Date   

AP 1200 - R.A. motor/gearbox housing

werner.pribil
 

Hello,

My new AP 1200 is mounted on a permanent pier and the R.A. motor
housing is at the same altitude as my forehead when I stand next to
my mount. Yesterday I checked the pier adapter knobs and I turned my
head down to inspect the left knob. At this moment I kocked with my
forehead against the R.A. motor housing.
Now I have three questions:

- Can this (little) bump disguise the accurate R.A. worm and wheel
adjustments ?

- Do you know an example that shows how strong a strike must be to
affect the gear alignment ? In the manual (p26) I can read that I
should not transport my AP 1200 on a flat surface (on the ground or
trunk of my car). But this information gives me no idea, how rugged
(or sensitive) the motor/gearbox housing is in fact !

- After the strike I checked the STATUS (p.49) in the Tools menu
(keypad v4.12) and the result was "All Systems Go" .
Is this information enough to say that the strike did not affect the
worm and wheel adustments ?


Thank you for your answer !

Werner


Re: An easier Pasillx N & S Polar Alignment method

Joe Zeglinski
 

Bien sur, Roland, et merci.
That's what I eventually figured you were doing.

Joe

----- Original Message -----
From: <chris1011@...>
To: <ap-gto@...>
Sent: Sunday, September 21, 2008 2:45 PM
Subject: Re: [ap-gto] Re: An easier Pasillx N & S Polar Alignment method





I would have started by aligning the finder to the OTA using an
"illuminated cross hair eyepiece", until these two were parallel, and then
go through your procedure to make the OTA/finder orthogonal with the mount,
and then also polar aligned.


It would have taken me all night to get the tube assembly perfectly orthogonal. I din't care to do that. My main mission was to get the mount POLAR ALIGNED. For that, having a scope with orthogonal crosshairs makes the job very easy. That scope was the finder. You may not understand this, but the mount is always orthogonal. It is the main scope that can be off for various reasons. In the case of an SCT for instance, just collimating the secondary mirror throws off the scope orthogonality. Therefore, it is not always possible to get the main scope to always be dead nuts on. I don't need it to be dead nuts on. I did not need it to do my polar alignment. I just needed a scope, any scope, to be orthogonal to the mount. The finder was the perfect choice because it is soooo easy to adjust the orthogonality.

For finding things later on with the main scope, it does not need to be perfectly on. It's close enough that all object always appear somewhere in the CCD field. Comprende vous?

Rolando

-----Original Message-----
From: Joseph Zeglinski <J.Zeglinski@...>
To: ap-gto@...
Sent: Sat, 20 Sep 2008 1:02 pm
Subject: [ap-gto] Re: An easier Pasillx N & S Polar Alignment method



Hi Rolando,

I too was a bit confused, but let that slip. Now I am really confused.
I understand your method and the explanation is clear, but I don't get the
"initial conditions".

Was the main OTA (with finder on top), already perfectly orthogonal to
the mount, or is the finder physically attached to the AP-3200 mount, and
therefore requires its own alignment? Even with the latter, adjusting the
mount Alt-Az knobs for the finder, ruins the OTA derived mount alignment.
Saying:
*
******
The advantage of using the 8x50 finder was that i could quickly adjust it
via
the thumbscrews to be perfectly orthogonal to the mount (unlike the Big Mak
which was off about 15 arc minutes).
******

... implies that this was an "initial installation", and the finder and OTA
were not yet aligned to each other.
I would have started by aligning the finder to the OTA using an
"illuminated cross hair eyepiece", until these two were parallel, and then
go through your procedure to make the OTA/finder orthogonal with the mount,
and then also polar aligned.

The way I read this, you are making the (OTA attached) finder orthogonal
to the mount, and once completed, you then need to repeat for the main OTA -
which now misaligns the finder.

The only way this explanation would seem right to me - is if you had
said that the OTA was already previously orthogonal to the mount, and the
procedure was merely to do the same for the finder.
But that is a harder way to do that than using a cross hair eyepiece in the
first place. The only saving is the purchase of that special eyepiece, which
I assume most of us already own.

Thanks for a further clarification.
Joe

----- Original Message -----
From: <chris1011@...>
To: <ap-gto@...>
Sent: Saturday, September 20, 2008 11:54 AM
Subject: Re: [ap-gto] Re: An easier Pasillx N & S Polar Alignment method


The mount's altitude axis
is properly set and the finderscope's adjuster screws are also properly
set, so
you are 1/2 polar aligned and the fin
der is perfectly orthogonal.

