A beginners mount question.

[Quacker64]

As some might know I'm looking to purchase my first scope very soon and have decided to make it a Mak 127 with Synscan GOTO. This is on or includes an ALT AZ mount. Mounts are new to me. My only precious experience being spotters scopes and SLR, DSLR and digiscoping. They were just various tripods with little more than pan and tilt. Perfectly adequate for birding etc.

Aside from the (cheaper) cost, are there any pros or cons I should be aware of, limitations and so on? - or perhaps a better way to word the question is what do other mounts such as EQ and the like (not even sure of the correct terms) add or bring to the party? I know they are more expensive but can anyone explain why or as a complete beginner is it something not to concern myself with as I look to purchase my first scope?

It's still not too late before ordering or is it something I might be more interested in later into my astronomy career?

I'm getting the gist of EP's and even the scopes themselves.

Steve

[Quacker64]

Apologies, posted twice - mods please remove, sorry.

[jambouk]

It's a good question to ask, and a multi component one to answer.

The mount is great. Once you get your head around it, it is a very capable mount when combined with that scope. The goto accuracy is pretty good. It will serve you well for observing and for planetary and lunar [and solar] imaging should you wish. If you want to inage deep sky objects like galaxies and nebula, it is less good because it is an alt-azimuth mount and your imaging exposures will be limited to 10 seconds or so due to "field rotation" (look it up). But then the scope isn't ideal for those objects for imaging anyway as it has relatively "slow" optics (being f/12 or whatever, compared to a fast scope like an f/5 one (again stuff to look up)). The mount is a bit noisy, and there is a learning curve, but is a cracking first mount for visual and solar system imaging.

An equatorial mount with goto will cost a fair bit more; not sure exactly how much more. It has its own learning curve, but its not difficult. An equatorial mount will result in less field rotation, so you can in theory take long exposures, but the very basic goto equatorial mounts will be imperfect and you'll still be limited to well under a minute i suspect woth the long focal length of that scope (the longer the focal length, the more apparent tracking errors are in your inages, a short focal length scope would probably have a focal length under 600mm, though others with more knowledge may disagree with that precise number). An equatorial mount is probably a little trickier to get ones head around than an alt-azimuth one, but it's no biggie really. The more you can spend on an equatorial mount, the better it will track, and allow you to take longer exposures - long exposures generally mean more photons which means more detail. But at some point, the intrinsic tracking of the mount will be pushed to the limit, and you'd need to start ising a guiding set up ( essentially a second scope to make sure the first scope stays exactly on its target for hours on end).

So if you just want to do visual and solar sustem imaging, this mount is a cracking good buy and will serve you well.

If you want to get into imaging DSOs, then you need a good quality EQ mount (like an HEQ5 or better) and probably a different [shorter focal length, faster] scope.

Ideally get to a star party and look theough a 127, and see how easy or not the mount is to set up and run, vs an equatorial mount.

If you are anywhere near Nottingham, you are welcome to come and look at an equatorial mount, and the alt-az mount you are looking at.

Good luck.

James

[Kropster]

Mounts can be confusing.

Here is my (limited) understanding..

An EQ mount is able to track stars by rotating around an axis aligned with the celestial pole.

It only needs to rotate about this one axis to do this....effectively cancelling out the rotation of the Earth on its axis.

An Alt-Az mount has to be moved about two axes to track a star and will rotate the field of view as it does so.

This makes the Alt-Az mount unsuitable for long exposure astrophotography, should you ever wish to get into it.

...as I understand it  :-)

[Stu]

I guess the key question is do you intend to do any long exposure Astro Photography or not?

If the answer is no, or just lunar/planetary imaging then an alt az will be fine.

An EQ mount offers a number of advantages, possibly most significant is that it doesn't suffer from field rotation when taking long exposures. Even if AP is a future aim, the 127 isn't necessarily the best starting point so I would probably consider this separately.

There are no straightforward answers, but if you give author detail about your future ambitions/goals it will help.

[John]

Apologies, posted twice - mods please remove, sorry.

I've merged the 2 threads because you had responses to both of them !

