Date   

Re: [ap-ug] Faint galaxies in Pisces

ayiomamitis
 

Rolando,

Very nice and rich image. Any possibility of RGB being added or is the light pollution prohibitive for colour?

My local pollution has seriously gotten out of hand and in spite of very good seeing at home.  :-(

Anthony.


On 27-Oct-17 23:26, chris1011@... [ap-ug] wrote:
 

Hi All,

In my on-going testing of tracking/modeling software I did some exposures of a faint group of galaxies centered around NGC507. This group is just north of M33 and individual galaxies range from Mag 12 to around mag 16. I could not get any fainter due to severe light pollution at my observatory, and it isn't getting any better unfortunately. This image is a stack of 10 x 600 sec exposures with 17" F8 AP Astrograph, STL11K camera. Inverted to show the faintest members:

https://www.astromart.com/common/image_popup.asp?image=/images/forums/836000-836999/836272.jpg&caption=

Normal light image:
https://www.astromart.com/common/image_popup.asp?image=/images/forums/836000-836999/836271.jpg&caption=

Rolando



Faint galaxies in Pisces

Roland Christen
 

Hi All,

In my on-going testing of tracking/modeling software I did some exposures of a faint group of galaxies centered around NGC507. This group is just north of M33 and individual galaxies range from Mag 12 to around mag 16. I could not get any fainter due to severe light pollution at my observatory, and it isn't getting any better unfortunately. This image is a stack of 10 x 600 sec exposures with 17" F8 AP Astrograph, STL11K camera. Inverted to show the faintest members:

https://www.astromart.com/common/image_popup.asp?image=/images/forums/836000-836999/836272.jpg&caption=

Normal light image:
https://www.astromart.com/common/image_popup.asp?image=/images/forums/836000-836999/836271.jpg&caption=

Rolando


Re: strange electrical issue - anyone have any knowledge of what to do.

Christopher Erickson
 

I have carefully checked out the suspicious Pyramid 15A power supply and as of right now, it is working as designed.
 
Yesterday, after a careful visual inspection and testing many components with a multimeter, I powered it up and noted that it was putting out a clean 13.80 volts.  Wiggling and tapping various components with a plastic rod did not disrupt operation.  I then attached a 4A load and observed it for 8 hours.  As it heated up, the voltage out drifted from 13.80V to 13.84V.  Not enough to be concerned about.
 
So as of right now, I can't find any problem with this power supply.  That doesn't mean that it doesn't has some kind of intermittent problem that I have not yet detected.  Maybe the ride through the mail jarred something in a good way. Or at least sort of in a good way.
 
NOTES:
 
* 100% made in China.
* All components were of non-brand-name Chinese origin.
* Build quality - reasonably good.
* All screws and bolts inside were sealed with drops of a red locking compound.
* All switches, indicators and such were were anchored in place with a yellow potting compound.
* Big filter caps weren't potted.
* Very old-school LM723 voltage regulator chip design.
* Old design is about 50-60% efficient.  Lots of electricity converted to waste heat.
* Absolutely identical down to the last nut and bolt to a Tripp-Lite 10A power supply I had sitting around.
* I wouldn't load this 15A power supply with more than about 4A continuous load.
* Has overheat protection provided by an appliance-grade thermal cutoff commonly found in coffee makers.
* Overcurrent protection indirectly provided by the appliance thermal cutoff.
* Design is not protected from dead shorts across the output.
* Chassis frame connected to the negative side of the DC output and the 120V power cord ground wire.
* NOT UL listed.
* NOT CE marked.
* Does NOT meet Energy-Star efficiency requirements.
 
 
 
-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com
 



From: Christopher Erickson [mailto:christopher.k.erickson@...]
Sent: Thursday, October 26, 2017 12:14 AM
To: 'ap-gto@...'
Subject: RE: [ap-gto] strange electrical issue - anyone have any knowledge of what to do.

I have received Woody's defective power supply and will check it out tomorrow.
 
 
-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com
 


From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, October 21, 2017 2:58 PM
To: ap-gto@...
Subject: RE: [ap-gto] strange electrical issue - anyone have any knowledge of what to do.

Christopher,

 

Yes, I did check all cables.  And they are all good (except for the ones that melted).  And besides, they all work with other power supplies, just not with this one.

 

You’ll see my comments in a previous post.  The photo Jimmy posted of his PC board is different than mine in several ways.  It’s just plain a different board.  I don’t know if mine is newer or older than his.  But it’s different.  Same model number on the PS.

 

Woody

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, October 21, 2017 5:18 PM
To: ap-gto@...
Subject: RE: [ap-gto] strange electrical issue - anyone have any knowledge of what to do.

 

 

We'll find out!

 

I'll use a test load and carefully monitor current and temperatures.

 

Thermal paste under power transistors is common.

 

If things got hot really fast I would also be tempted to double-check your wires and connections between the power supply and the CP4 (and whatever else was hooked to that PS) to make sure there aren't any shorts anyplace.

 

 

-Christopher Erickson
Observatory engineer
Summit Kinetics

Waikoloa, HI 96738
www.summitkinetics.com

 

 


From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, October 21, 2017 1:45 PM
To: ap-gto@...
Subject: RE: [ap-gto] strange electrical issue - anyone have any knowledge of what to do.

Christopher,

 

I don't think that's the case with mine as it was brand new and never before used.  It "fried" things the first time I hooked it up.

 

But now you've got me wondering if mine even has that compound.  I don't recall seeing it at the bases of the caps.  I do recall seeing some brightly colored paint or grease-like stuff under some of the transistors.  I figured it was thermal paste of some kind to aid heat transfer.

 

I'll have to wait until it arrives in Hawaii to learn if mine even has that stuff under the caps.

 

Woody

.

-----Original Message-----
From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, October 21, 2017 1:58 PM
To: ap-gto@...
Subject: RE: [ap-gto] strange electrical issue - anyone have any knowledge of what to do.

 

I have to wonder if the Pyramid power supplies that have failed in the past couple of years that we have heard about so far, are specifically because of this vibration-caused, failed cap issue.

 

It is the type of delayed-failure that would not be detected by routine assembly-line QC testing.

 

It might be interesting if people who owned these power supplies would all open the cases and look for the potting compound around their caps and note the approximate date when they received their power supplies.

 

 

-Christopher Erickson
Observatory engineer
Summit Kinetics

Waikoloa, HI 96738
www.summitkinetics.com

 

 


From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, October 21, 2017 10:19 AM
To: ap-gto@...
Subject: RE: [ap-gto] strange electrical issue - anyone have any knowledge of what to do.

