Tripod & Mount Needed

On Monday, February 15, 2016 at 5:00:54 AM UTC, palsing wrote:
On Sunday, February 14, 2016 at 12:08:39 PM UTC-8, oriel36 wrote:

GoTo telescopes and tracking using the average 24 hour day is actually a homocentric exercise although the mounts given the impression that they are following the daily rotation of the Earth.

If you own a telescope that tracks using the average 24 hour day, then you have a drive that has a solar setting... which is included only so you can track the Sun. On the other hand, if you want your telescope to track a star (any star in the sky of your choice), then it must also have a sidereal rate, which is 23 56 04... otherwise, you will fail. Some drives also have a lunar rate, which is different from both the solar rate and the sidereal rate, and it allows you to track the moon (what a surprise!).

Different rates for different objects, these are the cold, hard facts of life. There is no sidereal vs solar vs lunar drama, your own views notwithstanding.

Too bad you remain totally unteachable, your loss... so sad... unlock your brain and finally enjoy reality...

Know your place boy.

You are full of stock phrases common to old men who have lost the ability to reason and enjoy life and the connection to the celestial arena.

The Earth has a maximum equatorial speed of 1037.5 miles per hour and once in 24 hours via the 24 hour system and the Lat/Long system so assigning different rotations rates to all celestial objects is merely an extension of the original notion of splitting rotation to the Sun and rotation to the stars as two different rotations.

What people should know is that the Earth has two distinct rotations to the central Sun corresponding to two separate day/night cycles and where these day/night cycles combine we get the seasons. It is actually observable on another planet where the unique traits allow the greatest telescope to see the slower orbital component of rotation contrasted against the faster daily rotation -

https://www.youtube.com/watch?v=612gSZsplpE

Your stock phrases are a symptom of a petrified brain because there are no cold,hard facts, there are the enjoyable reasons which link timekeeping to the planetary cycles without subverting how they come into close proximity.

In two weeks exactly the 24 hour day and rotation will close out 4 annual circuits of the Earth around the Sun and it is derived from a parent observation that the proportions of rotations to annual cycles is 1461 rotations to four annual circuits and 365 1/4 rotations per orbital circuit.

Thanks for your comments.

I donet care about rotation BUT -

An alt azm mount will require active, 2 motors in 2 axis, coordinated
software and larger power supply. Of course it will be smaller,
lighter and cheaper which are definite advantages.

I've used both, manually and powered and prefer the equitorial.

So far I've only ordered mounting plate which will work with either. I
want to check this hardware where I have some doubts. No rush. Scope
has mounting bolt holes spaced 6 3/8 ".

Keeping an open mind.

Steve

On Sun, 14 Feb 2016 12:29:10 -0700, Chris L Peterson
wrote:

On Sun, 14 Feb 2016 14:06:19 -0500, wrote:

Well, I'm thinking equitorial because I'd want to stay with the same
object while others take looks and I shift eyepieces, etc. Might want
a drive in the equitorial axis ...

You only need equatorial if you need to maintain the rotational
orientation in the eyepiece, as when you image. For visual use,
orientation isn't important, nor is the fact that the view slowly
rotates over time. What you want is _tracking_, and modern altaz
mounts provide excellent tracking. So with an iOptron mount like the
one I suggested, the scope will track the target all night long. It
will initially point the scope to your desired target, either by
coordinates or some catalog ID in its database, and keep it there as
long as you want.

Chris L Peterson wrote:
On Sun, 14 Feb 2016 14:06:19 -0500, wrote:

Well, I'm thinking equitorial because I'd want to stay with the same
object while others take looks and I shift eyepieces, etc. Might want
a drive in the equitorial axis ...

You only need equatorial if you need to maintain the rotational
orientation in the eyepiece, as when you image. For visual use,
orientation isn't important, nor is the fact that the view slowly
rotates over time. What you want is _tracking_, and modern altaz
mounts provide excellent tracking. So with an iOptron mount like the
one I suggested, the scope will track the target all night long. It
will initially point the scope to your desired target, either by
coordinates or some catalog ID in its database, and keep it there as
long as you want.


It seems fairly trivial to use software to rotate the image so why it an
altaz for imaging.

