I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??
On Monday, 27 December 2021 at 17:35:39 UTC-5, StarDust wrote:
On Monday, December 27, 2021 at 10:36:51 AM UTC-8, RichA wrote:More like 5 or less.
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??What were you expecting?
Zero?
🤔
On Monday, December 27, 2021 at 10:36:51 AM UTC-8, RichA wrote:
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??What were you expecting?
Zero?
🤔
On Monday, December 27, 2021 at 7:23:28 PM UTC-8, RichA wrote:
On Monday, 27 December 2021 at 17:35:39 UTC-5, StarDust wrote:Vixen GPDX mount gets less than 5
On Monday, December 27, 2021 at 10:36:51 AM UTC-8, RichA wrote:More like 5 or less.
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??What were you expecting?
Zero?
🤔
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??
On 27/12/2021 18:36, RichA wrote:
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??
Most are operated on closed loop guiding so provided that it is regular
and systematic the periodic error can be corrected out. The main PEC >component can be trained out by lookup table in some circumstances.
Why make the mechanical precision so much more difficult and expensive
to manufacture when CCD autoguiders are cheap and getting cheaper?
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??
On Monday, 27 December 2021 at 22:39:06 UTC-5, StarDust wrote:
On Monday, December 27, 2021 at 7:23:28 PM UTC-8, RichA wrote:Pretty good given the gear size.
On Monday, 27 December 2021 at 17:35:39 UTC-5, StarDust wrote:Vixen GPDX mount gets less than 5
On Monday, December 27, 2021 at 10:36:51 AM UTC-8, RichA wrote:More like 5 or less.
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??What were you expecting?
Zero?
🤔
On Tue, 28 Dec 2021 21:31:11 +0000, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:
On 27/12/2021 18:36, RichA wrote:
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??
Most are operated on closed loop guiding so provided that it is regular
and systematic the periodic error can be corrected out. The main PEC >component can be trained out by lookup table in some circumstances.
Why make the mechanical precision so much more difficult and expensiveLately, the best mounts have included absolute encoders with
to manufacture when CCD autoguiders are cheap and getting cheaper?
sub-arcsecond precision, so mechanical errors in the drive system
don't even need to be regular or systematic!
On Tuesday, 28 December 2021 at 17:07:57 UTC-5, Chris L Peterson wrote:
On Tue, 28 Dec 2021 21:31:11 +0000, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:
On 27/12/2021 18:36, RichA wrote:Lately, the best mounts have included absolute encoders with
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??
Most are operated on closed loop guiding so provided that it is regular
and systematic the periodic error can be corrected out. The main PEC
component can be trained out by lookup table in some circumstances.
Why make the mechanical precision so much more difficult and expensive
to manufacture when CCD autoguiders are cheap and getting cheaper?
sub-arcsecond precision, so mechanical errors in the drive system
don't even need to be regular or systematic!
Yes, it increases the price of mount by at least a 1/3 to have those encoders.
On Fri, 31 Dec 2021 09:37:51 -0800 (PST), RichA <rande...@gmail.com>
wrote:
On Tuesday, 28 December 2021 at 17:07:57 UTC-5, Chris L Peterson wrote:
On Tue, 28 Dec 2021 21:31:11 +0000, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:
On 27/12/2021 18:36, RichA wrote:Lately, the best mounts have included absolute encoders with
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??
Most are operated on closed loop guiding so provided that it is regular >> >and systematic the periodic error can be corrected out. The main PEC
component can be trained out by lookup table in some circumstances.
Why make the mechanical precision so much more difficult and expensive
to manufacture when CCD autoguiders are cheap and getting cheaper?
sub-arcsecond precision, so mechanical errors in the drive system
don't even need to be regular or systematic!
Yes, it increases the price of mount by at least a 1/3 to have those encoders.The price is dropping. In ten years such control systems will be
routine on most decent mounts. It's the obvious way to go.
On Friday, 31 December 2021 at 13:34:13 UTC-5, Chris L Peterson wrote:
On Fri, 31 Dec 2021 09:37:51 -0800 (PST), RichA <rande...@gmail.com>
wrote:
On Tuesday, 28 December 2021 at 17:07:57 UTC-5, Chris L Peterson wrote:The price is dropping. In ten years such control systems will be
On Tue, 28 Dec 2021 21:31:11 +0000, Martin Brown
<'''newspam'''@nonad.co.uk> wrote:
On 27/12/2021 18:36, RichA wrote:Lately, the best mounts have included absolute encoders with
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??