I noticed that too but wasn’t sure what it was. I just re-read the original post and this is the good working board. So looking visually wouldn’t have done anything anyway.

But I did learn something today…I’ll mark the calander……if I can find it….

-Steve

From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, October 21, 2017 4:05 PM
To: ap-gto@...
Subject: RE: [ap-gto] strange electrical issue - anyone have any knowledge of what to do.

 

That is definitely a hard potting compound and not leakage from the caps.
It was manually applied after the board was assembled. You can see where a
tiny bit was dribbled on the left top of the 330 Ohm resistor
(orange-orange-brown-gold bands) just beneath and to the left side of the
three caps.

Electrolytic caps are dry and don't have any fluids or glues inside. They
are basically two long, thin conductive plates with a couple of insulator
sheets between them that has been wrapped up tight like a roll of toilet
paper and then stuffed into a protective can with a rubber plug. The cross
pattern on the top of the cans are designed to rupture at low pressure,
allowing a failing cap to vent hot gasses before they build up to explosive
pressure levels.

The fact that those three caps are potted tells me that at one point Pyramid
started having problems with excessive cap failures in their power supplies
due to transformer vibration coupling.

I'll bet there was a lot of angst at Pyramid before they finally figured out
that problem and also an expedient fix.

At some point they must have switched suppliers of the caps and the new caps
were more fragile. That's quite common with counterfeit parts, although
that doesn't definitively mean the caps are counterfeits.

Personally I would have instead decided it was an excellent excuse to bite
the bullet and upgrade the whole power supply design with more modern
technology and components.

And also time to start only buying electronic components from distributors
that have implemented certified component programs and associated
guarantees.

-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com

-----Original Message-----
From: ap-gto@... [mailto:ap-gto@...]
Sent: Saturday, October 21, 2017 9:02 AM
To: ap-gto@...
Subject: RE: [ap-gto] strange electrical issue - anyone have any knowledge
of what to do.

The 4700mf 25 volt cap looks like to it has leaked out badly along with 2
other caps nearby C3

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Re: Update to odd tracking/RA behavior

Roland Christen
 


Have you checked how much current is being drawn from the 5 amp supply?
Our mounts typically draw less than 800 milliamps during tracking.

Rolando


-----Original Message-----
From: 'Joseph Zeglinski' J.Zeglinski@... [ap-gto]
To: ap-gto
Sent: Fri, Oct 27, 2017 12:06 pm
Subject: Re: [ap-gto] Update to odd tracking/RA behavior



Mike,
 
    Assuming you replaced the original  PS with a new “PYRAMID PS-9KX” (13.8 vdc @ 5 amp steady current,  & 7 amp max), its 4-page document says:
(5)   THIS UNIT HAS ELECTRONIC OVERLOAD PROTECTION WITH INSTANT AUTOMATIC RESET FUNCTION.
IF OUTPUT IS OVERLOADED - THE OUTPUT POWER WILL
AUTOMATICALLY SHUT OFF
RELEASE POWER CORD OF YOUR EQUIPMENT FROM
THE OUTPUT TERMINALS AND CHECK THE ACTUAL
POWER RATING OF YOUR
EQUIPMENT.  THIS UNIT WILL    “AUTOMATICALLY  RESET  INSTANTLY”
(6)  OVER TEMPERATURE PROTECTION CIRCUITRY IS USED IN PS-9KX TO PREVENT OVER HEAT DAMAGE.
UNIT WILL BE SHUT DOWN  ... 
AFTER 15 MINUTES ( MIN) AT 100% RATED LOAD
AND
  AFTER  25 MINUTES ( MIN ) AT 80% OF RATED LOAD
 
    Have you checked how much current is being drawn from the 5 amp supply? If you are using only 80% of rated amps, this 4 amp power drain can cause a momentary power loss at the 25 minute mark at this level – even sooner, at the end of 15 minutes,  if it supplies its “full rated”  5 amps for 15 minutes.
 
    It will recover automatically, as soon as it cools off, so you will never know if there was a power glitch, except for those trailing star images.
I had it fool me once when the AP-900 seemed to be running just fine. Then it lost power during “one of its MANY slews”,  after more than an hour of (apparently) normal operation. As I was looking for the cause of the system power loss, it came back to life all on its own, and slewed the OTA into the pier before I got to it. So, I assume my scope system (mount and STL) were running at even less than the rated 80% trip level, and it then glitched much later,  at 4 times their warning period. So, even operating at less than 80% power drain is not reliable – just takes longer to fail.
 
    Seems it likes to run at much less than advertised amps – probably just 3.5 amps continuously, where it won’t crow-bar, some time during the night – then come back like nothing had happened. I wonder if the design would have been safer to just shut itself down, in the case of powering motors. That’s why I stopped using my PYRAMID supplies – can’t trust them to not screw things up, dangerously.
 
    I wonder if this” power dip and auto recovery” ...  is what you are experiencing. Check your amps,
and get a larger rated PYRAMID, perhaps the 10 amp would be safer. Even every production unit of the same supply,  can differ, so your presently “better performance” may have a longer trip time, with a faster auto recovery, than the previous PS.
 
Joe



Re: Update to odd tracking/RA behavior

Roland Christen
 

I don't think the power supply is your problem. I still say it's something mechanical. You say that it's in the RA axis, correct? Then i would do a simple tracking test to determine if the RA axis is tracking smoothly for long periods of time. Tracking, not guiding. Here's how I would do this:

1) offset your azimuth axis by a couple of degrees so that the RA will drift.
2) aim the scope at the celestial equator
3) turn on your PE correction
4) take a 1/2 hour exposure or even up to 1 hour exposure.

The above is a classic tried and true method to characterize your RA axis tracking (something that is forgotten in today's computerized world).

You will get a series star trails. These trails will tell you everything you need to know about how well the RA axis is tracking, and whether during that time you are getting any sudden jumps in RA. The beauty of this test is that it eliminates everything but the raw tracking ability of the mount in RA.

I have experienced a sudden movement of some 20 arc seconds during a guiding test on my observatory mount. Fortunately three of us were looking at the screen when it happened. The guider box received a cosmic ray hit that was off center and very bright. This fooled the guider software into thinking that the guide star had moved and proceeded to send a large correction signal to the mount. This sort of thing can happen at any time during guiding and there is really no solution.