Mike Collins wrote:
Chris L Peterson wrote:
On Sun, 14 Feb 2016 14:06:19 -0500, wrote:

Well, I'm thinking equitorial because I'd want to stay with the same
object while others take looks and I shift eyepieces, etc. Might want
a drive in the equitorial axis ...

You only need equatorial if you need to maintain the rotational
orientation in the eyepiece, as when you image. For visual use,
orientation isn't important, nor is the fact that the view slowly
rotates over time. What you want is _tracking_, and modern altaz
mounts provide excellent tracking. So with an iOptron mount like the
one I suggested, the scope will track the target all night long. It
will initially point the scope to your desired target, either by
coordinates or some catalog ID in its database, and keep it there as
long as you want.


It seems fairly trivial to use software to rotate the image so why it an
altaz for imaging.




"Why not" not "why it". I'm getting tired of predictive text changing my
posts.

Yep, already ordered a mounting plate from them'


On Sun, 14 Feb 2016 21:52:09 -0800 (PST), RichA
wrote:

On Sunday, 14 February 2016 10:23:34 UTC-5, wrote:
I am the lucky owner of an Astro-Physics 105mm f/5.8 "Traveler"
refractor. I need : tripod, mount (equitorial?), mounting hardware.
Some goto features would be welcome.

I querried Astro-Physics, and got no response !

Any good advice most welcom & thanks.

There are many mounts suitable for you. Check out this company:

http://www.ioptron.com/category-s/100.htm

On Mon, 15 Feb 2016 16:59:52 -0000 (UTC), Mike Collins
wrote:

Chris L Peterson wrote:
On Sun, 14 Feb 2016 14:06:19 -0500, wrote:

Well, I'm thinking equitorial because I'd want to stay with the same
object while others take looks and I shift eyepieces, etc. Might want
a drive in the equitorial axis ...

You only need equatorial if you need to maintain the rotational
orientation in the eyepiece, as when you image. For visual use,
orientation isn't important, nor is the fact that the view slowly
rotates over time. What you want is _tracking_, and modern altaz
mounts provide excellent tracking. So with an iOptron mount like the
one I suggested, the scope will track the target all night long. It
will initially point the scope to your desired target, either by
coordinates or some catalog ID in its database, and keep it there as
long as you want.


It seems fairly trivial to use software to rotate the image so why it an
altaz for imaging.

Certainly, most large professional scopes are altaz with rotators. And
while the motion control is simple in principle, in practice it would
add a lot of cost to a small mount. An equatorial mount only requires
accurate, low-noise tracking on a single axis. The other axis can be
much simpler mechanically, as it is only tweaked occasionally in
response to a guider signal.

An altaz mount used for imaging requires accurate, low-noise control
of three axes. It also has a singularity at the zenith (where it can't
track), which is generally a bigger problem for imagers than the polar
singularity of an equatorial mount.

Chris L Peterson wrote:
On Mon, 15 Feb 2016 16:59:52 -0000 (UTC), Mike Collins
wrote:

Chris L Peterson wrote:
On Sun, 14 Feb 2016 14:06:19 -0500, wrote:

Well, I'm thinking equitorial because I'd want to stay with the same
object while others take looks and I shift eyepieces, etc. Might want
a drive in the equitorial axis ...

You only need equatorial if you need to maintain the rotational
orientation in the eyepiece, as when you image. For visual use,
orientation isn't important, nor is the fact that the view slowly
rotates over time. What you want is _tracking_, and modern altaz
mounts provide excellent tracking. So with an iOptron mount like the
one I suggested, the scope will track the target all night long. It
will initially point the scope to your desired target, either by
coordinates or some catalog ID in its database, and keep it there as
long as you want.


It seems fairly trivial to use software to rotate the image so why it an
altaz for imaging.

Certainly, most large professional scopes are altaz with rotators. And
while the motion control is simple in principle, in practice it would
add a lot of cost to a small mount. An equatorial mount only requires
accurate, low-noise tracking on a single axis. The other axis can be
much simpler mechanically, as it is only tweaked occasionally in
response to a guider signal.

An altaz mount used for imaging requires accurate, low-noise control
of three axes. It also has a singularity at the zenith (where it can't
track), which is generally a bigger problem for imagers than the polar
singularity of an equatorial mount.


I'm not suggesting physical rotation of the eyepiece. It would be easy for
stacking software to rotate the image eliminating the need for physical
rotation. I don't know if this is available but it shouldn't be too
difficult to write compared to the rest of the stacking code.