Rolando



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Re: An easier Pasillx N & S Polar Alignment method- NOW New Gear Cutting Procedu

Roland Christen
 

Hmmmm, this old fart wonders if you will use the new Gear Cutting
Method on the AP1200s just now entering production?

We always apply new techniques to our products. They evolve, along with our scopes.

Rolando

-----Original Message-----
From: tucstargzr <tucstargzr@...>
To: ap-gto@...
Sent: Sat, 20 Sep 2008 11:40 am
Subject: [ap-gto] Re: An easier Pasillx N & S Polar Alignment method- NOW New Gear Cutting Procedu



--- In ap-gto@..., chris1011@... wrote:

In a message dated 9/19/2008 5:41:18 AM Central Daylight Time,
docsquic@... writes:
SNIP
The production worm on this 3600 mount is made with a new gear
cutting method that we developed here after much testing, and it
produced a raw periodic error of under 2 arc seconds without PEM in a
5 minute worm cycle.
<<<<snip

Rolando

Hmmmm, this old fart wonders if you will use the new Gear Cutting
Method on the AP1200s just now entering production?

Tom
Ye Olde Fart from Tucson, AZ


------------------------------------

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see http://groups.yahoo.com/group/ap-gtoYahoo! Groups Links


Re: An easier Pasillx N & S Polar Alignment method

Roland Christen
 

I would have started by aligning the finder to the OTA using an
"illuminated cross hair eyepiece", until these two were parallel, and then
go through your procedure to make the OTA/finder orthogonal with the mount,
and then also polar aligned.


It would have taken me all night to get the tube assembly perfectly orthogonal. I din't care to do that. My main mission was to get the mount POLAR ALIGNED. For that, having a scope with orthogonal crosshairs makes the job very easy. That scope was the finder. You may not understand this, but the mount is always orthogonal. It is the main scope that can be off for various reasons. In the case of an SCT for instance, just collimating the secondary mirror throws off the scope orthogonality. Therefore, it is not always possible to get the main scope to always be dead nuts on. I don't need it to be dead nuts on. I did not need it to do my polar alignment. I just needed a scope, any scope, to be orthogonal to the mount. The finder was the perfect choice because it is soooo easy to adjust the orthogonality.

For finding things later on with the main scope, it does not need to be perfectly on. It's close enough that all object always appear somewhere in the CCD field. Comprende vous?

Rolando

-----Original Message-----
From: Joseph Zeglinski <J.Zeglinski@...>
To: ap-gto@...
Sent: Sat, 20 Sep 2008 1:02 pm
Subject: [ap-gto] Re: An easier Pasillx N & S Polar Alignment method



Hi Rolando,

I too was a bit confused, but let that slip. Now I am really confused.
I understand your method and the explanation is clear, but I don't get the
"initial conditions".

Was the main OTA (with finder on top), already perfectly orthogonal to
the mount, or is the finder physically attached to the AP-3200 mount, and
therefore requires its own alignment? Even with the latter, adjusting the
mount Alt-Az knobs for the finder, ruins the OTA derived mount alignment.
Saying:
*
******
The advantage of using the 8x50 finder was that i could quickly adjust it
via
the thumbscrews to be perfectly orthogonal to the mount (unlike the Big Mak
which was off about 15 arc minutes).
******

... implies that this was an "initial installation", and the finder and OTA
were not yet aligned to each other.
I would have started by aligning the finder to the OTA using an
"illuminated cross hair eyepiece", until these two were parallel, and then
go through your procedure to make the OTA/finder orthogonal with the mount,
and then also polar aligned.

The way I read this, you are making the (OTA attached) finder orthogonal
to the mount, and once completed, you then need to repeat for the main OTA -
which now misaligns the finder.

The only way this explanation would seem right to me - is if you had
said that the OTA was already previously orthogonal to the mount, and the
procedure was merely to do the same for the finder.
But that is a harder way to do that than using a cross hair eyepiece in the
first place. The only saving is the purchase of that special eyepiece, which
I assume most of us already own.