Assuming that it is not a cosmic ray hit, you might want to check the tightness of the spur gears in the reduction gearbox. If the center gear is adjusted too tightly against the two mating gears, you can have the possibility of erratic tracking. Please check to see if the geartrain has a small amount of clearance so that it moves smoothly. You should not try to eliminate all backlash to the point where the gears are binding.

Rolando



-----Original Message-----
From: 'Mike Shade' mshade@q.com [ap-gto]
To: ap-gto
Sent: Fri, Oct 27, 2017 12:17 pm
Subject: RE: [ap-gto] Update to odd tracking/RA behavior

The power supply that I was using was an old Radio Shack unit, 13.8V 10A unit...I replaced it with the Pyramid. All I am running on it is the 1600GTO slewing at 600X.



If the pyramid is a unreliable unit, what power supplies are people using. Again, this only powers the mount. I bought this through AP a few years ago, seldom used. It powered my 1200GTO occasionally.



Thanks...



Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com



In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west. Can it be half

a year since I watched her April rising in the east? Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights



International Dark Sky Association: <http://www.darksky.org/> www.darksky.org



From: ap-gto@... [mailto:ap-gto@...]
Sent: Friday, October 27, 2017 10:03 AM
To: ap-gto@...
Subject: Re: [ap-gto] Update to odd tracking/RA behavior





Mike,



Assuming you replaced the original PS with a new “PYRAMID PS-9KX” (13.8 vdc @ 5 amp steady current, & 7 amp max), its 4-page document says:

(5) THIS UNIT HAS ELECTRONIC OVERLOAD PROTECTION WITH INSTANT AUTOMATIC RESET FUNCTION.
IF OUTPUT IS OVERLOADED - THE OUTPUT POWER WILL AUTOMATICALLY SHUT OFF
RELEASE POWER CORD OF YOUR EQUIPMENT FROM THE OUTPUT TERMINALS AND CHECK THE ACTUAL
POWER RATING OF YOUR EQUIPMENT. THIS UNIT WILL “AUTOMATICALLY RESET INSTANTLY”

(6) OVER TEMPERATURE PROTECTION CIRCUITRY IS USED IN PS-9KX TO PREVENT OVER HEAT DAMAGE.
UNIT WILL BE SHUT DOWN ... AFTER 15 MINUTES ( MIN) AT 100% RATED LOAD
AND AFTER 25 MINUTES ( MIN ) AT 80% OF RATED LOAD



Have you checked how much current is being drawn from the 5 amp supply? If you are using only 80% of rated amps, this 4 amp power drain can cause a momentary power loss at the 25 minute mark at this level – even sooner, at the end of 15 minutes, if it supplies its “full rated” 5 amps for 15 minutes.



It will recover automatically, as soon as it cools off, so you will never know if there was a power glitch, except for those trailing star images.

I had it fool me once when the AP-900 seemed to be running just fine. Then it lost power during “one of its MANY slews”, after more than an hour of (apparently) normal operation. As I was looking for the cause of the system power loss, it came back to life all on its own, and slewed the OTA into the pier before I got to it. So, I assume my scope system (mount and STL) were running at even less than the rated 80% trip level, and it then glitched much later, at 4 times their warning period. So, even operating at less than 80% power drain is not reliable – just takes longer to fail.



Seems it likes to run at much less than advertised amps – probably just 3.5 amps continuously, where it won’t crow-bar, some time during the night – then come back like nothing had happened. I wonder if the design would have been safer to just shut itself down, in the case of powering motors. That’s why I stopped using my PYRAMID supplies – can’t trust them to not screw things up, dangerously.



I wonder if this” power dip and auto recovery” ... is what you are experiencing. Check your amps,

and get a larger rated PYRAMID, perhaps the 10 amp would be safer. Even every production unit of the same supply, can differ, so your presently “better performance” may have a longer trip time, with a faster auto recovery, than the previous PS.



Joe





[Non-text portions of this message have been removed]



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Posted by: "Mike Shade" <mshade@q.com>
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Re: Update to odd tracking/RA behavior

Mike Shade
 

The power supply that I was using was an old Radio Shack unit, 13.8V 10A unit...I replaced it with the Pyramid. All I am running on it is the 1600GTO slewing at 600X.



If the pyramid is a unreliable unit, what power supplies are people using. Again, this only powers the mount. I bought this through AP a few years ago, seldom used. It powered my 1200GTO occasionally.



Thanks...



Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com



In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west. Can it be half

a year since I watched her April rising in the east? Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights



International Dark Sky Association: <http://www.darksky.org/> www.darksky.org



From: ap-gto@... [mailto:ap-gto@...]
Sent: Friday, October 27, 2017 10:03 AM
To: ap-gto@...
Subject: Re: [ap-gto] Update to odd tracking/RA behavior





Mike,



Assuming you replaced the original PS with a new “PYRAMID PS-9KX” (13.8 vdc @ 5 amp steady current, & 7 amp max), its 4-page document says:

(5) THIS UNIT HAS ELECTRONIC OVERLOAD PROTECTION WITH INSTANT AUTOMATIC RESET FUNCTION.
IF OUTPUT IS OVERLOADED - THE OUTPUT POWER WILL AUTOMATICALLY SHUT OFF
RELEASE POWER CORD OF YOUR EQUIPMENT FROM THE OUTPUT TERMINALS AND CHECK THE ACTUAL
POWER RATING OF YOUR EQUIPMENT. THIS UNIT WILL “AUTOMATICALLY RESET INSTANTLY”

(6) OVER TEMPERATURE PROTECTION CIRCUITRY IS USED IN PS-9KX TO PREVENT OVER HEAT DAMAGE.
UNIT WILL BE SHUT DOWN ... AFTER 15 MINUTES ( MIN) AT 100% RATED LOAD
AND AFTER 25 MINUTES ( MIN ) AT 80% OF RATED LOAD



Have you checked how much current is being drawn from the 5 amp supply? If you are using only 80% of rated amps, this 4 amp power drain can cause a momentary power loss at the 25 minute mark at this level – even sooner, at the end of 15 minutes, if it supplies its “full rated” 5 amps for 15 minutes.



It will recover automatically, as soon as it cools off, so you will never know if there was a power glitch, except for those trailing star images.

I had it fool me once when the AP-900 seemed to be running just fine. Then it lost power during “one of its MANY slews”, after more than an hour of (apparently) normal operation. As I was looking for the cause of the system power loss, it came back to life all on its own, and slewed the OTA into the pier before I got to it. So, I assume my scope system (mount and STL) were running at even less than the rated 80% trip level, and it then glitched much later, at 4 times their warning period. So, even operating at less than 80% power drain is not reliable – just takes longer to fail.