[brantuk]

If you intend to image dso's then this is not the best scope/mount combination to do so. It's a good combination for imaging solar system objects (planets, moon, sun, etc) because you have a long focal length in the Mak and alt/az mounts are fine for "near" objects, which are bright, and good for short exposures and fast frame video work.

For dso imaging however (as mentioned above) you would need long exposures, polar alignment, and single plane tracking given by an EQ mount (long exposure meaning 5, 10, 20mins and more per frame). With dimmer objects you also need a scope with a shorter focal ratio, and wider field of view to accommodate fainter and larger objects. Also some ccd imaging cameras can be very expensive - though you can start with dslr's.

You can of course do observing of all objects with any scope but they will perform better depending on aperture, and focal length. Beware that shorter focal ratios require better optics which means eyepieces can get expensive - often costing more than the scope and mount put together per eyepiece. Hth

[ollypenrice]

For visual I greatly prefer a computerized and driven Alt Az on the grounds of ease and comfort. For deep sky AP I have to use an equatorial and that's that. But beware, I also have to use a good equatorial because a basic one won't do the job in practice.

Olly

[Quacker64]

Thanks for all the answers and the especially the kind offer James. Although you're quickly becoming my online mentor or "Elmer" (as they say in the states) Nottingham is about 150 mile south of here lol. General consensus would seem to be Alt Az fine for viewing but a good quality EQ for imaging. Obviously as a rule of thumb.

Already my little brain is formulating the 2nd scope and setup requirements...... Well nothing like a bit of advanced planning. Then we can discuss EQ mounts in the relevant section of course ;-)

[cjdawson]

As some might know I'm looking to purchase my first scope very soon and have decided to make it a Mak 127 with Synscan GOTO. This is on or includes an ALT AZ mount. Mounts are new to me. My only precious experience being spotters scopes and SLR, DSLR and digiscoping. They were just various tripods with little more than pan and tilt. Perfectly adequate for birding etc.

Aside from the (cheaper) cost, are there any pros or cons I should be aware of, limitations and so on? - or perhaps a better way to word the question is what do other mounts such as EQ and the like (not even sure of the correct terms) add or bring to the party? I know they are more expensive but can anyone explain why or as a complete beginner is it something not to concern myself with as I look to purchase my first scope?

It's still not too late before ordering or is it something I might be more interested in later into my astronomy career?

I'm getting the gist of EP's and even the scopes themselves.

Steve

I've decided not to look at the other posts on this thread, so that you can get my unrefined opinion  (It'll also be interesting to see how this lines up/differs from what others are saying, should be fairly similar)

Basically there are two types of mount.

Alt-Az mounts and EQ mounts.

Alt-Az are like camera tripods.  The part were you attach the camera is tends to be level with the ground, they can rotate, left right, up and down. The important part here is that their left right (Azimuth) movement will track along the horizon.  The Alt is literally up and down.  This is great for daytime photography.   But not good for astro photography.   With a Goto scope, the object will be tracked by the computer, it'll run both the Alt and the Az motors to keep the star in place as time passes.

EQ mounts are a modification on the Alt-Az system.  What is does is tilt the part that you attach the camera to so as to fool the camera into thinking that that it is sitting on the north pole.  This is important as by doing this means that the "left right" motion will be in line with the motion of the stars.    During the course of the night, the stars will appear to rotate over your head.  This rotation is caused because you are not at the north pole.  The stars are not moving, the earth is spinning.  What these mounts do is rotate the scope, in the same motion as the stars move across the sky.  Because of this tilt, we tend to talk about Right Ascension, and Declination so as not to confuse people  - there are mathematics that can be employed to convert between RA and Azimuth which tends to be rather complicated.  For an EQ mount, only the RA motor will need to run to track the star. 

Alt-Az

Pro's

• great for visual observing.  
• They are much simpler to setup and use.
• With mounts like the one for he Meade LX-90, the scope is attached to the tripod directly, which is more secure - so will vibrate less.

Con's

• Stars will rotate in the field of view as time passes.
• Both motors, Alt and Az need to move in order to track a target

EQ mounts

Pro's

• Good for both visual and photographic use.
• Stars will not rotate in the field of view
• The tilt compensates for the earth's rotation - only the RA motor needs to run.