Thanks for a further clarification.
Joe

----- Original Message -----
From: <chris1011@...>
To: <ap-gto@...>
Sent: Saturday, September 20, 2008 11:54 AM
Subject: Re: [ap-gto] Re: An easier Pasillx N & S Polar Alignment method


The mount's altitude axis
is properly set and the finderscope's adjuster screws are also properly
set, so
you are 1/2 polar aligned and the fin
der is perfectly orthogonal.

Rolando



------------------------------------

To UNSUBSCRIBE, or for general information on the ap-gto list
see http://groups.yahoo.com/group/ap-gtoYahoo! Groups Links


Re: An easier Pasillx N & S Polar Alignment method

Chuck Hancock
 

Hey Joe,
just like adding shims to the OTA for the same reason. So, if I can't get the mount aligned after a few tries, work on shimming (adjusting set screws) of the finder, and recursively - finally - get the (mount + finder)
All you have to do is get the finder scope orthogonal at the very first. You don't need to waste time with a few tries prior to that. I believe Roland covers this in one of his more recent posts.

Of course, the end result is perfect GOTO for the finder, while the OTA field - and thus the camera view are left permanently "off the mark a bit". I can now see why Roland used that procedure, since he might have only been interested in quickly field testing a mount prior to shipment, but that is not something I would desire as a regular "field set up". Although, if the OTA is not that far off, it might be tolerable - just
Actually, after you polar align, you merely recalibrate using the recal function of the hand controller, and your OTA will be RIGHT on the mark. Until your mount flips sides. Then you just recal again on any object in the database. Quick field test or all night imaging, this method works for polar aligning the mount.
SLIGHTLY OFF TOPIC:
By the way, I find adjusting finders in "double ring mounts" a real ain - 6 screws, and possible dents or scratches on the finder tube!

I found a much better method for the tiny 7x finder on my OTA. I removed the front set of 3 screws from the front ring mount, and put a suitably thick O-Ring on the finder front end, so that the finder fit snugly inside
....................clip........................
sliced rubber pipe insulation formed into a donut, instead. Now you only need to futz with the rear mount ring screws to get the OTA orthogonal.
Wish somebody would make this a product. Sure beats adding brass shims to the OTA mount rings!
I think that would speed things up if Roland wanted to always have OTA's quickly orthogonal, and tolerate the finder being slightly off centre - which can be squared up with the OTA much easier, upon completion.
Probably not a very common issue for the OTA, but finders on OTA's get bumped and misaligned after almost every trip.

There's probably no reason to go to that much trouble. The method you describe for your finder scope works OK, I'm sure. However, leaving all the screws in place does the same thing. You just need to choose whether you want to adjust the front set, the rear set, or both. Shimming the scope is another story. I haven't tried it, but having an orthogonal finder scope makes this unnecessary. Still, I may try it sometime just for the satisfaction. At least it would be a "set it and forget it" procedure, given the precision and rigidity of the AP mounting rings. As for your proposed invention, adding resilient (or, indeed, inflatable) components to the mounting system may introduce an unreasonable amount of inaccuracy, especially when you change the scope's angular orientation with respect to the force of gravity. You would then need modeling software, for sure, to compensate! ;)

As for the finder scope staying aligned, I have found over the past few sessions that the finder maintains an excellent degree of alignment every time I remount it on the scope's female dovetail bracket. I do tend to mount the 130EDF the same way in the rings every time, with the finder bracket lined up with the flat top of the mounting rings, so maybe this has something to do with my consistent results between the mount and the finder scope.

Best regards,
Chuck


Re: An easier Pasillx N & S Polar Alignment method

Joe Zeglinski
 

Of course - NOW I see it - thanks Chuck.

In essence, adjusting the "finder set screws" to make it orthogonal, is just like adding shims to the OTA for the same reason. So, if I can't get the mount aligned after a few tries, work on shimming (adjusting set screws) of the finder, and recursively - finally - get the (mount + finder) perfectly orthogonal and all aligned on the pole, tolerating the OTA being left off-centre, in the process.

I see now, that is a lot easier than futzing with brass shims with the (Mount + OTA) alternative.
Of course, the end result is perfect GOTO for the finder, while the OTA field - and thus the camera view are left permanently "off the mark a bit". I can now see why Roland used that procedure, since he might have only been interested in quickly field testing a mount prior to shipment, but that is not something I would desire as a regular "field set up". Although, if the OTA is not that far off, it might be tolerable - just.

SLIGHTLY OFF TOPIC:
By the way, I find adjusting finders in "double ring mounts" a real ain - 6 screws, and possible dents or scratches on the finder tube!