Seems it likes to run at much less than advertised amps – probably just 3.5 amps continuously, where it won’t crow-bar, some time during the night – then come back like nothing had happened. I wonder if the design would have been safer to just shut itself down, in the case of powering motors. That’s why I stopped using my PYRAMID supplies – can’t trust them to not screw things up, dangerously.



I wonder if this” power dip and auto recovery” ... is what you are experiencing. Check your amps,

and get a larger rated PYRAMID, perhaps the 10 amp would be safer. Even every production unit of the same supply, can differ, so your presently “better performance” may have a longer trip time, with a faster auto recovery, than the previous PS.



Joe





[Non-text portions of this message have been removed]


Re: Update to odd tracking/RA behavior

Joe Zeglinski
 

Mike,
 
    Assuming you replaced the original  PS with a new “PYRAMID PS-9KX” (13.8 vdc @ 5 amp steady current,  & 7 amp max), its 4-page document says:

(5)   THIS UNIT HAS ELECTRONIC OVERLOAD PROTECTION WITH INSTANT AUTOMATIC RESET FUNCTION.
IF OUTPUT IS OVERLOADED - THE OUTPUT POWER WILL
AUTOMATICALLY SHUT OFF
RELEASE POWER CORD OF YOUR EQUIPMENT FROM
THE OUTPUT TERMINALS AND CHECK THE ACTUAL
POWER RATING OF YOUR
EQUIPMENT.  THIS UNIT WILL    “AUTOMATICALLY  RESET  INSTANTLY”

(6)  OVER TEMPERATURE PROTECTION CIRCUITRY IS USED IN PS-9KX TO PREVENT OVER HEAT DAMAGE.
UNIT WILL BE SHUT DOWN  ... 
AFTER 15 MINUTES ( MIN) AT 100% RATED LOAD
AND
  AFTER  25 MINUTES ( MIN ) AT 80% OF RATED LOAD

 

    Have you checked how much current is being drawn from the 5 amp supply? If you are using only 80% of rated amps, this 4 amp power drain can cause a momentary power loss at the 25 minute mark at this level – even sooner, at the end of 15 minutes,  if it supplies its “full rated”  5 amps for 15 minutes.
 
    It will recover automatically, as soon as it cools off, so you will never know if there was a power glitch, except for those trailing star images.
I had it fool me once when the AP-900 seemed to be running just fine. Then it lost power during “one of its MANY slews”,  after more than an hour of (apparently) normal operation. As I was looking for the cause of the system power loss, it came back to life all on its own, and slewed the OTA into the pier before I got to it. So, I assume my scope system (mount and STL) were running at even less than the rated 80% trip level, and it then glitched much later,  at 4 times their warning period. So, even operating at less than 80% power drain is not reliable – just takes longer to fail.
 
    Seems it likes to run at much less than advertised amps – probably just 3.5 amps continuously, where it won’t crow-bar, some time during the night – then come back like nothing had happened. I wonder if the design would have been safer to just shut itself down, in the case of powering motors. That’s why I stopped using my PYRAMID supplies – can’t trust them to not screw things up, dangerously.
 
    I wonder if this” power dip and auto recovery” ...  is what you are experiencing. Check your amps,
and get a larger rated PYRAMID, perhaps the 10 amp would be safer. Even every production unit of the same supply,  can differ, so your presently “better performance” may have a longer trip time, with a faster auto recovery, than the previous PS.
 
Joe


Update to odd tracking/RA behavior

Mike Shade
 

I posted a rather lengthy description of an issue I was having in RA with my system.  Numerous people offered a variety of checks and possible solutions-thanks.

 

What I did last night was:

 

Replace power supply with a newer/different one (13.8V 5A)

Reinstall CP3 control system

Reinstall CP3 power supply cable

Train another PEC curve (which seems better than the one with the CP4, this is subjective though, it looks "smoother")

Change slightly guiding parameters in MaximDL, specifically guide exposure from 10" to 5", aggressiveness is I think 6

 

Shot the same object as over previous nights, NGC 1134.  The results showed the stars as being tighter and rounder at least according to Maxim's ability to measure this.  There were still two instances of "tadpoles" but not as severe as previous imaging runs.  I would not say 100% perfect but there are other issues that may come into play-namely things like seeing and the like (we were in the very low 2" range last night), that could be impacting results.  However, there is a definite improvement over previous nights.

 

So there is a strong suggestion that something that was changed made a difference although it is not definitive.  Now I think work backwards and see if I can add something back in and cause it to suffer a degradation in performance.

 

Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com

 

In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west.  Can it be half

a year since I watched her April rising in the east?  Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights

 

International Dark Sky Association: www.darksky.org

 


Re: Odd tracking/guiding behavior

Mike Shade
 

Yes, all cables go through the mount. The cables are secured but not overly
tightly in other words they can spin freely. I wondered about a cable issue
which is possible. Ordered another guider cable, guider dongle for the
camera, and USB cable. SBIG offered that there was no obvious camera issue
especially since it calibrates just fine in all four directions.



Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com



In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their
lights.

Vega, the brightest one, is now dropping towards the west. Can it be half

a year since I watched her April rising in the east? Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights



International Dark Sky Association: <http://www.darksky.org/>
www.darksky.org



From: ap-gto@... [mailto:ap-gto@...]
Sent: Thursday, October 26, 2017 11:05 AM
To: ap-gto@...
Subject: RE: [ap-gto] Odd tracking/guiding behavior





How are you routing cables from the OTA/camera?



All cables going through the mount?



How about how the cables get to the camera past the rotator?





-Christopher Erickson
Observatory engineer
Summit Kinetics

Waikoloa, HI 96738
<http://www.summitkinetics.com/> www.summitkinetics.com





_____

From: ap-gto@... [mailto:ap-gto@...]
Sent: Thursday, October 26, 2017 4:11 AM
To: ap-gto@...
Subject: [ap-gto] Odd tracking/guiding behavior

Have an issue with RA tracking/guiding.



-1600GTO, have greased RA and DEC, set gear mesh, trained innumerable PEC
curves. CP4 electronics, there have been no software upgrades to the CP4.
The CP4 is an early one, I think around May 2016.

-Planewave CDK 17, Optec Gemini focuser/rotator. Attachment is extension
tubes (solid).

