Date   

Re: Exos 2GT - PMC-8 Thread

hubbell_jerry@...
 

Hi Ben,

I was looking at your setup diagram and noticed the USB to DB9 serial adapter. The cable you have linked has a Prolific chipset. I have found that the FTDI chipset is more reliable and is the recommended chipset for use with the PMC-Eight. Chris and others may be able to speak more to the use of Prolific or other chipset USB adapters. The Prolific chipset may work fine and I am recommending the FTDI FT232 chipset because I know they work, that's all.


Re: Exos 2GT - PMC-8 Thread

W. Christopher Moses
 

It is 12V, I think 3A. Everything else runs off a 10A supply, but I'll probably move the PMC-8 over to the 10A supply just to eliminate the cable.

You can get a good idea of my wiring here:


I just posted some pictures of the above the mount set-up


Re: Exos 2GT - PMC-8 Thread

W. Christopher Moses
 

I've used both with the PMC-8 without problem, but I don't trust the Prolific.  I've seen to many problems with them on other astro setups, including my own.


ExploreStars and A Wireless Connection Notes

W. Christopher Moses
 

Hi Everyone,

I'm headed out to a dark site this weekend for a few days, which means I will have a few days of downtime.  I was thinking of writing up some quick notes about  ExploreStars and using a wireless connection.  Basically, which use cases benefits from each and which don't, as well as other things I've learned.


If this would be a help to anyone, I'll do it.  Otherwise...


Let me know if there is any interest.


Thanks,

Chris


101 level questions

Devin Gingrich
 

Greetings!

I am strongly considering getting an exos2-GT with PMC-Eight, as opposed to a Celestron AVX, to go along with my newly acquired first gen Comet Hunter (so dang excited!!). That said, I have a few basic questions (my current mount is a Celestron):

1) Can I calibrate the scope using a third party program (SkySafari 5 Pro) or do I need to calibrate it using ExploreStars First, then hand off control to SkySafari?
2) What is the timeline for a native macOS or iOS variant of ExploreStars?
3) What is the process for doing daytime (solar observation) alignment?
4) Has there been any involvement with the PixInsight community? Their INDIClient would seem to me to be an extremely interesting point of integration (here’s an older link): https://pixinsight.com/forum/index.php?topic=9852.0


Re: ExploreStars and A Wireless Connection Notes

Ben K
 

I would happily read your notes, but don't feel obliged, of course.


Re: Exos 2GT - PMC-8 Thread

Ben K
 

Much obliged to you both for catching that.

I've replaced it with an FTDI chipset cord.


Re: Exos 2GT - PMC-8 Thread

Ben K
 

Jerry / Chris,

Do you know if the PMC expects positive tip/negative sleeve or negative tip/positive sleeve.

Or, can you upload a photo of the label on the adapter?

Currently looking at this, provided the polarity is right:



Re: Exos 2GT - PMC-8 Thread

W. Christopher Moses
 

Hi,
I assume the tip is negative and the sleeve is positive. That is the convention, if I recall properly. Actually I spend a good amount of time today splicing wires, but at 5am my brain is getting foggy. I'll double check tomorrow if you want but I doubt they are doing anything unconventional. Of course, I've said similar things before...


Re: 101 level questions

W. Christopher Moses
 

Hi,
I'm glad you are looking at the pmc-8 system.  So far, I really like it.  I have the G-11 version.  You might want to check out my main thread for it:


It's really more about the pmc-8 than the G-11. I should start a new thread with a better name.

Your questions:
1. I assume you mean the star alignment.  You can do that from ExploreStars or from any ASCOM compatible programs. I think SkySafari is strictly iOS and Android, so you could not use it.

2. Have to ask Jerry 
3. Have to ask Jerry.
4. I can't speak for Jerry or Explore Scientific, but INDI is something I find very interesting.  It seems to have a more mature architecture than ASCOM. Unfortunately, it is not easy to port to windows. I belive such a project is under way and even operational to some degree.  How much of that can be used by PI is another question.

I'll take a look at the Windows port.  If it is mature enough to justify some work, I'll look into writing an INDI driver for the pmc-8


Re: Exos 2GT - PMC-8 Thread

hubbell_jerry@...
 

Hi Chris,

You are NOT correct about the power connector. The outside barrel is NEGATIVE and the Tip is POSITIVE. There is reverse polarity protection on the board so if you were to wire it backwards nothing would light up.


Re: 101 level questions

hubbell_jerry@...
 

The ASCOM driver does not currently have a 2 or 3 star sky alignment incorporated, it just has a SYNC or as it is sometimes referred, a 1 star alignment. The SYNC does nothing to correct for polar alignment errors, that is the job of a 2 or 3 star alignment. You need to do a very good polar alignment and then you can correct the minor pointing errors with the SYNC command. The ASCOM Standard assumes the mount is physically polar aligned and therefore does not have any alignment functions.

The ExploreStars app is a stand alone application that is not used in conjunction with any other program. It is only meant to be a hand controller mainly for visual use. If you use a third-party program with the ASCOM driver then you will need to do a physical polar alignment so that the view does not drift while tracking.

There is no announced release date for a iOS or Android version of the ExploreStars app. I can say, though that the Android app is under active development and could be announced by the end of the year.