I found a much better method for the tiny 7x finder on my OTA. I removed the front set of 3 screws from the front ring mount, and put a suitably thick O-Ring on the finder front end, so that the finder fit snugly inside the ring mount. This O-Ring then acts like a "pivot bearing" - like on a large machine gun bipod (e.g. Brenn Gun of old) - so all I need to do is adjust the one set of screws at the rear ring mount, which causes the finder to swivel around on the front O-Ring. I get a lot more precise adjustment, quickly and smoothly.

That could be done with similar large OTA ring mounts. You would need to buy something like two huge O-Rings (like those used on "needle work stretch frames" from hobby or sewing centres), spaced an inch apart near the OTA dew shield/corrector, and then a small air inflatable tire tube in the front ring. Fill it with air using a bicycle pump so it grips the OTA in the one inch channel, between the needle work frame O-Rings.
You could probably devise a similar "filler" with rigid foam rubber, or sliced rubber pipe insulation formed into a donut, instead. Now you only need to futz with the rear mount ring screws to get the OTA orthogonal.
Wish somebody would make this a product. Sure beats adding brass shims to the OTA mount rings!
I think that would speed things up if Roland wanted to always have OTA's quickly orthogonal, and tolerate the finder being slightly off centre - which can be squared up with the OTA much easier, upon completion.
Probably not a very common issue for the OTA, but finders on OTA's get bumped and misaligned after almost every trip.

Joe

----- Original Message -----
From: "Chuck Hancock" <cdh59@...>
To: <ap-gto@...>
Sent: Sunday, September 21, 2008 10:47 AM
Subject: Re: [ap-gto] Re: An easier Pasillx N & S Polar Alignment method


Hey Joe,
The concept you should know here is that the OTA doesn't need to be
orthogonal. You only need the finder scope orthogonal to the mount (not
the OTA) in order to polar align the mount's RA axis.


Re: An easier Pasillx N & S Polar Alignment method

Chuck Hancock
 

Hey Joe,
The concept you should know here is that the OTA doesn't need to be orthogonal. You only need the finder scope orthogonal to the mount (not the OTA) in order to polar align the mount's RA axis.

Suppose for a moment that your scope OTA, finder scope, and mount are all three orthogonal and all three perfectly polar aligned. So your tracking is "dead nuts". Add to that a camera that you want to photograph any object in the sky. You can mount the camera to the scope, piggyback on the mounting rings and point it in ANY direction in the sky. As long as the scope is tracking, the camera will track as well, as it too is rotating about the pole (and the RA axis). It points at an independent target, but still benefits from the tracking of the scope. The fact that it is on a different target makes no difference at all. Try setting up your mount and do it yourself to prove it. It really helps to see it on the mount, even if you just set up indoors.

Go back now to the situation that was described in the procedure to kick off this branch of the discussion ("Howard and myself..."). The finder scope helps gets the mount aligned. The OTA is a little off. No big deal. Go to the target object, center the object, then do a realign (or not). Start your camera exposure, and the mount and OTA will track just right even thought the finder is not pointing at exactly the same spot as the scope. The only time the orthogonality of the OTA will make a difference here is when your mount flips to the other side of the sky, that is, when you goto a different object. Then the pointing will be off by twice the orthogonality error. In the case of the OTA, just a half a degree (2x 15 arc minutes). In the case of our imaginary piggyback camera, who knows where!

Best regards,
Chuck Hancock

Joseph Zeglinski wrote:

Hi Rick,

In the Orthogonally section of the latest GTO Keypad manual, it states that:
"especially in GEM mounts, a non-orthogonal mount will cause errors in ANY routine that uses the scope for polar alignment (e.g. N Polar Calibrate routine) ..."

So, I assume this is true for all other routines, including Quick Drift, which does not make it a secondary issue of concern, and certainly necessary. The routine to square it up is essentially identical to the one describing Roland's GTO Quick Star Drift Method using Meridian Delay - except rather than adjusting mount's azimuth adjuster , you use metal shims to prop up the OTA.

The only mention of using the finder is if the mount alignment (or I suppose orthogonally) is way off, and the reference star is out of the field. In such case, the manual states using the finder, for the first iteration, before trying the OTA again.

As far a I can tell, getting the OTA orthogonal is the first concern (assuming it is carrying a finder aligned with its optical axis already). Once the OTA/finder are trued up, you should align the mount.

