Polar align “ahead” of time

Once polar aligned, if you don't move anything, you'll stay aligned indefinitely. The PS app will show a different place for Polaris, but that's just because of the different time.

Sometimes, if I know a good night is ahead and I want to maximize my imaging time, I find a clear hour or so some night before and align my scope and get all my gear ready to go, and then just un-cable and cover it until the good night. I've tested my alignment by doing it again, and even with the jiggling around of re-cabling, messing with the dew shield, and all that, I am usually spot on so long as I don't kick my tripod or something like that.

Christian Bennich:
Yeah, I normally keep it out for multiple nights as well. But I usually always trim the scope every night 🤣

I will align sometime tonight between the clouds and hope for the best tomorrow.

That is completely unnecessary , once the mount is aligned, if it does not move it remains aligned.  My equipment is permanently mounted in my backyard and I really don't remember when the polar alignment was performed.

However, it depends entirely on the strength and robustness of the mount. I remember when I had an AVX that just putting on and taking off the protective cover could cause misalignment.

As a beginner astrophotographer I could be saying a huge stupidity here but I have a hard time accepting the idea that a rig could remain aligned for long periods of time.   Wouldn’t the expansion and contraction of metals and plastics with temperature changes over 24 hours be enough to possibly mess up the alignment ?

What tool does everyone use to measure their polar alignment? I've been through (sharpcap, ipolar, polemaster, and now just using nina 3PPA) but they all seem somewhat fallible and what could give me ideal polar alignment in one app/process seems to contradict what another says is accurate. I feel like there should likely be some scientific measurement possible that then compare the methods?

I'd love it, but there doesn't seem to be any completely unbiased way to measure the accuracy of polar alignment that I know of. To really measure some of the tools\methods in a qualititave analysis would be awesome if anyone is up to that sort of task

Nick Grundy:
What tool does everyone use to measure their polar alignment? I've been through (sharpcap, ipolar, polemaster, and now just using nina 3PPA) but they all seem somewhat fallible and what could give me ideal polar alignment in one app/process seems to contradict what another says is accurate. I feel like there should likely be some scientific measurement possible that then compare the methods?

I'd love it, but there doesn't seem to be any completely unbiased way to measure the accuracy of polar alignment that I know of. To really measure some of the tools\methods in a qualititave analysis would be awesome if anyone is up to that sort of task

Preface: there are very many issues that may affect your tracking performance that wasting time on splitting hair with PA adjustments every single night is not going to affect how things really go. My mounts are permanently mounted in my back-garden and I may check at every change of season and that's it.

However, if your mount can be exactly be positioned that the OTA is pointing to the pole (say by plate solving), take a series of shots few seconds long and covering 10 minutes of time at least. Stack them up and you'll see how good is your PA (is the Pole close to the center of the image?) if you got no cone error. 

If you have a cone error then point you scope just half an hour ahead of the meridian and up to 10 degrees from the equator and keep shooting short integrations until it crosses over the meridian. The Dec drift of any chosen star will give you how accurate your PA azimuth angle is. Repeat at quadrature, either East or West (and at least 30 degrees up in altitude) and measure again the Dec drift. This will give how good your PA altitude angle is.

andrea tasselli:

Nick Grundy:
What tool does everyone use to measure their polar alignment? I've been through (sharpcap, ipolar, polemaster, and now just using nina 3PPA) but they all seem somewhat fallible and what could give me ideal polar alignment in one app/process seems to contradict what another says is accurate. I feel like there should likely be some scientific measurement possible that then compare the methods?

I'd love it, but there doesn't seem to be any completely unbiased way to measure the accuracy of polar alignment that I know of. To really measure some of the tools\methods in a qualititave analysis would be awesome if anyone is up to that sort of task

Preface: there are very many issues that may affect your tracking performance that wasting time on splitting hair with PA adjustments every single night is not going to affect how things really go. My mounts are permanently mounted in my back-garden and I may check at every change of season and that's it.

However, if your mount can be exactly be positioned that the OTA is pointing to the pole (say by plate solving), take a series of shots few seconds long and covering 10 minutes of time at least. Stack them up and you'll see how good is your PA (is the Pole close to the center of the image?) if you got no cone error. 

If you have a cone error then point you scope just half an hour ahead of the meridian and up to 10 degrees from the equator and keep shooting short integrations until it crosses over the meridian. The Dec drift of any chosen star will give you how accurate your PA azimuth angle is. Repeat at quadrature, either East or West (and at least 30 degrees up in altitude) and measure again the Dec drift. This will give how good your PA altitude angle is.

I use PS Align Pro for polar alignment. I would normally always perform a PA before an imaging session. 
I rarely spend more than 5 minutes to do my alignment. 
I have nothing blocking my view and the App makes it, at least for me, super easy to get the PA done.

Nick Grundy:
What tool does everyone use to measure their polar alignment? I've been through (sharpcap, ipolar, polemaster, and now just using nina 3PPA) but they all seem somewhat fallible and what could give me ideal polar alignment in one app/process seems to contradict what another says is accurate. I feel like there should likely be some scientific measurement possible that then compare the methods?

I'd love it, but there doesn't seem to be any completely unbiased way to measure the accuracy of polar alignment that I know of. To really measure some of the tools\methods in a qualititave analysis would be awesome if anyone is up to that sort of task

You could use the old fashioned Drift Alignment https://explorescientificusa.com/pages/polar-alignment-using-the-drift-method
No software needed--just you and your equipment
I have used it in the distant past. Takes time but works a treat.
Nowadays I use Pempro--probably once every year or two on my permanent mount