Most are operated on closed loop guiding so provided that it is regular >> >> >and systematic the periodic error can be corrected out. The main PEC
component can be trained out by lookup table in some circumstances.
Why make the mechanical precision so much more difficult and expensive >> >> >to manufacture when CCD autoguiders are cheap and getting cheaper?
sub-arcsecond precision, so mechanical errors in the drive system
don't even need to be regular or systematic!
Yes, it increases the price of mount by at least a 1/3 to have those encoders.
routine on most decent mounts. It's the obvious way to go.
Telescope ones must be quite high-end as you can buy absolute encoders for small robots for $10.00, which technically is
cheaper than the old HP rotary encoders.
On Sat, 1 Jan 2022 23:20:23 -0800 (PST), RichA <rande...@gmail.com>
wrote:
On Friday, 31 December 2021 at 13:34:13 UTC-5, Chris L Peterson wrote:
On Fri, 31 Dec 2021 09:37:51 -0800 (PST), RichA <rande...@gmail.com>
wrote:
On Tuesday, 28 December 2021 at 17:07:57 UTC-5, Chris L Peterson wrote: >> >> On Tue, 28 Dec 2021 21:31:11 +0000, Martin BrownThe price is dropping. In ten years such control systems will be
<'''newspam'''@nonad.co.uk> wrote:
On 27/12/2021 18:36, RichA wrote:Lately, the best mounts have included absolute encoders with
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real??
Most are operated on closed loop guiding so provided that it is regular
and systematic the periodic error can be corrected out. The main PEC >> >> >component can be trained out by lookup table in some circumstances.
Why make the mechanical precision so much more difficult and expensive >> >> >to manufacture when CCD autoguiders are cheap and getting cheaper?
sub-arcsecond precision, so mechanical errors in the drive system
don't even need to be regular or systematic!
Yes, it increases the price of mount by at least a 1/3 to have those encoders.
routine on most decent mounts. It's the obvious way to go.
Telescope ones must be quite high-end as you can buy absolute encoders for small robots for $10.00, which technically isAbsolute encoders with several hundred thousand count resolution still
cheaper than the old HP rotary encoders.
run hundreds of dollars, which obviously adds a lot to the cost.
There's a workaround using lower resolution encoders with gear systems
to get the high count. This requires precision gears, but they are low
torque and preloaded, which makes them much less expensive than
precision ground drive gears.
On Sunday, 2 January 2022 at 08:44:54 UTC-5, Chris L Peterson wrote:
On Sat, 1 Jan 2022 23:20:23 -0800 (PST), RichA <rande...@gmail.com>
wrote:
On Friday, 31 December 2021 at 13:34:13 UTC-5, Chris L Peterson wrote:Absolute encoders with several hundred thousand count resolution still
On Fri, 31 Dec 2021 09:37:51 -0800 (PST), RichA <rande...@gmail.com>
wrote:
On Tuesday, 28 December 2021 at 17:07:57 UTC-5, Chris L Peterson wrote: >> >> >> On Tue, 28 Dec 2021 21:31:11 +0000, Martin BrownThe price is dropping. In ten years such control systems will be
<'''newspam'''@nonad.co.uk> wrote:
On 27/12/2021 18:36, RichA wrote:Lately, the best mounts have included absolute encoders with
I'm seeing PE of 10 arc seconds, on $4000+ mounts? Is that real?? >> >> >> >Most are operated on closed loop guiding so provided that it is regular
and systematic the periodic error can be corrected out. The main PEC >> >> >> >component can be trained out by lookup table in some circumstances. >> >> >> >
Why make the mechanical precision so much more difficult and expensive
to manufacture when CCD autoguiders are cheap and getting cheaper?
sub-arcsecond precision, so mechanical errors in the drive system
don't even need to be regular or systematic!
Yes, it increases the price of mount by at least a 1/3 to have those encoders.
routine on most decent mounts. It's the obvious way to go.
Telescope ones must be quite high-end as you can buy absolute encoders for small robots for $10.00, which technically is
cheaper than the old HP rotary encoders.
run hundreds of dollars, which obviously adds a lot to the cost.
There's a workaround using lower resolution encoders with gear systems
to get the high count. This requires precision gears, but they are low
torque and preloaded, which makes them much less expensive than
precision ground drive gears.
Part of the reason I believe we pay so much for this stuff is that they are (like most machine parts like bearings) mostly
designed for endurance at high RPM's. Which isn't what telescope drives/mounts are. Pity.
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