However, I must say, there seems to be a "chicken and egg" quandary here.
For the Quick Drift Method, you need a properly aligned mount to run the orthogonally test, BUT, the OTA has to be orthogonal to begin with, in order to align the mount.

Based on the east-west drift during that procedure, how do you know whether the drift is caused by a misaligned mount, or a non-orthogonal OTA?

I suppose, you could just assume the OTA is aligned, and IF you can't align the mount after many iterations, ONLY then assume the OTA is non-orthogonal, and repeat the tests, BUT this time use "shims" under the OTA rings, rather than the AZ adjuster.
Does this make sense? I don't recall it being stated this way in the manual.

As for the finder in Roland initial discussion, if it is physically part of the mount, then you still have to run the two procedures for the finder of mount alignment - followed by (if needed), finder orthogonally shimming (i.e screw adjustment).
You can't do the same if the finder is on the OTA, since you could have both the finder and the OTA individually non-orthogonal. That is why it seems best to align the finder with the OTA using a special eyepiece - perhaps in the daylight, on a distant object.

Yikes !



Re: An easier Pasillx N & S Polar Alignment method

Joe Zeglinski
 

Hi Rick,

In the Orthogonally section of the latest GTO Keypad manual, it states that:
"especially in GEM mounts, a non-orthogonal mount will cause errors in ANY routine that uses the scope for polar alignment (e.g. N Polar Calibrate routine) ..."

So, I assume this is true for all other routines, including Quick Drift, which does not make it a secondary issue of concern, and certainly necessary. The routine to square it up is essentially identical to the one describing Roland's GTO Quick Star Drift Method using Meridian Delay - except rather than adjusting mount's azimuth adjuster , you use metal shims to prop up the OTA.

The only mention of using the finder is if the mount alignment (or I suppose orthogonally) is way off, and the reference star is out of the field. In such case, the manual states using the finder, for the first iteration, before trying the OTA again.

As far a I can tell, getting the OTA orthogonal is the first concern (assuming it is carrying a finder aligned with its optical axis already). Once the OTA/finder are trued up, you should align the mount.

However, I must say, there seems to be a "chicken and egg" quandary here.
For the Quick Drift Method, you need a properly aligned mount to run the orthogonally test, BUT, the OTA has to be orthogonal to begin with, in order to align the mount.

Based on the east-west drift during that procedure, how do you know whether the drift is caused by a misaligned mount, or a non-orthogonal OTA?

I suppose, you could just assume the OTA is aligned, and IF you can't align the mount after many iterations, ONLY then assume the OTA is non-orthogonal, and repeat the tests, BUT this time use "shims" under the OTA rings, rather than the AZ adjuster.
Does this make sense? I don't recall it being stated this way in the manual.

As for the finder in Roland initial discussion, if it is physically part of the mount, then you still have to run the two procedures for the finder of mount alignment - followed by (if needed), finder orthogonally shimming (i.e screw adjustment).
You can't do the same if the finder is on the OTA, since you could have both the finder and the OTA individually non-orthogonal. That is why it seems best to align the finder with the OTA using a special eyepiece - perhaps in the daylight, on a distant object.

Yikes !

Joe

----- Original Message -----
From: "Rick K" <JunkMailGoesHere@...>
To: <ap-gto@...>
Sent: Saturday, September 20, 2008 9:12 PM
Subject: [ap-gto] Re: An easier Pasillx N & S Polar Alignment method


I am glad Roland brought up using a finder. The whole point of the
meridian flip method is to polar align the mount. Making the optics
perfectly orthogonal is secondary and unnecessary. It might make
things a little simpler to understand if you do both as Roland
describes, N-S for the inclination error and E-W for the orthogonal
error when using the meridian delay flipping. Using the finder seems
to really speed things up and if one wants to get super accurate,
going to a CCD technique in the main instrument would quickly
fine-tune the polar alignment. I like it!


AP's serial cable and KeySpan USB-to-Serial adapter comments

Phillip Jones
 

Happy to say the serial cable and KeySpan adapter I ordered from AP
worked perfectly with my AP900 GTO. I have a new laptop running Vista
and TheSky v6. Connecting to the mount went smoothly.

I previously had failure after failure when attempting to connect with
serial cables and USB-to-serial adapters from local computer stores.

Glad now AP carries the right cable and adapter.

