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New to GOTO question

Joe
 

First thing, I have never used a GOTO mount before so please be kind with my questions.
I finally have some clear weather here in the NE USA and I took my working Onstep Vixen GP converted mount outside to try it for the first time, but It is very windy and cold here so I wasn't outside long!
My basic understanding of how the these mounts is a bit lacking. Let me see if I have this correct and what I am doing wrong... My description is based on my position of looking through the polar sight finder.
The RA controls the East/West movement of the mount, when you press WEST the mount should move counter clock wise to the west. this is the same no matter where the DEC is. basically when the mount is tracking (counter clock wise) it is moving to the west.
When moving the mount North and South is where I am confused, Lets say my RA is to the West, when I move north on the DEC my mount should be getting lower, when I move South it should go higher? What happens when my RA is East? do they reverse?
I am not sure if I need to swap my motor direction on either axis.

I am connecting to Sky Safari on my phone, and I am having some problems getting the 3 star alignment. While watching the screen the mount isn't agreeing to what I am seeing on the device.




Khalid Baheyeldin
 

On Sun, Nov 24, 2019 at 09:24 PM, Joe wrote:
The RA controls the East/West movement of the mount, when you press WEST the mount should move counter clock wise to the west. this is the same no matter where the DEC is. basically when the mount is tracking (counter clock wise) it is moving to the west.
When moving the mount North and South is where I am confused, Lets say my RA is to the West, when I move north on the DEC my mount should be getting lower, when I move South it should go higher? What happens when my RA is East? do they reverse?
First, you should read the FAQ, about the behaviour of N and S when the scope has just powered up (and assumes it is pointing to your North Celestial Pole).

https://onstep.groups.io/g/main/wiki/Frequently-Asked-Questions-%28FAQ%29

I am not sure if I need to swap my motor direction on either axis
Test it indoors first, without an optical tube.

Enter the location, date and time, and UTC offset, from the Android App.

Using a planetarium, locate a star due east or due west.

Start a 1 star align. Select star that is either west or east, midway to the zenith.
Wait until the slew is complete, then check if the mount is pointing correctly to where it should be.

If not, then configure with reverse on the axis you are suspecting and repeat the test to see if you end up where the star should be.

Joe
 

Thanks Khalid, inside everything works as expected while using the laptop. Outside I was testing with my phone and SkySafari. The motors don’t need to be reversed.
When on the configuration page with my phone, first of all on Safari the page is minimized so the buttons are very small. When I can press a button, get a text input box selection rather than it just pressing the button. See the photo. This I think is a large part of the problem. Safari and Explorer handle HTML very differently.
Also when you power on OnStep it’s expecting new alignments or it is it remembering the old ones? I’d think it wants new data. You simply start a new 3 or 5 star alignment from power-up?


simingx@...
 

It seems like you're trying to access the Onstep webpage from within Skysafari, try using Safari directly instead?
I actually use a spare Android phone for use with Onstep... ;)

tomofreno2000
 

Hi Joe,

Your scope must be moved to point at Polaris either manually or using the controls under Guide/Focus (you can select different speeds under Options at the upper right on your phone or tablet - 3 dots on mine).  Before you go to Guide/Focus, select Options/Tracking to turn on tracking.  There are a few things you must do each time you start OnStep as Khalid mentioned:
1) On the main screen you must go to Observation Sites under Options and ensure your location and UTC Offset are correct.  Correct them if not and select Upload.
2) You must set the date and time. That is done on the Initialize/Park page.
3) You must ensure that OnStep and SkySafari agree on time/date, and that it is correct.
4) Once the scope is pointed at Polaris you must select Home/Reset under Initialize/Park to reset OnStep ensuring it knows the scope is pointed at Polaris. Then you can start an alignment.

Once alignment is complete you can turn off OnStep and connect to the scope with SkySafari and use it from then on.  I usually Goto a brighter star near the object of interest first, center it, select Align is SkySafari, and then Goto the object of interest for better accuracy. If your alignment is very accurate you may not have to bother with that.

Khalid Baheyeldin
 

On Mon, Nov 25, 2019 at 05:25 AM, Joe wrote:
When on the configuration page with my phone, first of all on Safari the page is minimized so the buttons are very small. When I can press a button, get a text input box selection rather than it just pressing the button. See the photo. This I think is a large part of the problem. Safari and Explorer handle HTML very differently.
As simingx said: you are using a browser, not Sky Safari itself. Therefore the buttons are very small.
If your phone is Android, then just do the initial startup (date/time, location, align) from the Android App, since it is full featured.

Also when you power on OnStep it’s expecting new alignments or it is it remembering the old ones? I’d think it wants new data. You simply start a new 3 or 5 star alignment from power-up?

When you power on OnStep, it does nothing. It assumes it is pointed at the celestial pole of your hemisphere (not Polaris, it is ~ 40 arc minutes away), but does not power the motors or track or anything. It assumes that you will do an alignment (1 or more stars). Once you start an align, the motors kick in and tracking starts.

You can also start tracking manually. In this case, OnStep assumes that you are perfectly polar aligned.