-SBIG STL 6303E, Astro-Don 50mm LRGB filters, unbinned imaging scale
.632"/pixel

-Windows 7 system, Maxim 5.18, Focusmax (older free version), latest V2
driver, ACP 8, Sky6. This is an automated system. Running serial cable to
mount, replaced recently (with AP supplied cable).

-System permanently mounted, polar aligned in observatory. Seeing here runs
2" +/-. Reasonably dark skies.

-Guiding through the guider relays. Recently replaced guider cable and
guider "dongle" on camera. Guider calibrates fine, every time, with a 40
pixel movement. Returns guide star to starting point on calibration.

-Scope balance slightly off in RA and DEC (slightly to load gears).

-Guide exposure is 10", aggressiveness of 7, guider binned 3x3

-I run 10' luminance exposures

-There have been no software upgrades (other than V2), equipment changes,
reconfigurations.

-I have checked for cable drag or snag

-Checked connections, bolts, fasteners and such on OTA and imaging train,
unguided short duration images at 30, 45, and zenith do NOT show any
collimation changes.



What I am seeing on images are intermittent double images or streaked
images. There will be a star and "streaks" where the star moved off and was
moved back (almost like tadpoles if this makes sense). This is ALWAYS in
RA, it is NOT on every image, it is intermittent. I can look at the guider
logs and see BIG jumps in RA for a ruined image. For example the log says
displacement of....32, -.05, .21, 6.35, 2.6, 1.8, .52, -.08 The images show
this displacement with the tadpoles. This is not constant though meaning
that it is not "every 5.3 minutes there is a big jump"...very very
intermittent.



I have seen this before, very rarely in the past and chalked it up
to...whoops...it is now becoming more frequent but not constant. In
addition, many (but not all) images are slightly "off" in RA...maybe a
pixel or two, always in RA, just enough to say "that star is not quite
round". Watching the guiding graph in Maxim shows DEC steady, RA not so
much. Very very rarely I can see a big jump in RA (I have an automated
system so I don't have to watch the system all night).



And yes, I have made sure the PEC curve is on and is not inverted. It is
always in RA. I have checked that there is no wind, clouds. These images
are not at a low elevation. There were two from last night's run that were
streaked, elevation was 55 degrees or so. Images higher up show a slight
out of round in RA...slight.



I know this is pretty vague but...At this point thinking of popping my
original CP3 back on and seeing if this helps...



Any other ideas of checks?



Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com



In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their
lights.

Vega, the brightest one, is now dropping towards the west. Can it be half

a year since I watched her April rising in the east? Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights



International Dark Sky Association: www.darksky.org
<http://www.darksky.org/>







<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_cam
paign=sig-email&utm_content=emailclient> Image removed by sender.

Virus-free.
<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_cam
paign=sig-email&utm_content=emailclient> www.avg.com


Re: Odd tracking/guiding behavior

Mike Shade
 

Thanks, will try and chat on Friday. I did call SBIG and see if there is any camera problem that popped out...there is nothing that came to mind, especially since the guider calibrates just fine. Am replacing yet again the guider cable, guider dongle and USB cable with new stuff from SBIG. Unlikely that this are the problems but it is fairly cheap to try.



Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com



In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west. Can it be half

a year since I watched her April rising in the east? Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights



International Dark Sky Association: <http://www.darksky.org/> www.darksky.org



From: ap-gto@... [mailto:ap-gto@...]
Sent: Thursday, October 26, 2017 9:56 AM
To: ap-gto@...
Subject: Re: [ap-gto] Odd tracking/guiding behavior





Sounds mechanical, not electronic. We can check out the RA axis, but you would need to talk directly with Howard or George about your situation, and they may want you to do some simple tests.

Rolando







-----Original Message-----
From: 'Mike Shade' mshade@q.com [ap-gto] <ap-gto@...>
To: ap-gto <ap-gto@...>
Sent: Thu, Oct 26, 2017 9:16 am
Subject: [ap-gto] Odd tracking/guiding behavior



Have an issue with RA tracking/guiding.



-1600GTO, have greased RA and DEC, set gear mesh, trained innumerable PEC curves. CP4 electronics, there have been no software upgrades to the CP4. The CP4 is an early one, I think around May 2016.

-Planewave CDK 17, Optec Gemini focuser/rotator. Attachment is extension tubes (solid).

-SBIG STL 6303E, Astro-Don 50mm LRGB filters, unbinned imaging scale .632"/pixel

-Windows 7 system, Maxim 5.18, Focusmax (older free version), latest V2 driver, ACP 8, Sky6. This is an automated system. Running serial cable to mount, replaced recently (with AP supplied cable).

-System permanently mounted, polar aligned in observatory. Seeing here runs 2" +/-. Reasonably dark skies.

-Guiding through the guider relays. Recently replaced guider cable and guider "dongle" on camera. Guider calibrates fine, every time, with a 40 pixel movement. Returns guide star to starting point on calibration.

-Scope balance slightly off in RA and DEC (slightly to load gears).

-Guide exposure is 10", aggressiveness of 7, guider binned 3x3

-I run 10' luminance exposures

-There have been no software upgrades (other than V2), equipment changes, reconfigurations.

-I have checked for cable drag or snag

-Checked connections, bolts, fasteners and such on OTA and imaging train, unguided short duration images at 30, 45, and zenith do NOT show any collimation changes.



What I am seeing on images are intermittent double images or streaked images. There will be a star and "streaks" where the star moved off and was moved back (almost like tadpoles if this makes sense). This is ALWAYS in RA, it is NOT on every image, it is intermittent. I can look at the guider logs and see BIG jumps in RA for a ruined image. For example the log says displacement of....32, -.05, .21, 6.35, 2.6, 1.8, .52, -.08 The images show this displacement with the tadpoles. This is not constant though meaning that it is not "every 5.3 minutes there is a big jump"...very very intermittent.



I have seen this before, very rarely in the past and chalked it up to...whoops...it is now becoming more frequent but not constant. In addition, many (but not all) images are slightly "off" in RA...maybe a pixel or two, always in RA, just enough to say "that star is not quite round". Watching the guiding graph in Maxim shows DEC steady, RA not so much. Very very rarely I can see a big jump in RA (I have an automated system so I don't have to watch the system all night).



And yes, I have made sure the PEC curve is on and is not inverted. It is always in RA. I have checked that there is no wind, clouds. These images are not at a low elevation. There were two from last night's run that were streaked, elevation was 55 degrees or so. Images higher up show a slight out of round in RA...slight.



I know this is pretty vague but...At this point thinking of popping my original CP3 back on and seeing if this helps...



Any other ideas of checks?



Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com



In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west. Can it be half

a year since I watched her April rising in the east? Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights



International Dark Sky Association: www.darksky.org <http://www.darksky.org/>









[Non-text portions of this message have been removed]


Re: Problem with APPM

Ray Gralak
 

Dan,

The firmware cannot possibly have anything to do with that issue. Something is probably misconfigured in TheSkyX or the way you are running APPM (i.e. not running all apps "as administrator", or "normal").

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro: http://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver
Author of PulseGuide: http://www.pulseguide.com
Author of Sigma: http://www.gralak.com/sigma

-----Original Message-----
From: ap-gto@... [mailto:ap-gto@...]
Sent: Thursday, October 26, 2017 5:35 PM
To: ap-gto@...
Subject: [ap-gto] Problem with APPM



Having a problem mapping.

I recently updated my AP1600 CP4 firmware to Vcp4-01-10 and updated APCC to version 1.6.0.3

Prior to updating, I was able to map with APPM without issue. Now, I can use APPM to plate solve and
recalibrate (including allsky) with each plate solve being successful however; when I try to make a run, every
single point fails. I can stop a run and restart with the same results. If I try to plate solve again, I receive the
error "Failed to Initialize: Invalid Plate Solver". APPM must be restarted for plate solve to function properly
again.

Hoping someone can help me out with this.

Thanks,

Dan Ford



Re: Problem with APPM

 

Should have mentioned that I'm using the V2 driver version 5.10.02 and the SkyX for plate solving.
Dan Ford


Problem with APPM

 

Having a problem mapping.

I recently updated my AP1600 CP4 firmware to Vcp4-01-10 and updated APCC to version 1.6.0.3

Prior to updating, I was able to map with APPM without issue. Now, I can use APPM to plate solve and recalibrate (including allsky) with each plate solve being successful however; when I try to make a run, every single point fails. I can stop a run and restart with the same results. If I try to plate solve again, I receive the error "Failed to Initialize: Invalid Plate Solver". APPM must be restarted for plate solve to function properly again.

Hoping someone can help me out with this.

Thanks,

Dan Ford


Re: Rain and the CP4

Steve Reilly
 

Christopher,

 

You’re right of course about the best design being one where the roof can close with any telescope position and I’ll have to revisit the design I used and look at fabricating some higher clearance roof trusses. With that in place you can use a hard wire direct close device that activates on any moisture reading from the cloud sensor if the roof fails to close when conditions get cloudy. And as you said, all systems are subject to fail at some point in time. In my case it took 15 years but none the less damaging. I even have a circuit from my whole hose generator powering the observatory in the case of power failure, all long as there is LP in the tank. But the motor could fail, the AC motor controller could fail, anything in the system that drives the roof could fail so there is not fail safe, at least not one most of us could afford. I did HVAC work and the local telephone company was one of my biggest customers. We did their switch gear rooms and designed for redundancy but again, it can only go so far. The FCC has fines that accumulate quickly depending on how long a switch is down so there was a definite monetary incentive to do the best you could. When I took over as their mechanical supervisor for their systems in the state of Virginia I did a quick survey and was amazed that although they had redundant cooling towers, chillers, generators, and so on they only had one set of chiller lines. No independent cooling lines in case of a major break or stuck valves although they did have a great series of bypass valves to reroute but nothing taken into account of line breakage. Within months we had contract for a set of parallel cooling lines. Still subject to more combinations of failures than most could think of but we had the major systems covered, remote alarms installed, and  portable backup systems if needed. But…..

 

-Steve

 

 

 

From: ap-gto@... [mailto:ap-gto@...]
Sent: Tuesday, October 24, 2017 8:33 PM
To: ap-gto@...
Subject: RE: [ap-gto] Rain and the CP4

 

 

I try to describe reliability to people as a scale, not a binary state.

 

Everything you can do to improve reliability through creating failsafes, fail-overs, backup systems, minimizing SPoF's and minimizing potential cascade failures, the better.

 

And the real saying is "given enough time, any system WILL fail."

 

Adding a telescoping pier to work in parallel with a mount park command (and not serially) means that as long as at least one of them functions as designed, the scope and observatory would be safe.  And hopefully there is sufficient telemetry being collected and parsed, that if one of the two functions were to fail, the system would automatically notify someone.

 

The safest thing is to have an observatory that can close regardless of the scope position.  Any other approach significantly increases the risk to the scope and other observatory equipment.  And this is certainly possible with a horizon-to-horizon view and not just a 20 degree view.  And you won't even need a telescoping pier.

 

https://photos.app.goo.gl/ZarT9kLv0U9QTZxr1

 

https://photos.app.goo.gl/gYII4CtlD2r0xxLf2

 

 

-Christopher Erickson
Observatory engineer
Summit Kinetics

Waikoloa, HI 96738
www.summitkinetics.com

 

 


From: ap-gto@... [mailto:ap-gto@...]
Sent: Tuesday, October 24, 2017 11:16 AM
To: ap-gto@...
Subject: RE: [ap-gto] Rain and the CP4

Christopher,

 

Any system can fail. However, there are safeguards that can make that less likely to happen. For instance, it would appear in Steve's case ACP needed confirmation that the scope was parked, and couldn't get confirmation because it relied on the mount driver or ASCOM to make that determination.  Adding a third condition (pier position) wouldn't have made a difference if ACP was the one that needed to issue that command.

 

My system relies only on a mechanical IR relay, combined to a weather sensor on the controller. Any loss of the serial connection to the scope wouldn't matter. If the scope parked, and the controller senses wind, rain, or clouds for a set amount of time, the roof will close. I don't use ACP, but rather CCDA5. CCDAP5 also may have failed (or, more likely crashed) with a loss to the connection to the mount, but my system would have still closed the roof if the OTA was parked. So if the scenario was ACP gave the park command, the scope parked, and then the serial connection failed, causing ACP to not issue the close command, that failure would not have prevented the roof from closing on my observatory, because once the OTA parked, the controller itself, not ACP would have automatically closed the roof if weather conditions are met.

 

Now if the scope isn't parked, that's a whole different ball game. In that case, the roof shouldn't close. If mounts had a hard wired park switch, we wouldn't need to rely ACP or CCDAP5 to command the park position at all. The controller could do that, too.

 

On the Pier Tech side, if there is a way to add a hard wire sensor and relay to lower the pier, and close the roof, that would work pretty well if you were willing to accept the issues related to a moving pier and cost for as a solution. I am not.

