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Logieberra
05-03-2016, 02:21 PM
Hi guys,

A mate just purchased an EQ8 and has asked me to set it up. I've used a range of EQ mounts, including an earlier EQ6, but this 8 seems like a different beast.

For current/former owners, would you please confirm a few things for me, and provide web links where relevant.

1. Encoders on axis. What are they for? If you bump the mount, it never loses its place? Or for absolute unparking/parking each night?

2. Where is the default home/startup position?

3. Latest version of HC firmware? Any known issues?

4. Latest version of mount firmware? Any known issues?

5. What is the pointing accuracy like on these?

6. Does the point mapping function in EQ Mod work? Any tips?

7. Apart from AstroBurritoTortillaTequila plate solving, any other 'free stuff' out that that is simple to setup and just works? (Even ones that require online Astrometry.net)

8. PEC. How does Pempro V2 go with these mounts? Any tips?

9. Gear mesh adjustment and re-greasing. Any good sites with pics/vids out there?

Cheers

AndrewJ
05-03-2016, 02:41 PM
Gday Logan

The encoders are "relative" but it sounds like they may also have a track on them such that you can determine which side of the encoder you are on
ie like an encoder with only 2 halves.
The latter appears to be used for finding home.
As to the encoder itself, when ON, it constantly resets the motor microstep count if it gets out of synch with the encoder count.
This is non linear and means your pointing accuracy is only going to be within say 4 arcmins. So if you do bump, or manually declutch and move, it will keep track of where it is. It "may" have some nasty little gotchas if used with EQMod and no handbox. I cant test as i dont have an AZEQ6 or EQ8, but my AZEQ5 always defaults to encoders ON when booting without a Hbx and as such, i get the occasional "jump" in position for no reason.


For writing the PPEC table not sure.
The PPEC is controlled totally in the motorcards, and the earlier EQ8s were reporting a wrong microstep per worm rev count, and hence the PPEC may not record properly. You may need to suck that one and see.

Andrew

Ref http://www.dangl.at/ausruest/eq8/eq8_e.htm
for a writeup by an early purchaser

Shiraz
05-03-2016, 10:41 PM
responses above in italics

The biggest issue is backlash - the mechanism is so rigid that there is no bendiness to allow for bearing runout, slight overtightening or temperature changes of the gear mesh. The only way to get reliable operation is to allow a moderate amount of worm gear clearance in both axes and this can best be managed with weight offsets to keep the gears loaded so that they mesh only on one side. If you do that, with guiding, these mounts can give you tight round stars, hour after hour.

brian nordstrom
06-03-2016, 12:23 AM
:thumbsup: Awsome Ray , many thanks .
Brian.

Logieberra
06-03-2016, 06:35 AM
That's for sure! Thanks Andrew and Ray! I've got enough to get me started. I'll chime back in soon.

Logieberra
06-03-2016, 06:26 PM
Ray. I found some info regarding 'EQ8 Tools' --- as a way (perhaps the only way?) --- to turn the encoders off and on. I can't see the software on the Skywatcher downloads page. If you have the latest, might I grab it over DropBox? Or perhaps the Yahoo group has the latest under 'files'? Grateful for your advice, either way. Cheers.

AndrewJ
06-03-2016, 08:06 PM
Gday Logan


Do you mean turn the encoders ON/Off, or run the Auto home routine????
Turning the encoders on/off is trivial, but the current EQMod can't do it, as the EQContrl.dll that handles all the low level calls ( as well as the comms ) currently doesnt know about the new commands, and has no way to send blind commands to the mount.
I have an app that can turn the encoders on/off, start and stop PPEC and toggle the snap ports, but it currently requires sole access to the serial port.

Andrew

Logieberra
06-03-2016, 08:13 PM
I need the latest version of these tools (after 11 Dec 2014), referred to here:

http://www.iceinspace.com.au/forum/showthread.php?t=130087

And here: https://groups.yahoo.com/neo/groups/SkywatcherEQ8/conversations/messages/1114

Logieberra
06-03-2016, 08:16 PM
Yeah. That's all I'm trying to do. It's all part of my troubleshooting. Cheers.