The exception is when you enable auto tracking at startup (see previous message for details). It then becomes like starting tracking manually (assumes perfect polar alignment).

Another exception is if you have a permanent installation, i.e. an observatory, then things are different: you can align once, and then use park at the end of session, then unpark the next session, and the alignment data is saved. It does not make any sense to retain align data unless the mount is fixed.

Once you are aligned (or unparked) you can then switch to Sky Safari for slewing to objects and so on. Hence the recommendation to use the Android OnStep app initially, just like tomofreno said.

Joe
 

I don’t own any android devices, just a windows 10 laptop an IPhone and a MacBook. So I can’t access the OnStep App.
What I can access is SkySafari and within that the settings of the OnStep page at 192.168.0.1. 
Under the “control” page I see options for 1,2 and 3 star align. When I press any of these buttons, I get a pulse from the motors on the mount. I don’t see any options to choose from stars to align. 
So do I roughly align the tube on Polaris and click “1 star align” and then align other stars from within SkySafari? Perhaps I’m just missing something else? The buttons on this page are difficult to use on the iPhone: the size, the input selection mode and it also minimizes the page sometimes. Tonight I’ll take the laptop outside and try that.
I’m also looking at the Stellarium Mobile Plus app. The documentation says you need to flash with onesp 1.86, which is included with OnStep V3.0. The version I’m on is Onesp 1.7 and OnStep 2.22. 
This was downloaded from the link in the online configuration generator. I gather I’d need to try a different branch for it to work?

It is pretty clear out, so I’ll give this another shot tonight. It’s also not freezing like last night, so I’ll spend more time with it.

Khalid Baheyeldin
 

On Mon, Nov 25, 2019 at 08:49 PM, Joe wrote:
What I can access is SkySafari and within that the settings of the OnStep page at 192.168.0.1. 
You can start an n-Star align from that web page.

Under the “control” page I see options for 1,2 and 3 star align. When I press any of these buttons, I get a pulse from the motors on the mount.
I don’t see any options to choose from stars to align. 
Great. That is all you need, then you need the subsequent steps.

So do I roughly align the tube on Polaris
You should roughly align Polaris before you power up, since that is the position that OnStep defaults to.

and click “1 star align”
No.

Start a browser with the 192.168.0.1 address.
Go to the Control tab
Then just press the 3 star button, and that will be the final interaction you have with that web page.
The RA motor will star buzzing (i.e. OnStep is tracking).
You should now close the browser since you started the align.
From that point on, everything can be done in Sky Safari.

From Sky Safari, you need to select 3 bright stars, far apart, say two on one side of the meridian, and one on the other side.

For each star you do the following:

- Slew to the star, and wait until OnStep beeps.
- Using Sky Safari, center the star in the eyepiece the best you can.
- Sync on the star.

Repeat for the other 2 stars (slew, center, sync), and you are done.

OnStep is now aligned, and will compensate for the alignment errors when slewing.

I’m also looking at the Stellarium Mobile Plus app. The documentation says you need to flash with onesp 1.86, which is included with OnStep V3.0. The version I’m on is Onesp 1.7 and OnStep 2.22. 
This was downloaded from the link in the online configuration generator. I gather I’d need to try a different branch for it to work?
What I recommend is that you ignore any additional clients for now.
Get the web page + Sky Safari working, then worry about other factors later, which will require new versions ...etc and will only add to the confusion.

Khalid Baheyeldin
 

Moving the reply from Joe back to the topic where it belongs. Easier for future users to follow that way.

Also thanks Khalid!, on day #2 your advice about only using the web page to select 3 star alignment only went well.
Great to hear.

I used to do some web design, perhaps a style sheet can be added to format the size of that page for different devices?  
I do web development for a living, but mostly backend. I intentionally stay away from front end stuff (CSS and JS in particular).

In this file, you will find the HTML for the web server is. I don't see styling tags (div), but they can be added. If you can convert it to a truly responsive design (adjusts to screen width automatically, e.g. desktop, tablet, phone; increase font size and/or button size, ...), that would be a great improvement.

I was able to skew to stars from both east and west with a 24mm EP. I think I have a little slop in the mount that can be tuned out and the brackets John made will help the slack I have in the drive system, no way to adjust tension with the way it is now.
If there is slop because of how the mechanical parts are put together, that is different from backlash.
Backlash is from gears meshing together. If you have a gear box, there will be some backlash, and you can compensate it in OnStep using trial and error on a land object.
If you only have pulleys and no gear box, backlash should be minimal.

The upper DEC on The GP bracket that John redesigned has a slot that fits square into the mount and can be adjusted. I’m not sure about how much tension is needed on the belts.
They should be tight but not under too much stress.

Some more of my issues may be caused from belt drives that aren’t really that square..
Yeah, you have to visually align them so they are not skewed on one pulley from the other.

Any tips for performance would be appreciated! This whole process has been a challenge and rewarding.  I’m enjoying it!
The basic advice is to diagnose the source of any issue before trying to fix it.
Too many fixes to non-existent problems is bad and will only confuse and frustrate you.

Post here what the symptom is, and others will pitch in with their experience. Then you can try the fixes, and report back.