-Phil


Re: An easier Pasillx N & S Polar Alignment method

observe_m13
 

I am glad Roland brought up using a finder. The whole point of the
meridian flip method is to polar align the mount. Making the optics
perfectly orthogonal is secondary and unnecessary. It might make
things a little simpler to understand if you do both as Roland
describes, N-S for the inclination error and E-W for the orthogonal
error when using the meridian delay flipping. Using the finder seems
to really speed things up and if one wants to get super accurate,
going to a CCD technique in the main instrument would quickly
fine-tune the polar alignment. I like it!


--- In ap-gto@..., "Joseph Zeglinski" <J.Zeglinski@...> wrote:

Hi Rolando,

I too was a bit confused, but let that slip. Now I am really
confused.
I understand your method and the explanation is clear, but I don't
get the
"initial conditions".

Was the main OTA (with finder on top), already perfectly
orthogonal to
the mount, or is the finder physically attached to the AP-3200
mount, and
therefore requires its own alignment? Even with the latter,
adjusting the
mount Alt-Az knobs for the finder, ruins the OTA derived mount
alignment.
Saying:
*
******
The advantage of using the 8x50 finder was that i could quickly
adjust it
via
the thumbscrews to be perfectly orthogonal to the mount (unlike the
Big Mak
which was off about 15 arc minutes).
******

... implies that this was an "initial installation", and the finder
and OTA
were not yet aligned to each other.
I would have started by aligning the finder to the OTA using an
"illuminated cross hair eyepiece", until these two were parallel,
and then
go through your procedure to make the OTA/finder orthogonal with
the mount,
and then also polar aligned.

The way I read this, you are making the (OTA attached) finder
orthogonal
to the mount, and once completed, you then need to repeat for the
main OTA -
which now misaligns the finder.

The only way this explanation would seem right to me - is if you
had
said that the OTA was already previously orthogonal to the mount,
and the
procedure was merely to do the same for the finder.
But that is a harder way to do that than using a cross hair eyepiece
in the
first place. The only saving is the purchase of that special
eyepiece, which
I assume most of us already own.

Thanks for a further clarification.
Joe

----- Original Message -----
From: <chris1011@...>
To: <ap-gto@...>
Sent: Saturday, September 20, 2008 11:54 AM
Subject: Re: [ap-gto] Re: An easier Pasillx N & S Polar Alignment method


The mount's altitude axis
is properly set and the finderscope's adjuster screws are also
properly
set, so
you are 1/2 polar aligned and the finder is perfectly orthogonal.

Rolando


Re: An easier Pasillx N & S Polar Alignment method

Joe Zeglinski
 

Hi Rolando,

I too was a bit confused, but let that slip. Now I am really confused.
I understand your method and the explanation is clear, but I don't get the "initial conditions".

Was the main OTA (with finder on top), already perfectly orthogonal to the mount, or is the finder physically attached to the AP-3200 mount, and therefore requires its own alignment? Even with the latter, adjusting the mount Alt-Az knobs for the finder, ruins the OTA derived mount alignment.
Saying:
*
******
The advantage of using the 8x50 finder was that i could quickly adjust it via
the thumbscrews to be perfectly orthogonal to the mount (unlike the Big Mak
which was off about 15 arc minutes).
******

... implies that this was an "initial installation", and the finder and OTA were not yet aligned to each other.
I would have started by aligning the finder to the OTA using an "illuminated cross hair eyepiece", until these two were parallel, and then go through your procedure to make the OTA/finder orthogonal with the mount, and then also polar aligned.

The way I read this, you are making the (OTA attached) finder orthogonal to the mount, and once completed, you then need to repeat for the main OTA - which now misaligns the finder.

The only way this explanation would seem right to me - is if you had said that the OTA was already previously orthogonal to the mount, and the procedure was merely to do the same for the finder.
But that is a harder way to do that than using a cross hair eyepiece in the first place. The only saving is the purchase of that special eyepiece, which I assume most of us already own.

Thanks for a further clarification.
Joe

----- Original Message -----
From: <chris1011@...>
To: <ap-gto@...>
Sent: Saturday, September 20, 2008 11:54 AM
Subject: Re: [ap-gto] Re: An easier Pasillx N & S Polar Alignment method


The mount's altitude axis
is properly set and the finderscope's adjuster screws are also properly set, so
you are 1/2 polar aligned and the finder is perfectly orthogonal.

