Polar align without view of SCP or in daylight

[neurosis3000]

Has anyone used this method before?
https://skyandtelescope.org/observing/daylight-polar-alignment/

I can’t view SCP so I always have issues polar aligning.

Cheers,
Reggie

[mental4astro]

Reggie,

The following method also doesn't need a view of the SCP, though only for night time alignment:

http://www.iceinspace.com.au/forum/showpost.php?p=1413939&postcount=8

Alex.

[kon1966]

can help with true south during day at anytime. All you need is a vertical shadow of some sort on a flat surface.

If you have an android device, download solar polar align app. It does not use compass.

Im my photo, if my grout are the shadow, then the sides of the phone are pointing to true south as well as the large lines. The top and bottom are at right angles so you can put a piece of wood and align your telescope legs against them.

You can also permanently mark the surface as well.
Regards
Kon

[Startrek]

Reggie
Here ya go and drawing attached


Finding Celestial True South using Solar Noon ( Shadow ) method ( For Alignment of your Mounts Tripod )

Items needed
1 length of 12mm diameter timber dowel or rod with a 2mm deep hacksaw cut 90 degree criss cross on one end
2 x 3m pieces of 1mm diameter cotton builders string or similar
4 house bricks or pavers or weights
1 x straight edge , ruler or aluminium angle about 500 or 600mm long
1 x fine point permanent marker
1 x Stanley or similar 350mm builders bubble level
1 x PC or laptop with Stellarium down loaded or Smart phone

Location
Your observing location ( approx 2m2 ) or where you will set up your telescope mount should be a reasonably flat or level area with a good view of the sun around midday ( a paved, tiled or concrete ground is preferable) At a remote site you will have to clear the ground of rocks and debris to leave a fairly clear flat area

Procedure
Setting up for your solar noon shadow
Erect timber dowel or rod vertically at your telescope mount location and use the 2 strings to anchor the dowel to the ground like tent guy ropes at north , south , east and west. Use bricks , pavers or weights to hold down the strings tight so dowel sits firm upright. Now use a bubble level vertically against the dowel to ensure it is 90 degrees on all 4 sides N,S,E, W, The hacksaw cuts in the top of the dowel make it easy to make fine adjustments
either way

Finding Solar Noon Time

(Using a Planetarium like Stellarium )
Start your PC or laptop in the morning and open Stellarium
Move your planetarium view to the left or right until you reach the north (N) cardinal point and move up until you see the Sun
Click on the Sun and you will see it’s read out data on the top left of the screen
Now open the Time window and move the time forward until you view the Sun bisecting the north meridian line or until read out data on Az/ Alt degrees goes from 359 degrees to 0 degrees
At that very point and time , record the time from the clock ( eg 12.35pm )This time is your Solar noon time which you will use later

(Finding Solar noon on a website )
Most meteorological websites show solar noon times at or near your location

Marking your Celestial True South Line
Go to your location about 15 minutes before the designated solar noon time with your smart phone , ruler or straight edge and permanent fine tip marker
The timber dowel or rod should be casting a 500mm long thin shadow across the ground towards the south
At exactly solar noon time , mark a line on the ground from the centre base or the timber dowel or rod outward along the exact centre of the shadow to at least 500mm out. Use your ruler or straight edge and be as precise as you can.The more precise you are , the closer you will be to true south and eventually polar alignment.
This line represents the True South line and can now be used again and again when you set up your tripod , mount and telescope
I found the above method of finding True South far more accurate than any compass with magnetic declination or phone app etc....

Old fashion way but never ever fails
Cheers
Martin

[neurosis3000]

Thanks, all! I’ve now got a couple of things to try 👍🏼

That’s really good info

Cheers,
Reggie

[sunslayr]

If your mount is level and your glutches are set to 0, I've found you can just set up the mount pointing roughly south then use the hand control to slew to the sun. Assuming you have the altitude pretty close, just use the azimuth bolts to get it as close as possible to the sun. Then at night I refine it. Obviously make sure you don't point at the sun without protection :rofl:

[neurosis3000]

Thanks, David! I actually wasn’t planning to observe the sun. I was more looking for a way to polar aligning without the SCP and came across that link. The spot is quite restricted. On the south I can only see above about 30° above horizon and above 45-50° on the east. I pretty much only have clear viewing to the west and north plus directly overhead.

😅

[sunslayr]

Yeah that's pretty similar to me, I usually set up in the afternoon using the sun and my mount as a sort of sextant. Saves time when I want to drift align if I'm mostly there already.

[neurosis3000]

I've read that to drift align, I have to use a star around 20 deg above the East horizon but unfortunately, I have no view of the East below about 45-50 deg so not sure how well that would work.

[Merlin66]

Reggie,
You can use a star in the West instead....

[neurosis3000]

Thanks, Ken! Will try that! 👍🏼