Polar scope alignment

[Don Quixote]

I am not sure who even uses their polar scope anymore with all the AP and electronics involved.
But for those Neanderthals who still use a polar alignment scope and have ever had to fiddle with aligning the Polar scope with your mount, as I do from time to time, I have made a way to make that fiddle much easier and much faster to bring alignment to mount back in tune.

The little set screws in these polar scopes are a pain in the neck.
I removed them and installed #4 focus clamp screws with long shafts and thumb screw knobs. With this rig I am able to make this alignment to my mount in about 5 minutes.

I can drive 2 screws at once which makes the process 9 times more efficient and 18 times faster.

I know we don't have to do this very often, but if we depend on our Polar alignments we should check the scope to mount alignment from time to time.

Well that is all I have. It has been useful to me. I hope it may be useful to someone else.

See image:

[bladekeeper]

That's a great mod, Mark!

[bobharmony]

Sweet - I gave up on trying to align the polar scope a long time ago and drift align instead. If I had these screws instead of those grub screws maybe I never would have to go that route! Nice fix!

Bob

[UlteriorModem]

Very nice! I thought about doing something like that since mine actually uses recessed grub screws :p

I still use mine once in a while but since for me at least it is just a ball park adjustment I don't fuss with it's alignment. I did when I first got it so for now 'close' is close enough.

I still think that a good drift alignment is the best alignment. But at least the scope gets me in the ballpark for a starting point.

[Mac]

Sweet - I gave up on trying to align the polar scope a long time ago and drift align instead. If I had these screws instead of those grub screws maybe I never would have to go that route! Nice fix!

Bob

Bob
Do you have guide that shows what direction to move the mount for a specific drift direction?

The videos I have watched on how to do drift align is not working for me, so I am doing something wrong.

For example : Imaging Andromeda last night and it was drifting to the right and very slightly down over the 30 minutes, so I was limiting it to 40 seconds before I was loosing a round star.

What would be your adjustments in the above scenario?

Thanks
Steve

[UlteriorModem]

The drift alignment should be completed well before you start imaging! It is done separately.

I make notes in the drift alignment app That will say something like "OTA East side of pier, pointing north Clockwise raises".

But you will have to experiment first to know which way is which. It is a guessing game at first.

So if the trend line in the drift alignment app is trending downwards I know which way to adjust.

Same sort of note for the Altitude.

This is a pretty good 'how to' video.

You will have to 'rewind' it some as this links kind of starts in the middle. :veryconfused:

https://www.bing.com/videos/search?q=ph ... M%3DHDRSC3

[Mac]

The drift alignment should be completed well before you start imaging! It is done separately.

I make notes in the drift alignment app That will say something like "OTA East side of pier, pointing north Clockwise raises".

But you will have to experiment first to know which way is which. It is a guessing game at first.

So if the trend line in the drift alignment app is trending downwards I know which way to adjust.

Same sort of note for the Altitude.

This is a pretty good 'how to' video.

You will have to 'rewind' it some as this links kind of starts in the middle. :veryconfused:

https://www.bing.com/videos/search?q=ph ... M%3DHDRSC3

I did align it before imaging but obviously not very well because it was still drifting to the right and down slightly and was noticeable when previewing the images.

I am adding a guide scope next week so hopefully I won't need it but I prefer to know how to get it as close as possible before guiding.

Thanks for the video link.

[UlteriorModem]

The biggest catch or the mistake most often made is not waiting long enough to establish a 'true' trendline. Depending on where you are pointed in the sky it can take several minutes between adjustments before the true trend is represented.

The guy in the video explains all that

[bobharmony]

Bob
Do you have guide that shows what direction to move the mount for a specific drift direction?

The videos I have watched on how to do drift align is not working for me, so I am doing something wrong.

For example : Imaging Andromeda last night and it was drifting to the right and very slightly down over the 30 minutes, so I was limiting it to 40 seconds before I was loosing a round star.

What would be your adjustments in the above scenario?

Thanks
Steve

Steve - I drift align using PHD2 during initial setup for each imaging session. I always point the scope at the Celestial Equator and a few degrees west of the meridian to make the azimuth adjustments, and at the Celestial Equator about 60 degrees east of the meridian for the altitude adjustment. In those locations I have figured out which way to move the scope depending on which way the DEC line is trending, for example if the DEC line trends below level for the azimuth adjustment, I know I need to adjust the scope to the east. I have made notes in PHD2 to tell me that, so I don't have to figure it out by trial and error every time out.

Trying to drift align on a specific target each time would not give consistent results. If the object was east of the meridian on one night, and west of the meridian on another night, you would have to adjust in opposite directions for the same downward trend on the two different night. By picking a fixed spot to point to for adjustments each session, I know what adjustments I need to make every time out. It is just much easier to keep track of using this method.

Bob

[Don Quixote]

Is anyone familiar with Kochabs Clock?

