#APCC #APCC


Rouz
 

One side of the model  much better than the other?


Rouz
 

I've made a model with equal points in the East and West.

OTA is a pretty rigid CDK12.5 on a pier and I've tried to minimize any source of flex.

For some reason the West model is always much better than the East one.  This last one has an rms error of about 10x less.

As expected, tracking west of the pier is better than the east side.

Is this indicating flex in the system or is it something else?


Bill Long
 

Are you neutral balanced in both axis?


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Rouz <rbidshahri@...>
Sent: Thursday, September 16, 2021 12:11 AM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] #APCC
 
I've made a model with equal points in the East and West.

OTA is a pretty rigid CDK12.5 on a pier and I've tried to minimize any source of flex.

For some reason the West model is always much better than the East one.  This last one has an rms error of about 10x less.

As expected, tracking west of the pier is better than the east side.

Is this indicating flex in the system or is it something else?


Rouz
 

Yes I believe so. Disengaged the worms and fine tuned the balance in all axis.

I'm wondering if that actually is the best thing to do? Perhaps a slight bias might ensure the gears are meshed better, but these CP4 do have spring loaded worms.

-Rouz


Ray Gralak
 

For some reason the West model is always much better than the East one. This last one has an rms error of
about 10x less.
When using Dec-Arcs it is important to realize that the all-sky pointing terms may not be very accurate.

For APCC to calculate accurate pointing-terms it needs to have points distributed throughout a larger portion of the sky than a narrow band.

As expected, tracking west of the pier is better than the east side.

Is this indicating flex in the system or is it something else?
It's an indication of more randomness in the data. This can be caused by moving optics, tugging cables, and inaccurate plate solves, etc.

-Ray

-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Rouz
Sent: Thursday, September 16, 2021 12:12 AM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] #APCC

I've made a model with equal points in the East and West.

OTA is a pretty rigid CDK12.5 on a pier and I've tried to minimize any source of flex.

For some reason the West model is always much better than the East one. This last one has an rms error of
about 10x less.

As expected, tracking west of the pier is better than the east side.

Is this indicating flex in the system or is it something else?


Bill Long
 

Well its probably not related to what you are seeing, but the freshest guidance from AP has been to neutral balance. I made that change on my Mach 2 + AG 12.5" rig, and it definitely guided much better as a result. 


From: main@ap-gto.groups.io <main@ap-gto.groups.io> on behalf of Rouz <rbidshahri@...>
Sent: Thursday, September 16, 2021 12:39 AM
To: main@ap-gto.groups.io <main@ap-gto.groups.io>
Subject: Re: [ap-gto] #APCC
 
Yes I believe so. Disengaged the worms and fine tuned the balance in all axis.

I'm wondering if that actually is the best thing to do? Perhaps a slight bias might ensure the gears are meshed better, but these CP4 do have spring loaded worms.

-Rouz


Roland Christen
 


Perhaps a slight bias might ensure the gears are meshed better
No, false. Gears do not mesh better with an off-balance bias.

Rolando


-----Original Message-----
From: Rouz <rbidshahri@...>
To: main@ap-gto.groups.io
Sent: Thu, Sep 16, 2021 2:39 am
Subject: Re: [ap-gto] #APCC

Yes I believe so. Disengaged the worms and fine tuned the balance in all axis.

I'm wondering if that actually is the best thing to do? Perhaps a slight bias might ensure the gears are meshed better, but these CP4 do have spring loaded worms.

-Rouz

--
Roland Christen
Astro-Physics


Rouz
 

On Thu, Sep 16, 2021 at 04:50 AM, Ray Gralak wrote:

Hi Ray, 

Ok will try an all-sky model soon.

I don't have much in the south but even that with the 3 x 3 degree point spacing ends up with 1500 points which is not feasible.

I remember you mentioned something with 400 points should work well.  I'll adjust the spacing to get something in that ballpark.

I'm assuming its more important to have the Ra points closer together than the Dec?

-Rouz





Rouz
 

Hi Roland,

Yes that's what I thought, its is fine balanced.

I remember with my old Losmandy mounts bias was usually better but I feel no backlash with these CP4 worms. That was one of the main reasons I went for the CP4!