slewing sound level


Rich N. <rnapo@...>
 

Last weekend was the first time I tried slewing
my AP 900GTO mount. I was a little surprised
at the noise level when slewing at 1200 and 900.
A friend was using his 1200GTO the same night
and it gave virtually the same sound on the 1200
setting. It made me wonder long the gears and
motors would last slewing like that. I'm sure it
will hold up well.

I didn't try any lower settings. Maybe they are quite
a bit quieter? Sorry to say the Nexstar 5s and 8s
are quieter. Although I'm sure they are not as
accurate or as rugged as the AP mounts.

Maybe I need to read more about using the AP software,
but, having to make a number of passes between Polaris
and another star to polar align seems like a lot of work if
you are not trying to take long exposure astro photos.

Rich


Jeffrey D. Gortatowsky <mrrockets@...>
 

Rich,

I ditched a message that had the exact same tone as yours. After rereading
the original I realized whomever it was posting (grayfox65?) was trying to
get way more precision than I currently need. I mean it was _great_ to get
all this information, and I did file it away, but I was thinking to myself:

"Hello! I just want to slew and have the object in the FOV of
a
31mm Terminagler, not a 2.5mm LV with a 5x PowerMate! :^D
Can't I do a quick two star alignment and start observing?
Then
maybe refine the mount's error by using a synchronize
command?"

However reading the entire message again I see that is exactly the case. So
I trashed the email. I think we are talking about two different criteria for
pointing accuracy here. Me thinks grayfox65 wants to put it on a CCD chip or
somptin' like that. Or I could just be out in left field.

Clear skies,
Jeff

----- Original Message -----
From: "Rich N." <rnapo@znet.com>
To: <ap-gto@egroups.com>
Sent: Tuesday, April 11, 2000 7:00 PM
Subject: [ap-gto] slewing sound level


<snip>
Maybe I need to read more about using the AP software,
but, having to make a number of passes between Polaris
and another star to polar align seems like a lot of work if
you are not trying to take long exposure astro photos.

Rich


Ron Wodaski <ronw@...>
 

Roland says you can do a one-star alignment if you are either already polar
aligned, or don't care to increase the accuracy of your rough alignment. To
do this, start the two-star alignment, and quit after the first star. The
mount will cheerfully accept. I haven't tried this yet, but it would a great
convenience for casual observing: all the benefits of the goto features
without the hassle of a precision polar alignment.

As an alternative, if your polar alignment is very rough, Roland suggested
using the Tour to align on the brightest star in a constellation; you will
then be able to goto other objects in the constellation with a wide-angle
eyepiece, even if polar alignment is quite bad. In effect, you've got a
"local" alignment that suffices for observing in a small area of the sky. If
you move to another area, a quick recalibration for that constellation
should do the trick.

Next time I am out observing, I will take detailed notes on how this works
and post them. I'm in Seattle, so who knows when that will be; if someone
does it first, my heart will survive. <g>

Ron Wodaski

-----Original Message-----
From: Jeffrey D. Gortatowsky [mailto:mrrockets@home.com]
Sent: Tuesday, April 11, 2000 7:39 PM
To: ap-gto@egroups.com
Subject: Re: [ap-gto] slewing sound level


Rich,

I ditched a message that had the exact same tone as yours. After rereading
the original I realized whomever it was posting (grayfox65?) was trying to
get way more precision than I currently need. I mean it was _great_ to get
all this information, and I did file it away, but I was thinking to myself:

"Hello! I just want to slew and have the object in the FOV of
a
31mm Terminagler, not a 2.5mm LV with a 5x PowerMate! :^D
Can't I do a quick two star alignment and start observing?
Then
maybe refine the mount's error by using a synchronize
command?"

However reading the entire message again I see that is exactly the case. So
I trashed the email. I think we are talking about two different criteria for
pointing accuracy here. Me thinks grayfox65 wants to put it on a CCD chip or
somptin' like that. Or I could just be out in left field.

Clear skies,
Jeff

----- Original Message -----
From: "Rich N." <rnapo@znet.com>
To: <ap-gto@egroups.com>
Sent: Tuesday, April 11, 2000 7:00 PM
Subject: [ap-gto] slewing sound level


<snip>
Maybe I need to read more about using the AP software,
but, having to make a number of passes between Polaris
and another star to polar align seems like a lot of work if
you are not trying to take long exposure astro photos.

Rich


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Rich N. <rnapo@...>
 

Thanks Ron. What slew rate do you usually use?
At 1200 and 900 the Dec motor sounds like it is
really working. I felt like I was wearing it out just
doing about four passes (eight slews) back and forth between
Pollux and Polaris to get a semi good polar alignment.