 

I do agree, however, the second most safe method is a sensor that closes the roof when it senses clouds or rain irregardless of the position of the scope, and that does not rely on the PC, ASCOM, or mount controller for that determination.  However, that isn't always possible (it's really hard to do with an 8'x8' observatory unless you want a FOV of about 20 degrees straight up).

 

The safest thing, however, is to keep track of the weather, and not open the roof when there is a good chance it will rain, and to actively monitor conditions it if the weather is likely to take a turn for the worse. There's nothing safer than using common sense. Imaging when there is a good chance for rain simply isn't a good idea no matter what type of roof you have.

 

GM



---In ap-gto@..., <christopher.k.erickson@...> wrote :

FWIW every time I have been asked about the benefits versus liabilities of remote or robotic observatories that can only be operated when the mount is in a specific position, I respond that it is only a matter of time before the scope and equipment get drenched by weather.  Basically, it WILL happen at some point.  It isn't a design I recommend.

 

Much better to design an observatory that can be closed or opened regardless of the mount position.

 

For those who already have an observatory that requires the scope to be in a certain park position before the roof can be operated, there is hope.  Install a Pier Tech telescoping pier or build you own using one, two or three Linak vertical columns from eBay.  When you want to close the roof, park the mount AND run the pier down.  If implemented properly it will only require one of the two commands to function properly to protect the scope and observatory and allow the roof/shutter to operate safely.

 

But it is worth saying again.  Having a remote or robotic observatory that can only be opened or closed when the scope is in a specific position is a BAD idea.

 

 

-Christopher Erickson
Observatory engineer
Summit Kinetics

Waikoloa, HI 96738
www.summitkinetics.com

 

Virus-free. www.avg.com


Re: Odd tracking/guiding behavior

Christopher Erickson
 

How are you routing cables from the OTA/camera?
 
All cables going through the mount?
 
How about how the cables get to the camera past the rotator?
 
 
-Christopher Erickson
Observatory engineer
Summit Kinetics
Waikoloa, HI 96738
www.summitkinetics.com
 



From: ap-gto@... [mailto:ap-gto@...]
Sent: Thursday, October 26, 2017 4:11 AM
To: ap-gto@...
Subject: [ap-gto] Odd tracking/guiding behavior

Have an issue with RA tracking/guiding. 

 

-1600GTO, have greased RA and DEC, set gear mesh, trained innumerable PEC curves.  CP4 electronics, there have been no software upgrades to the CP4.  The CP4 is an early one, I think around May 2016. 

-Planewave CDK 17, Optec Gemini focuser/rotator.  Attachment is extension tubes (solid).

-SBIG STL 6303E, Astro-Don 50mm LRGB filters, unbinned imaging scale .632"/pixel

-Windows 7 system, Maxim 5.18, Focusmax (older free version), latest V2 driver, ACP 8, Sky6.  This is an automated system.  Running serial cable to mount, replaced recently (with AP supplied cable).

-System permanently mounted, polar aligned in observatory.  Seeing here runs 2" +/-.  Reasonably dark skies.

-Guiding through the guider relays.  Recently replaced guider cable and guider "dongle" on camera.  Guider calibrates fine, every time, with a 40 pixel movement.  Returns guide star to starting point on calibration.

-Scope balance slightly off in RA and DEC (slightly to load gears).

-Guide exposure is 10", aggressiveness of 7, guider binned 3x3

-I run 10' luminance exposures

-There have been no software upgrades (other than V2), equipment changes, reconfigurations.

-I have checked for cable drag or snag

-Checked connections, bolts, fasteners and such on OTA and imaging train, unguided short duration images at 30, 45, and zenith do NOT show any collimation changes.

 

What I am seeing on images are intermittent double images or streaked images.  There will be a star and "streaks" where the star moved off and was moved back (almost like tadpoles if this makes sense).  This is ALWAYS in RA, it is NOT on every image, it is intermittent.  I can look at the guider logs and see BIG jumps in RA for a ruined image.  For example the log says displacement of....32, -.05, .21, 6.35, 2.6, 1.8, .52, -.08  The images show this displacement with the tadpoles.  This is not constant though meaning that it is not "every 5.3 minutes there is a big jump"...very very intermittent.

 

I have seen this before, very rarely in the past and chalked it up to...whoops...it is now becoming more frequent but not constant.  In addition, many (but not all)  images are slightly "off" in RA...maybe a pixel or two, always in RA, just enough to say "that star is not quite round".  Watching the guiding graph in Maxim shows DEC steady, RA not so much.  Very very rarely I can see a big jump in RA (I have an automated system so I don't have to watch the system all night). 

 

And yes, I have made sure the PEC curve is on and is not inverted.  It is always in RA.  I have checked that there is no wind, clouds.  These images are not at a low elevation.  There were two from last night's run that were streaked, elevation was 55 degrees or so.  Images higher up show a slight out of round in RA...slight.

 

I know this is pretty vague but...At this point thinking of popping my original CP3 back on and seeing if this helps...

 

Any other ideas of checks?

 

Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com

 

In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west.  Can it be half

a year since I watched her April rising in the east?  Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights

 

International Dark Sky Association: www.darksky.org

 


Virus-free. www.avg.com


Re: Odd tracking/guiding behavior

Roland Christen
 

Sounds mechanical, not electronic. We can check out the RA axis, but you would need to talk directly with Howard or George about your situation, and they may want you to do some simple tests.

Rolando



-----Original Message-----
From: 'Mike Shade' mshade@q.com [ap-gto]
To: ap-gto
Sent: Thu, Oct 26, 2017 9:16 am
Subject: [ap-gto] Odd tracking/guiding behavior



Have an issue with RA tracking/guiding. 
 
-1600GTO, have greased RA and DEC, set gear mesh, trained innumerable PEC curves.  CP4 electronics, there have been no software upgrades to the CP4.  The CP4 is an early one, I think around May 2016. 
-Planewave CDK 17, Optec Gemini focuser/rotator.  Attachment is extension tubes (solid).
-SBIG STL 6303E, Astro-Don 50mm LRGB filters, unbinned imaging scale .632"/pixel
-Windows 7 system, Maxim 5.18, Focusmax (older free version), latest V2 driver, ACP 8, Sky6.  This is an automated system.  Running serial cable to mount, replaced recently (with AP supplied cable).
-System permanently mounted, polar aligned in observatory.  Seeing here runs 2" +/-.  Reasonably dark skies.
-Guiding through the guider relays.  Recently replaced guider cable and guider "dongle" on camera.  Guider calibrates fine, every time, with a 40 pixel movement.  Returns guide star to starting point on calibration.
-Scope balance slightly off in RA and DEC (slightly to load gears).
-Guide exposure is 10", aggressiveness of 7, guider binned 3x3
-I run 10' luminance exposures
-There have been no software upgrades (other than V2), equipment changes, reconfigurations.
-I have checked for cable drag or snag
-Checked connections, bolts, fasteners and such on OTA and imaging train, unguided short duration images at 30, 45, and zenith do NOT show any collimation changes.
 