Rolando


Re: An easier Pasillx N & S Polar Alignment method- NOW New Gear Cutting Procedu

tucstargzr
 

--- In ap-gto@..., chris1011@... wrote:

In a message dated 9/19/2008 5:41:18 AM Central Daylight Time,
docsquic@... writes:
SNIP
The production worm on this 3600 mount is made with a new gear
cutting method that we developed here after much testing, and it
produced a raw periodic error of under 2 arc seconds without PEM in a
5 minute worm cycle.
<<<<snip

Rolando

Hmmmm, this old fart wonders if you will use the new Gear Cutting
Method on the AP1200s just now entering production?

Tom
Ye Olde Fart from Tucson, AZ


Re: An easier Pasillx N & S Polar Alignment method

Mark Squicquero
 

Joe,

The Helmet cam comes with the necessary attachment gear, and you don't need the DVR setup although I got one with the package I purchased.  The camera comes with the so called "DVR Travel Adapter"  which interfaces to the bottom of the Archos and has a 4 conductor male stereo jack and a power tab.  It can run off of the Archos battery or you can plug in an external 5v power supply.  The DVR station has numerous inputs and outputs.  You can have S-Video in and out, RGB in and out, Composite in and out, as well as usb A and usb mini B.  So the DVR station looks like the way to add another camera with better low light specs.  I was thinking of getting something like a Stellacam 3 so that I could do some video stuff through the scope (after polar aligning of course ;-) .

Mark



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


Re: An easier Pasillx N & S Polar Alignment method

Mark Squicquero
 

Roland,

Great description of the process.  I have one question which probably has an obvious answer:  When you did the first iterations on Vega, you stated that it allowed you to get the finder orthagonal.  I'm not sure what you mean by this and how you insure that it is orthagonal.  Are you adjusting the finder or the alt az adjustments in this first step?  I guess I just need some clarification of the first "slew to Vega" process and what is going on so that I understand the basis for the adjustments.  The initial setup has the mount pointing North, tube level in Park 1, resume from Park1, slew to Vega, then do you adjust the finder so that Vega is centered in the crosshairs?  If so, I'm not sure what the situation is at this point.  Do we asume that the mount is perfectly adjusted and pointing to Vega at this point and make the finder coincide with that asumption?  I know I'm missing something at this step, the rest makes perfect sense.

Mark


AP 130 f/6 on Astromart

Kent Francis
 

I am selling my wonderful AP 130 f/6 Starfire EDF from July 1996 run on
Astromart Ad # 586257. If you have questions please email thru AM as
my Internet is down. Thanks.


Re: An easier Pasillx N & S Polar Alignment method

ayiomamitis
 

--- In ap-gto@..., chris1011@... wrote:

In a message dated 9/19/2008 11:55:21 AM Central Daylight Time,
ayiomami@... writes:


Now eagerly waiting for M13 ..... :-)
Rolando,


It's up on the website in the Gallery section under Roland's test images.
As much as I like pursuing globulars - they are very dramatic objects - I have refrained so
far from chasing them and this is due to the fact that I cannot get good overall colour for
one reason or another. I am almost convinced it is due to the ST-2000XM and I will
certainly be revisiting them with the new gun (ST-10XME).

Case in point is my M13 which we can use for comparison (AP160 vs AP305):
http://www.perseus.gr/Astro-DSO-NGC-6205.htm (please click on the image for a
higher resolution version).

One obvious difference between our results is the colour and where you managed to
capture the older members of the cluster nicely. Even though my result is LRGB with
correction for QE balance (G2V calibration using 16-Cygni) and atmospheric extinction, I
do not have any trace of red and in contrast to your result which is rich in colour and in
spite of the fact you have only 6.7 minutes total data (I had 120 minutes).

Anthony.







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


Re: An easier Pasillx N & S Polar Alignment method

Roland Christen
 

In a message dated 9/20/2008 8:36:40 AM Central Daylight Time,
docsquic@... writes:


When you did the first iterations on Vega, you stated that it allowed you
to get the finder orthagonal. I'm not sure what you mean by this and how you
insure that it is orthagonal
When a scope (or finder in this case) is not orthogonal to the mount, it will
be off by twice the orthogonal error when doing the Meridian Flip. So, using
logic, one starts with Vega perfectly centered on the finder crosshairs in the
East. After the flip, the star will be off N-S due to altitude angle error,
and E-W due to orthogonal error. In both cases one does the exact same thing -
move the star 1/2 way to the crosshair center with the adjusters and bring it
the rest of the way with the N-S and E-W buttons. For the N-S you move the alt
axis screw, for the orthogonal E-W direction you move the finderscope's
adjustment screws. When you are done and the star is perfectly centered on the
crosshairs, you do a Recal to fix this new physical position into the servo as
the actual RA/Dec co-ordinate of Vega.