Rich


Roland says you can do a one-star alignment if you are either already polar
aligned, or don't care to increase the accuracy of your rough alignment. To
do this, start the two-star alignment, and quit after the first star. The
mount will cheerfully accept. I haven't tried this yet, but it would a
great
convenience for casual observing: all the benefits of the goto features
without the hassle of a precision polar alignment.


Derek Wong <dawong@...>
 

"Jeffrey D. Gortatowsky" wrote:

"Hello! I just want to slew and have the object in the FOV of
a 31mm Terminagler, not a 2.5mm LV with a 5x PowerMate! :^D
Can't I do a quick two star alignment and start observing?
For visual observing without GOTO, I just sight Polaris through the
polar scope hole and power up.

If I want to use GOTO with fairly good accuracy, I align with the polar
scope then calibrate--no iterations needed. That is good enough to get
well inside the field of a decent sized eyepiece.

Derek


J. L. Schenz <deltatec@...>
 

Derek,

Your operative words were:

"If I want to use GOTO with fairly good accuracy, I align with the polar
scope then calibrate--no iterations needed."

Oh where,oh where can a polar scope be found?  ; ^)

Jim Schenz

Derek Wong wrote:

"Jeffrey D. Gortatowsky" wrote:
>
> "Hello! I just want to slew and have the object in the FOV of
> a 31mm Terminagler, not a 2.5mm LV with a 5x PowerMate!  :^D
> Can't I do a quick two star alignment and start observing?

For visual observing without GOTO, I just sight Polaris through the
polar scope hole and power up.

If I want to use GOTO with fairly good accuracy, I align with the polar
scope then calibrate--no iterations needed.  That is good enough to get
well inside the field of a decent sized eyepiece.

Derek



--
James L. Schenz

Delta Technologies, Limited
13960 North 47th Street
Stillwater, MN  55082-1234
USA

Phone: +651.439.5741
Fax: +651.351.7601
Email: jschenz@...

http://www.delta-technologies.com
 


Paul Hyndman <pghyndman@...>
 

Hi Jim,
 
Some of the servers have been up, down (and all around!) this past week , so you may have missed Marj's posting about the polar allignment scopes on the 7th... it was:
 
"We are finalizing arrangements for a new polar scope which I hope to have by the summer. We will send notice to all people who have purchased GTO mounts and anyone else who is interested. Will also post on the web site.
Marjorie Christen
Astro-Physics"
 
So there ya' have it!
 
Paul

----- Original Message -----
Sent: Wednesday, April 12, 2000 10:20 AM
Subject: Re: [ap-gto] slewing sound level

Derek,

Your operative words were:

"If I want to use GOTO with fairly good accuracy, I align with the polar
scope then calibrate--no iterations needed."

Oh where,oh where can a polar scope be found?  ; ^)


ericj <ericj@...>
 

Rich N. wrote:

I was a little surprised
at the noise level when slewing at 1200 and 900.

Hi Rich:

I had the same impression, but thought it was because I was use to using my
Dob mount, which barely makes a sound as I manually slew from one part of
the sky to another. From what you and your friend noted it seems like this
level of noise is normal.

Clear Skies,

Eric


Marc Zukoff <yooody@...>
 

I have a 400 gto mount on order but would like to educate myself on
the mount before its arrival. Would someone explain the alignment
process for visual use in lower powered fov, and how long the methods
took. Does the mount come with a polar alignment scope?. How about
alignment without sighting polaris?. I currently use an ultima 2000
which is aligned quickly in alt-azm, and is actually very
quiet.Thanks. -- In ap-gto@egroups.com, "Jeffrey D. Gortatowsky"
<mrrockets@h...> wrote:
Rich,

I ditched a message that had the exact same tone as yours. After
rereading
the original I realized whomever it was posting (grayfox65?) was
trying to
get way more precision than I currently need. I mean it was _great_
to get
all this information, and I did file it away, but I was thinking to
myself:

"Hello! I just want to slew and have the object in
the FOV of
a
31mm Terminagler, not a 2.5mm LV with a 5x
PowerMate! :^D
Can't I do a quick two star alignment and start
observing?
Then
maybe refine the mount's error by using a synchronize
command?"

However reading the entire message again I see that is exactly the
case. So
I trashed the email. I think we are talking about two different
criteria for
pointing accuracy here. Me thinks grayfox65 wants to put it on a
CCD chip or
somptin' like that. Or I could just be out in left field.

Clear skies,
Jeff

----- Original Message -----
From: "Rich N." <rnapo@znet.com>
To: <ap-gto@egroups.com>
Sent: Tuesday, April 11, 2000 7:00 PM
Subject: [ap-gto] slewing sound level


<snip>
Maybe I need to read more about using the AP software,
but, having to make a number of passes between Polaris
and another star to polar align seems like a lot of work if
you are not trying to take long exposure astro photos.

Rich