To do a daytime alignment is a process of aligning the azimuth axis to true north, and setting the altitude to the correct latitude value. I have used a quality magnetic compass to set the azimuth, make sure you correct for magnetic declination. Here in Virginia, the magnetic declination is +10 degrees. You can look up you location's magnetic declination on the web. Make sure you level the mount on the tripod first. In the following, you will be moving your mount with the ExploreStars application. You want to start out by positioning your mount using the index marks so that you are weights down (NORTH) and Declination 90 degrees (straight up and down when observing your telescope from the SOUTH, looking NORTH).

After you have aligned your mount on the azimuth axis to true north, then you can set the altitude by moving your mount (via the coordinate input screen) to RA close to the LMST (local mean sidereal time). I would suggest you move it just west of the Meridian say to 5 minutes before the current LMST, and then move your mount in DEC to make the scope point UP and to a value equal to your LATITUDE. So you would enter a value for DEC of 38 degrees, if your LATITUDE is 38 degrees.

What this does is point your mount vertically the ZENITH. Of course your telescope will be close to ZENITH but this is when you move the ALTITUDE axis on you mount to point the telescope straight up. You can measure this by laying a level across the top of your telescope tube (making sure it doesn't touch your objective if it is a refractor) and leveling it. This is when you can be sure it is pointing close to zenith.

This is how you can get a pretty good polar alignment during the daytime.

We have not done any work with PixInsight, but I have looked at the INDI stuff. I have talked with several people interested in developing an INDI driver, and our current position is that we will leave that up to others to do. We will supply all the needed information about our controller of course to facilitate that.


PMC-8 Machine On Internet

W. Christopher Moses
 

I was going to spend some time this weekend trying to get the PMC-8 connected to my home network.  But, It looks like I'll be out at a dark sky site for a few days.  I did, however, have an idea for a workaround.


The idea is to put an additional network adapter on the machine.  I cheap USB ethernet adapter should work.  Then, install a Virtual Machine on your system.  Install all your astro stuff on the VM and connect the VM to USB ethernet, which is connected to the PMC-8.


Then, just RDP into the host machine and maximize the VM. Voilla.


As a bonus, you don't have to play around with terminal programs and configuring the PMC-8 settings.


Sounds like it should work, but I can't say I've tried it.


If anybody has experience with VM networking, please chime in.


Just a thought.


Chris


Re: Exos 2GT - PMC-8 Thread

W. Christopher Moses
 

Yeah, I knew I shouldn't have answered that at 4 am.


Re: PMC-8 Machine On Internet

Michael Fulbright
 

I'm not sure you need a VM.  If windows sets up the routes properly then any traffic to the PMC8 subnet (192.168.47.0/24) will go there and your USB ethernet adapter should get a route for the subnet your remote machine (which connects via RDP) lives on as well as a default route to handle any traffic outside those two subnets (the internet).

So you should just be able to add the USB ethernet and everything will work.

I don't really do much on Windows but I image there is a way to query the current routes on your machine.

Michael Fulbright


On 7/19/2017 10:27 AM, chris_moses@... [ESPMC-Eight] wrote:
 

I was going to spend some time this weekend trying to get the PMC-8 connected to my home network.  But, It looks like I'll be out at a dark sky site for a few days.  I did, however, have an idea for a workaround.


The idea is to put an additional network adapter on the machine.  I cheap USB ethernet adapter should work.  Then, install a Virtual Machine on your system.  Install all your astro stuff on the VM and connect the VM to USB ethernet, which is connected to the PMC-8.


Then, just RDP into the host machine and maximize the VM. Voilla.


As a bonus, you don't have to play around with terminal programs and configuring the PMC-8 settings.


Sounds like it should work, but I can't say I've tried it.


If anybody has experience with VM networking, please chime in.


Just a thought.


Chris



Re: PMC-8 Machine On Internet

W. Christopher Moses
 

Excellent! I like it!
I will look into it.


Re: 101 level questions

Ben K
 

My exos 2gt with PMC-8 just arrived this afternoon.

Haven't tested it outside yet, assembled it inside, fitted my OTA to a vixen cradle, and tested the fit in the mount.

Tomorrow I'll be booting up the PMC-8, and testing the app and confirming firmware versions and such.

Worth noting, not only is the exos 2gt with PMC-8 an upgrade because of the PMC-8, they include *2* 9.9kg counterweights and they tossed in an AC adapter for the PMC-8, it's no longer battery driven.

I'm pretty impressed so far, but I do want to figure out how to do a 2 or 3 star alignment.


Re: PMC-8 Machine On Internet

Ben K
 

Chris,

Are you thinking of adding a second network adapter to your NUC, or something else?

I'm not following, I guess.


Re: Exos 2GT - PMC-8 Thread

Ben K
 

Turns out the pmc-8 just ships with an AC adapter and that's that.


Re: PMC-8 Machine On Internet

W. Christopher Moses
 

Hi,
Yes, the idea is to use two network adapters. One conected to the pmc-8 and one connected to the "normal" network. And to then "bridge" them somehow.

There are two small advantages I see to doing this vs having the PMC-8 directly join the other network. 1) No need to play with a terminal program and the PMC-8's internal variables, and 2) No need to do number 1 each time you are moving to a new network - which may be important for people, like me, who travel to dark sky sites.

I proposed installing all the astro stuff in a VM, which is easy to do, and having the VM connected to the PMC-8, while the host machine stays connected to the internet.

Michael proposed a conceptually easier method, albeit one I have never personally tried.