[UlteriorModem]

Is anyone familiar with Kochabs Clock?

I had never heard of that so I looked it up. Interesting concept but looks time consuming.

[Mac]

Bob
Do you have guide that shows what direction to move the mount for a specific drift direction?

The videos I have watched on how to do drift align is not working for me, so I am doing something wrong.

For example : Imaging Andromeda last night and it was drifting to the right and very slightly down over the 30 minutes, so I was limiting it to 40 seconds before I was loosing a round star.

What would be your adjustments in the above scenario?

Thanks
Steve

Steve - I drift align using PHD2 during initial setup for each imaging session. <snip>

Bob

Thanks Bob... I was visually watching the drift on my DSLR live view while zoomed in to max on both LiveView and the lens using whatever star was just above the tree line in the E and S. Watching some more Youtube videos has helped me understand the direction and what to change and hopefully I won't need it with the new guide scope, due to arrive tomorrow!!!

[Don Quixote]

Is anyone familiar with Kochabs Clock?

I had never heard of that so I looked it up. Interesting concept but looks time consuming.

Yes I have read the detailed instructions and etc, etc.
But here is a very simple application for an EQ mount. It will not work well in urban LP because of the extinction of Kochab, or even Polaris for that matter, but here it is.

With the weights off and no scope mounted.


1. Level the mount as usual, oriented toward Polaris in "Home" position and tighted clutches.

2. Put Polaris in the PS FOV by DEC and AZ adjustment knobs on mount.

3. Orient PS so that "O" o'clock and "6" o'clock are oriented correctly as per a clock face.

4. Locate Kochab naked eye.


5. Loosen the RA clutch and swing the weight bar up so the Polaris and Kochad line up across the top of the weight bar.

6. Adjust AZ and DEC on mount to align Polaris with "6" o'clock in PS reticle.

You are now polar aligned with the correct hour angle.

I have been as close as 5' repeatedly with this method on my LXD mount.

I have attached 2 PS articles.
The LXD 75 reticle has a small circle indicating where to put Polaris.

In the Skywatcher PS reticle I use the "6" o'clock position.

This method is NOT my invention.
Here is a link. This method can be used with PS of different reticle. It works the same.

Weasner's LXD55 / LXD75 Tech Tips Page
http://www.weasner.com/lxd/techtips/pol ... nment.html

For best accuracy of course the PS must be aligned as close as possible with mount, hence my original post.

Obviously this will not apply to the Southern Hem. Maybe there is a way but I have no idea.

Skywatcher

LXD 75

[Gulf Coast Guy]

I am not sure who even uses their polar scope anymore with all the AP and electronics involved.
But for those Neanderthals who still use a polar alignment scope and have ever had to fiddle with aligning the Polar scope with your mount, as I do from time to time, I have made a way to make that fiddle much easier and much faster to bring alignment to mount back in tune.

The little set screws in these polar scopes are a pain in the neck.
I removed them and installed #4 focus clamp screws with long shafts and thumb screw knobs. With this rig I am able to make this alignment to my mount in about 5 minutes.

I can drive 2 screws at once which makes the process 9 times more efficient and 18 times faster.

I know we don't have to do this very often, but if we depend on our Polar alignments we should check the scope to mount alignment from time to time.

Well that is all I have. It has been useful to me. I hope it may be useful to someone else.

See image:

great minds think alike I guess. Wasn't long after I got my LXD75 that I got these.

http://www.scopestuff.com/ss_l5sf.htm

[Gulf Coast Guy]

Also the polar alignment routine included with Sharp Cap Pro works well enough for me with a 50mm f3.8 guidescopeand a ZWO ASI120mc

[John Baars]

The quick and old school way: No apps or planipshere needed.

Make sure your telescope is in home position and well aligned with your finder.
Put Polaris in your finder by moving your whole mount. NO RA or DEC axis.
The telescope is polar-aligned accurately enough for visual or manual star- hopping use.

Good enough for goto use: Planisphere (or any polaris alignment app) needed.

Polaris makes a complete circle around the true pole in 23hrs and 56 minutes.
This circle can be found in any app or even on any planisphere. The right position as well. A planisphere will give you the same orientation as your straight through finder if you hold South down. Note that a simple planisphere gives the same position as a sophisticated app.
Put Polaris in the right position in your finder. Make adjustments with your mount (NO RA or DEC axis) in order to put Polaris on the right spot in your telescopic eyepiece-view with a field of around 1,3 degrees. The mount is ready for goto.

View of Polaris in your finder and telescope ( without prisms or diagonals)

Photographic
Here you will need the drift align, kochab clock.
Or the polar scope if you do not intend to expose for minutes on end.
A sophisticated app may be of some help, but not necessary.

[pakarinen]

Is anyone familiar with Kochabs Clock?

I've read about it, but never used it.