AndrewJ
06-03-2016, 09:12 PM
Gday Logan

To turn off the encoders, just send
:W1050000" + Chr(13) and
:W2050000" + Chr(13)
With my AZEQ5, setting either the Az or Alt encoder off turns both off
but not sure how the EQ8 works.

Andrew

Peter.M
06-03-2016, 09:18 PM
I have the local astronomy.net server running on my lappy with SGP. It never fails a blind solve. It can take a while. But I'm willing to wait if Elbrus fails.

Logieberra
07-03-2016, 01:45 PM
Peter,
SGP plate solving using Elbrus looks pretty darn good!
Especially at $99.00 USD.
http://youtu.be/T32Gp-sVOnM

Shiraz
07-03-2016, 02:51 PM
don't know about versions, but the exe linked to here works OK (at least, I assume that it does what it says it does) (https://stargazerslounge.com/topic/2...thout-handset/) You don't get this level of support from the SW website - I got the impression that the tool was put together by a SW engineer as an aside to his normal work, not as a formal response from SW to a user problem (might be wrong though).

have just installed local Astrometry.net as a backup for when Elbrus drops in a hole - as Peter says, it works well.

AndrewJ
07-03-2016, 04:01 PM
Gday Ray
That exe by Frank Liu is reported to have problems if you start on the wrong side of home in some situations.
Test reports were supplied on this by a user on the EQMod forum last year. Ref thread
https://groups.yahoo.com/neo/groups/EQMOD/conversations/messages/41051


Andrew

Shiraz
07-03-2016, 05:37 PM
thanks for the heads up Andrew. I have not had a problem, but do not use it all that often.

Is there any update available?

AndrewJ
07-03-2016, 05:49 PM
Gday Ray

No idea if there is any update via Skywatcher.
I know Niall was looking at writing his own app to do the home,
but then he dropped off the grid. I was going to add its functionality to my little test app, but i dont have access to an EQ8, and BINTEL closed before i could use one of their display models to test with.

Andrew

Logieberra
07-03-2016, 09:49 PM
Yup. That's why I asked for a current version. Nothing like a 'pier strike' on a mount you're borrowing... :)

AndrewJ
07-03-2016, 10:35 PM
This is why the world needs more lab rats:D

Andrew

Shiraz
08-03-2016, 12:41 AM
Maybe let's tidy this up - in keeping with a "new starter's" thread. Please correct anything wrong with this.

.
1. you can autohome the mount and toggle the encoders on/off (if you wish) using the handset.

2. you can autohome the mount and toggle the encoders under PC control using EQ8tools, but the reliability of this method of autohome is suspect.

3.you do not need to use either autohome or encoder toggle to get the mount to work effectively under handset or PC control, but it may point (and possibly track?) slightly better with encoders off. On a fixed pier, parking will restore the mount to the home position (or other park) and autohome will rarely be needed.

4. autohome is essential for remote use if the power goes off, so the EQ8 as it stands may not reliably do remote.

I have not noticed any significant transient errors while guiding under EQASCOM, so assume that the encoder/ringcounter conflict does not upset this form of control - but I have not yet tried guiding with encoders off. Has anyone found anything different?
Also, I cannot imagine that SW would have re-invented the autohome algorithm for the PC version, so it may be that the handset also has a reliability problem - I recall once having to switch off my mount when it did something odd while trying to autohome under handset control. Only happened once, so I put it down to my inexperience.

AndrewJ
08-03-2016, 06:50 AM
Gday Ray

1. and 2. agree

Agreed

Pointing will definitely better, esp if using EQMod.
As noted, i have seen automatic jumps ( up to 4 arcmins ) in the reported microstep counts during tracking, but I dont know yet if this is real or just an internal reset.
Either way, EQMod will use this tweaked stepcount on its next goto, so it will affect goto accuracy as it happens.
With encoders off, i dont see the step adjusts, but the underlying encoder is still counting. If at a later time, you just turn the encoders ON, they WILL reset the stepcount. Just a little gotcha to keep in mind.


Not "essential" but nice.
In theory, if you have a webcam view of your scope, you could remotely fire it up and slew it to the "rough" home position manually/visually.

You would think so, but of the users on the group, one portsniffed the hbx doing the command, and the other portsniffed the PC version and they are different. I have also compared the source of the PC version to the Hbx sniffed mechanism, and they dont match, but i dont know how current that source was.

Andrew