On Mon, 15 Feb 2016 23:08:19 -0000 (UTC), Mike Collins
wrote:

I'm not suggesting physical rotation of the eyepiece. It would be easy for
stacking software to rotate the image eliminating the need for physical
rotation. I don't know if this is available but it shouldn't be too
difficult to write compared to the rest of the stacking code.

Physical rotation of the imager is a requirement for anything other
than video imaging. Polar rotation becomes an issue in as little as a
few tens of seconds at typical imager resolutions. That means that if
you want to rotate and stack frames (which is trivial and performed by
many apps) you need to limit your exposure time to much less than the
optimum length set by sky background level (typically a few minutes to
a few tens of minutes). Such short exposures mean that you're really
take a S/N hit from readout noise.

People who are imaging with altaz mounts generally add an image
rotator accessory so they can make reasonable length subs.

Chris L Peterson wrote:
On Mon, 15 Feb 2016 23:08:19 -0000 (UTC), Mike Collins
wrote:

I'm not suggesting physical rotation of the eyepiece. It would be easy for
stacking software to rotate the image eliminating the need for physical
rotation. I don't know if this is available but it shouldn't be too
difficult to write compared to the rest of the stacking code.

Physical rotation of the imager is a requirement for anything other
than video imaging. Polar rotation becomes an issue in as little as a
few tens of seconds at typical imager resolutions. That means that if
you want to rotate and stack frames (which is trivial and performed by
many apps) you need to limit your exposure time to much less than the
optimum length set by sky background level (typically a few minutes to
a few tens of minutes). Such short exposures mean that you're really
take a S/N hit from readout noise.

People who are imaging with altaz mounts generally add an image
rotator accessory so they can make reasonable length subs.


Thanks for the reply.

On Monday, February 15, 2016 at 10:06:29 PM UTC, Chris L Peterson wrote:
On Mon, 15 Feb 2016 16:59:52 -0000 (UTC), Mike Collins
wrote:

Chris L Peterson wrote:
On Sun, 14 Feb 2016 14:06:19 -0500, wrote:

Well, I'm thinking equitorial because I'd want to stay with the same
object while others take looks and I shift eyepieces, etc. Might want
a drive in the equitorial axis ...

You only need equatorial if you need to maintain the rotational
orientation in the eyepiece, as when you image. For visual use,
orientation isn't important, nor is the fact that the view slowly
rotates over time. What you want is _tracking_, and modern altaz
mounts provide excellent tracking. So with an iOptron mount like the
one I suggested, the scope will track the target all night long. It
will initially point the scope to your desired target, either by
coordinates or some catalog ID in its database, and keep it there as
long as you want.


It seems fairly trivial to use software to rotate the image so why it an
altaz for imaging.

Certainly, most large professional scopes are altaz with rotators. And
while the motion control is simple in principle, in practice it would
add a lot of cost to a small mount. An equatorial mount only requires
accurate, low-noise tracking on a single axis. The other axis can be
much simpler mechanically, as it is only tweaked occasionally in
response to a guider signal.

An altaz mount used for imaging requires accurate, low-noise control
of three axes. It also has a singularity at the zenith (where it can't
track), which is generally a bigger problem for imagers than the polar
singularity of an equatorial mount.

You are amazing people in the strangest possible way in how you can simply ignore the principles of timekeeping and how to come into a close proximity to daily and orbital dynamics. It is an illness of course,after all, the inability to put the day/night cycle in context of one rotation is at a level nobody can imagine, not with the strongest effort -

http://hypertextbook.com/facts/1999/JennyChen.shtml


I would have thought the upcoming attraction of the 24 hour day and rotation of February 29th would draw observers into looking at the line-of-sight observation which strips stellar circumpolar of any significance and allows the Earth's orbital motion alone to account for the passage of the backgrounds stars behind the Sun in sequence -

https://www.youtube.com/watch?v=eeQwYrfmvoQ

What a wondrous sight, the observation which affirms the Sun is central and the orbital input of the Earth when it comes to the inner planets and not a single individual cares enough to get behind this insight in general or in detail.

You are the rest of the celestial sphere dummies have spent decades managing to ignore what is effectively the easiest possible interpretation in astronomy for nothing other than the clockwork solar system of the late 17th century guys.