Eq8 or CEM120

[bluesilver]

Can i ask, how are you driving this mount?  are you using EQMOD?

Will be good to here what you think of this mount as i am looking at either the EQ8-R or the EQ8-RH

 

[Nigella Bryant]

3 minutes ago, bluesilver said:

Can i ask, how are you driving this mount?  are you using EQMOD?

Will be good to here what you think of this mount as i am looking at either the EQ8-R or the EQ8-RH

 

I'm using Cart de Ciel and Eqmod. 

[tonyowens_uk]

Nigella if you have not already looked at GSS as an alternative to EQMOD for controlling your new EQ8R, it would be worthwhile. There is a discussion list for GSS here: https://gss.groups.io/g/main

GSS is in active development (it was originally developed to work around some of the EQ8's limitations, which it does rather well) with meaningful new functionality still appearing. You will no doubt have a large list of issues to work through with your 12" imaging Newt on your new EQ8R to get it operating reliably at the expected performance level, but when you get that under control, best have a look at GSS.

Tony  

[MikeP]

Hi Tony,

I have a new EQ8-R.  What specifically are the advantages of GSS over EQMOD?  Its user interface is much more modern but that aside, I couldn't see anything that made me want to switch.  I've used EQMOD since its early days and so perhaps I am just biased.

Mike

[scotty38]

2 hours ago, MikeP said:

Hi Tony,

I have a new EQ8-R.  What specifically are the advantages of GSS over EQMOD?  Its user interface is much more modern but that aside, I couldn't see anything that made me want to switch.  I've used EQMOD since its early days and so perhaps I am just biased.

Mike

When I mess up and wonder why I cannot see anything the 3D scope view confirms my idiocy or the genuine error. That's worth it for me lol 🙂 🙂 

[Nigella Bryant]

17 hours ago, tonyowens_uk said:

Nigella if you have not already looked at GSS as an alternative to EQMOD for controlling your new EQ8R, it would be worthwhile. There is a discussion list for GSS here: https://gss.groups.io/g/main

GSS is in active development (it was originally developed to work around some of the EQ8's limitations, which it does rather well) with meaningful new functionality still appearing. You will no doubt have a large list of issues to work through with your 12" imaging Newt on your new EQ8R to get it operating reliably at the expected performance level, but when you get that under control, best have a look at GSS.

Tony  

Thanks Tony, I've not investigated GSS as of yet because I've used Eqmod for years with my old Neq6. I've still not got good polar alignment as of yet and the awful weather combination with life hasn't allowed me to do drift alignment. Everything else is working well. It can't believe I bought this mount end of September but not got it completely set up yet. Maybe initial setup as with space telescopes do take months to first light, lol. 

[tonyowens_uk]

13 hours ago, MikeP said:

Hi Tony,

I have a new EQ8-R.  What specifically are the advantages of GSS over EQMOD?  Its user interface is much more modern but that aside, I couldn't see anything that made me want to switch.  I've used EQMOD since its early days and so perhaps I am just biased.

Mike

Hi Mike,

Three examples of differences in favour of GSS v. EQMOD are:

1. If you use the integral PPEC on the EQ8 or EQ8R, I believe that incoming autoguider move commands that coincide with a PPEC 'bin' transition are ignored, which negatively affects guiding accuracy. This happens with EQMOD controlling EQ8, due to a design flaw in the EQ8's firmware design. My understanding is that this also happens with the newer EQ8 firmware versions (cross-compiled for the STM32 that runs the EQ8 motion controller). In GSS there is a workaround.

2. Very short autoguide corrections sent to either EQ8 or EQ8R are executed very rapidly in GSS using GoTo moves. EQMOD has nothing comparable.

3. EQMOD is not in active development. GSS has at least three intermittently active developers and a growing user base

You can read about the first two of these issues on the GSS forum I hotlinked in my earlier post, if interested.

Best

 

Tony Owens

[MikeP]

Hi Tony,

Thank you for your response.  I've replaced my obsy and  just about all my obsy equipment after a bit of a hiatus, so I was reluctant to move away from some semblance of familiarity i.e. EQMOD.

I didn't really understand what you have written in the first bullet. What I take from it is that if I use PPEC alongside PHD2, there could / would be clashes.  Since I wasn't planning to look at PPEC for the foreseeable, I won't worry about that but I won't forget the issue .

I had read somewhere that GSS sends GoTo commands rather than the varying length pulses that EQMOD uses.  In a digital world that makes sense as does using software that is being further developed.  

Once I have everything working with EQMOD, I will have a look at GSS and possibly PPEC.

Could you point me to where in the GSS EQ8 group that the first two bullet points are discussed.  I had already joined the group but can't find what you are referring to.

Thank you again.

Mike

[Neil27]

14 hours ago, Nigella Bryant said:

Thanks Tony, I've not investigated GSS as of yet because I've used Eqmod for years with my old Neq6. I've still not got good polar alignment as of yet and the awful weather combination with life hasn't allowed me to do drift alignment. Everything else is working well. It can't believe I bought this mount end of September but not got it completely set up yet. Maybe initial setup as with space telescopes do take months to first light, lol. 

I know the feeling Nigella, since buying my mount in May 2021, I have only just accurately polar aligned using sharp cap  over Christmas. The struggle against RL and clouds can be an issue.

[tonyowens_uk]

54 minutes ago, MikeP said:

Hi Tony,

Thank you for your response.  I've replaced my obsy and  just about all my obsy equipment after a bit of a hiatus, so I was reluctant to move away from some semblance of familiarity i.e. EQMOD.

I didn't really understand what you have written in the first bullet. What I take from it is that if I use PPEC alongside PHD2, there could / would be clashes.  Since I wasn't planning to look at PPEC for the foreseeable, I won't worry about that but I won't forget the issue .

I had read somewhere that GSS sends GoTo commands rather than the varying length pulses that EQMOD uses.  In a digital world that makes sense as does using software that is being further developed.  

Once I have everything working with EQMOD, I will have a look at GSS and possibly PPEC.

Could you point me to where in the GSS EQ8 group that the first two bullet points are discussed.  I had already joined the group but can't find what you are referring to.

Thank you again.

Mike

Hi Mike. I agree with you about combining PPEC with properly-refined autoguiding - I've never seen a clear benefit myself in the case of EQ8's. What works for me extemely well (using the original motor board/motors used in the original EQ8 and antibacklasg gears) is very frequent small corrections, with a predictive guiding algo from PHD2.  With the much improved motor board that appeared with the mount refresh, the picture is likely to be different because of the more refined microstepping behaviour, and I havent investigated that yet.

Re references to the 'under the hood' EQ8-specific investigations and improvements built into GSS, I suggest you search for contributions from Andrew Johansen in particular.

cheers

Tony Owens

[MikeP]

19 minutes ago, tonyowens_uk said:

I suggest you search for contributions from Andrew Johansen in particular.

Thanks Tony.  Will do.

Mike