astrophotography.
However, for all but the most critical photographic applications, your polar alignment does not need to be

perfect. Your mount will provide excellent performance even if there is some error in the polar alignment.

SkyWatcher has developed user-friendly equipment and procedures to minimize such errors, and this

makes an adequate polar alignment easy to accomplish.

APPENDIX A - PRECISE POLAR ALIGNMENT

FOR NORTHERN HEMISPHERE

Fig.s-2

Fig.s-1

Aligning the polar scope reticule
The polar scope needs to be aligned with the polar axis of your mount. The steps below tell you how to perform

this alignment. Note, you can do this procedure at night while pointing at Polaris. However, it is probably easier

to do it in the daytime using a distant point as your target (e.g, a street light a couple of hundred yards away). If

doing the procedure during the day, you might find it convenient to set your altitude to near parallel with the

ground to put the eyepiece of the polar scope into a comfortable position. Just be sure to leave room to make

vertical adjustments in both directions. Also, do this procedure without a telescope or counterweights attached. It

will make turning the mount a lot simpler.

PREPARING THE MOUNT

Locate a distant object and place it under the cross at the

centre of the polarscope reticule.
Rotate the mount in RA 180 degrees (i.e., 12 hours on the RA

setting circle).
Note the displacement of your target from the centre of the

crosshairs (Fig.s-1). If it is not displaced at all, it means your

polar scope reticule is already properly aligned and you don't

need to do any more. If it is displaced, continue with the next

step of the alignment procedure.
Use the three adjustment screws on the polar scope to move

the reticule so that exactly one-half of the displacement is

corrected for. For example, if the displacement were about

half an inch in the direction of 1 o'clock, then you would adjust

the cross at the centre of the reticule to go half the distance in

that direction (Figure s-2).
Now continue to move the cross using the altitude and

azimuth adjusters on the mount. When the target is back

under the cross, go back to step 2, but this time rotate the

mount 180 degrees in the opposite direction. If you still get

displacement of the target, repeat steps 3-5.

One bolt should always be loose when doing adjustments.

Gently tighten both bolts when your adjustment is complete.

If target drifted to here

adjust reticule to

place it here (half

the distance)

Setting your latitude

Remove the caps from the upper and lower ends of the RA axis so you can look into the polar scope. Adjust the

north and south T-bolts on the mount so the latitude indicator points to your local latitude (Fig.2). Look through

the polar scope and adjust the azimuth and altitude controls as needed so that Polaris appears in the view of the

polar scope. Once you see it you can use one of the simplified procedures below to place Polaris at the correct

position for an accurate polar alignment.