Con's

• On a fork mount, a wedge is needed, this can change the scope making it slightly less stable (more wobbles)
• More complicated to setup - you need to align to the celestial pole (neither the north or south pole has a star, polaris is close, but not perfect)

[happy-kat]

Lastly as far as I have derived eq mounts are often heavier and have more bits with the counter weight bar and weights.

Also consider storage location to observing location. The greater the distance and/or stairs the heavier the setup and/or lots of bits might mean not grabbing the gaps between clouds.

[Quacker64]

I've decided not to look at the other posts on this thread, so that you can get my unrefined opinion  (It'll also be interesting to see how this lines up/differs from what others are saying, should be fairly similar)

Basically there are two types of mount.

Alt-Az mounts and EQ mounts.

Alt-Az are like camera tripods.  The part were you attach the camera is tends to be level with the ground, they can rotate, left right, up and down. The important part here is that their left right (Azimuth) movement will track along the horizon.  The Alt is literally up and down.  This is great for daytime photography.   But not good for astro photography.   With a Goto scope, the object will be tracked by the computer, it'll run both the Alt and the Az motors to keep the star in place as time passes.

EQ mounts are a modification on the Alt-Az system.  What is does is tilt the part that you attach the camera to so as to fool the camera into thinking that that it is sitting on the north pole.  This is important as by doing this means that the "left right" motion will be in line with the motion of the stars.    During the course of the night, the stars will appear to rotate over your head.  This rotation is caused because you are not at the north pole.  The stars are not moving, the earth is spinning.  What these mounts do is rotate the scope, in the same motion as the stars move across the sky.  Because of this tilt, we tend to talk about Right Ascension, and Declination so as not to confuse people  - there are mathematics that can be employed to convert between RA and Azimuth which tends to be rather complicated.  For an EQ mount, only the RA motor will need to run to track the star. 

Alt-Az

Pro's

• great for visual observing.  
• They are much simpler to setup and use.
• With mounts like the one for he Meade LX-90, the scope is attached to the tripod directly, which is more secure - so will vibrate less.

 

Con's

• Stars will rotate in the field of view as time passes.
• Both motors, Alt and Az need to move in order to track a target

 

EQ mounts

Pro's

• Good for both visual and photographic use.
• Stars will not rotate in the field of view
• The tilt compensates for the earth's rotation - only the RA motor needs to run.

 

Con's

• On a fork mount, a wedge is needed, this can change the scope making it slightly less stable (more wobbles)
• More complicated to setup - you need to align to the celestial pole (neither the north or south pole has a star, polaris is close, but not perfect)

Thanks for taking the time and making the effort to reply. That was a comprehensive answer and I'm happy my first purchase will be Alt Az with the Mak 127 GOTO setup as I have no great urge or plans to get into AP immediately (though I have a canon 350 lying around gathering dust ).

Now I know why second scopes and especially tripods and mounts are almost de-rigeur ;-)

[cjdawson]

No problem.  Glad you found it useful.   With that mount, I don't think EQ will be an option for the future.  But, don't rule it out for any astro photography.  You can do lunar shots with it.  Also you should be able to do something with the larger planets - Jupiter, Saturn, Mars, Venus and Mercury.  All those only need short exposures, so field rotation won't be much of an issue - unless you start trying to stack images or anything like that.  Not to mention adding a solar filter, then the sun is within range too. ;-)

[Quacker64]

No problem.  Glad you found it useful.   With that mount, I don't think EQ will be an option for the future.  But, don't rule it out for any astro photography.  You can do lunar shots with it.  Also you should be able to do something with the larger planets - Jupiter, Saturn, Mars, Venus and Mercury.  All those only need short exposures, so field rotation won't be much of an issue - unless you start trying to stack images or anything like that.  Not to mention adding a solar filter, then the sun is within range too. ;-)

Sort of start off simple and expand as and when necessary.

Makes sense. Not sure what the next one will be, but 3.5 months to Christmas means I know when it might be;-)