Now that Vega is again on the crosshair with the scope in the West, do the
iteration again, same way by flipping the scope over to the East. Each iteration
will bring Vega closer to the center of the crosshair. Once it remains
centered on each side of the meridian, you are finished. The mount's altitude axis
is properly set and the finderscope's adjuster screws are also properly set, so
you are 1/2 polar aligned and the finder is perfectly orthogonal.

Rolando


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Re: An easier Pasillx N & S Polar Alignment method

Roland Christen
 

In a message dated 9/19/2008 11:55:21 AM Central Daylight Time,
ayiomami@... writes:


Now eagerly waiting for M13 ..... :-)

It's up on the website in the Gallery section under Roland's test images.






**************
Looking for simple solutions to your real-life financial
challenges? Check out WalletPop for the latest news and information, tips and
calculators.
(http://www.walletpop.com/?NCID=emlcntuswall00000001)


Re: An easier Pasillx N & S Polar Alignment method

Joe Zeglinski
 

Roland ... excellent and reassuring description.

Just like Anthony earlier, I also saved your post as a separate text file to my AP folder, for future reference.
This is definitely - another keeper.

Joe

----- Original Message -----
From: <chris1011@...>
To: <ap-gto@...>
Sent: Friday, September 19, 2008 12:06 PM
Subject: Re: [ap-gto] Re: An easier Pasillx N & S Polar Alignment method


In a message dated 9/19/2008 5:41:18 AM Central Daylight Time,
docsquic@... writes:


With the right camera and fine enough control over the reticle brightness
this could be a really neat comercial product for those of us who hate to
kneel before our AP1200's ;-)
Howard and myself set up a 3600 mount last night from scratch, polar aligned
it and began imaging by 8pm, just after evening twilight. We were able to do
unguided imaging with a focal length of 3810 mm (12" F12.5 Mak-Cass), achieving
FWHM stars of 1.8 arc seconds on M13. The seeing wasn't the greatest and
there were thin high clouds, but the real achievement was to do the polar
alignment without using a polar scope or drift alignment, and still be able to get the
alignment dead nuts accurate for unguided imaging.
<snip>


Re: question re a preplanned observing session...

ebuehrens
 

Phil, you should look at SkyTools
(http://www.skyhound.com/skytools.html) by Greg Crinklaw. It's not
clear from your message whether you want to simply avoid punching RA &
DEC info into the keypad for every star, or actually script the mount
to move through a sequence of objects without human intervention, as
would be desirable for a remote observatory. SkyTools does the former
brialliantly, and building an observing list filtered for the
variables you want to observe is very straightforward and rapid. Then
you use the SkyTools "RealTime" plugin, which is an ASCOM driver, to
drive the mount. Slewing from object to object is by pushing the space
bar on your laptop - it could not be easier.

It does not do scripting but there is a new version about to be
released that will emphasize imaging capabilities more - perhaps this
will be added. It's pretty much all I use for visual observing with my
AP1200 and 10" Mak-Cass.

Eric
www.taconicobservatory.com

--- In ap-gto@..., "philipdombrowski"
<phil.dombrowski@...> wrote:

Dear Howard, Roland & any group member that knows the answer to my
question....
If I am doing a nightly sequence of variable star observations is
there a way to have a preplanned (pre-programmed) sequence of targets
so that I can simply go from one star to the next without having to
enter the RA & DEC of each target star? On any given night I may want
to do 15 variable stars and it would be most desirable to go from one
star to the next without the re entering of coordinates. Earlier
Vstar observers would likely tell me that a "good" observer would just
know how to get from one star to the next from my knowledge of the
night sky! However, I would like to take advantage of the AP1200's
full capabilities. Many of my target stars are in fields were I am
looking for a target that my only be 12th mag or fainter. A feature
that may already be on the AP1200 that I am unaware of would be rather
"cushy".
I very much appreciate your response.
Phil Dombrowski
Glastonbury, CT