What I am seeing on images are intermittent double images or streaked images.  There will be a star and "streaks" where the star moved off and was moved back (almost like tadpoles if this makes sense).  This is ALWAYS in RA, it is NOT on every image, it is intermittent.  I can look at the guider logs and see BIG jumps in RA for a ruined image.  For example the log says displacement of....32, -.05, .21, 6.35, 2.6, 1.8, .52, -.08  The images show this displacement with the tadpoles.  This is not constant though meaning that it is not "every 5.3 minutes there is a big jump"...very very intermittent.
 
I have seen this before, very rarely in the past and chalked it up to...whoops...it is now becoming more frequent but not constant.  In addition, many (but not all)  images are slightly "off" in RA...maybe a pixel or two, always in RA, just enough to say "that star is not quite round".  Watching the guiding graph in Maxim shows DEC steady, RA not so much.  Very very rarely I can see a big jump in RA (I have an automated system so I don't have to watch the system all night). 
 
And yes, I have made sure the PEC curve is on and is not inverted.  It is always in RA.  I have checked that there is no wind, clouds.  These images are not at a low elevation.  There were two from last night's run that were streaked, elevation was 55 degrees or so.  Images higher up show a slight out of round in RA...slight.
 
I know this is pretty vague but...At this point thinking of popping my original CP3 back on and seeing if this helps...
 
Any other ideas of checks?
 
Mike J. Shade: mshade@q.com
Mike J. Shade Photography:
 
In War: Resolution
In Defeat: Defiance
In Victory: Magnanimity
In Peace: Goodwill
Sir Winston Churchill
Already, in the gathering dusk, a few of the stars are turning on their lights.
Vega, the brightest one, is now dropping towards the west.  Can it be half
a year since I watched her April rising in the east?  Low in the southwest
Antares blinks a sad farwell to fall...
Leslie Peltier, Starlight Nights
 
International Dark Sky Association: www.darksky.org
 



Re: Odd tracking/guiding behavior

Joe Zeglinski
 

Mike,
 
   Is there an OPTEC log which might indicate very minor rotator compensation, (due to the STL series cameras (chin) balance offset), trying to stay on-angle?
Do some runs with rotator powered off. Rotator servo response could be elevation angle dependent, probably worse toward zenith – perhaps try a lower target.
 
Joe


Odd tracking/guiding behavior

Mike Shade
 

Have an issue with RA tracking/guiding. 

 

-1600GTO, have greased RA and DEC, set gear mesh, trained innumerable PEC curves.  CP4 electronics, there have been no software upgrades to the CP4.  The CP4 is an early one, I think around May 2016. 

-Planewave CDK 17, Optec Gemini focuser/rotator.  Attachment is extension tubes (solid).

-SBIG STL 6303E, Astro-Don 50mm LRGB filters, unbinned imaging scale .632"/pixel

-Windows 7 system, Maxim 5.18, Focusmax (older free version), latest V2 driver, ACP 8, Sky6.  This is an automated system.  Running serial cable to mount, replaced recently (with AP supplied cable).

-System permanently mounted, polar aligned in observatory.  Seeing here runs 2" +/-.  Reasonably dark skies.

-Guiding through the guider relays.  Recently replaced guider cable and guider "dongle" on camera.  Guider calibrates fine, every time, with a 40 pixel movement.  Returns guide star to starting point on calibration.

-Scope balance slightly off in RA and DEC (slightly to load gears).

-Guide exposure is 10", aggressiveness of 7, guider binned 3x3

-I run 10' luminance exposures

-There have been no software upgrades (other than V2), equipment changes, reconfigurations.

-I have checked for cable drag or snag

-Checked connections, bolts, fasteners and such on OTA and imaging train, unguided short duration images at 30, 45, and zenith do NOT show any collimation changes.

 

What I am seeing on images are intermittent double images or streaked images.  There will be a star and "streaks" where the star moved off and was moved back (almost like tadpoles if this makes sense).  This is ALWAYS in RA, it is NOT on every image, it is intermittent.  I can look at the guider logs and see BIG jumps in RA for a ruined image.  For example the log says displacement of....32, -.05, .21, 6.35, 2.6, 1.8, .52, -.08  The images show this displacement with the tadpoles.  This is not constant though meaning that it is not "every 5.3 minutes there is a big jump"...very very intermittent.

 

I have seen this before, very rarely in the past and chalked it up to...whoops...it is now becoming more frequent but not constant.  In addition, many (but not all)  images are slightly "off" in RA...maybe a pixel or two, always in RA, just enough to say "that star is not quite round".  Watching the guiding graph in Maxim shows DEC steady, RA not so much.  Very very rarely I can see a big jump in RA (I have an automated system so I don't have to watch the system all night). 

 

And yes, I have made sure the PEC curve is on and is not inverted.  It is always in RA.  I have checked that there is no wind, clouds.  These images are not at a low elevation.  There were two from last night's run that were streaked, elevation was 55 degrees or so.  Images higher up show a slight out of round in RA...slight.

 

I know this is pretty vague but...At this point thinking of popping my original CP3 back on and seeing if this helps...

 

Any other ideas of checks?

 

Mike J. Shade: mshade@q.com

Mike J. Shade Photography:

mshadephotography.com

 

In War: Resolution

In Defeat: Defiance

In Victory: Magnanimity

In Peace: Goodwill

Sir Winston Churchill

Already, in the gathering dusk, a few of the stars are turning on their lights.

Vega, the brightest one, is now dropping towards the west.  Can it be half

a year since I watched her April rising in the east?  Low in the southwest

Antares blinks a sad farwell to fall...

Leslie Peltier, Starlight Nights

 

International Dark Sky Association: www.darksky.org

 


Re: Dual OTA's and pointing...

C. G. Anderson
 

I had thought about something like this, but Howard seems to have negated it. However, but my OTA alone weights over thirty pounds, so would likely tax any such device...  Chris


Re: Dual OTA's and pointing...

C. G. Anderson
 

Howard, thanks!  I will do this. Chris