"Outdated" Mounts

[Kenza]

First of all, let me say that from the moment I started observing and imaging I always dreamed of owning an Astrophysics mount. I don't know why, I guess it's one of those unaccountable things. The thing is that now I have a chance of buying one, specifically the GTO 900. Up till now I have imaged with the EQ6 (which is great, really) so i don't have a lot of experience with highest quality mounts. Every now and then I hear on the forum that the AP mounts are "outdated" and old. What does that mean exactly, and if this is so how can they at all be compared to the newer Paramount and 10Micron mounts?

[andrew s]

Over the years I have always had old style mounts. Fullerscope MkI and IV, Parallax with AP control system, AP900 and Paramount ME. All had conventional worm a wheel drives and the last three with servomotor control system and worked perfectly in practice for pointing and tracking. "Modern" mounts variously add on axis encoders and or direct drives or belt drives. These may have some advantages if say you want to do unguided exposures. 

In my view, and looking at the results people get, any top quality mount, old school or new school, can perform practically perfectly. In the end it depends on exactly what you want the mount to do i.e. remote operation, guided or not, image scale, size of scope etc..

Regards Andrew

[ChrisLX200]

2 hours ago, Kenza said:

First of all, let me say that from the moment I started observing and imaging I always dreamed of owning an Astrophysics mount. I don't know why, I guess it's one of those unaccountable things. The thing is that now I have a chance of buying one, specifically the GTO 900. Up till now I have imaged with the EQ6 (which is great, really) so i don't have a lot of experience with highest quality mounts. Every now and then I hear on the forum that the AP mounts are "outdated" and old. What does that mean exactly, and if this is so how can they at all be compared to the newer Paramount and 10Micron mounts?

Not a simple question to answer. Astrophysics mounts (and Paramount too) are what might be called 'pure mechanical' mounts which rely for their performance on high precision machining and assembly. They also require _maintaining_ in such condition if they are to perform at their best. It's the precision machining that you pay the big money for. However, it's a bit like comparing a precision mechanical Swiss Watch with a modern Quartz Crystal (or radio corrected) watch where the latter takes advantage of new technology which is simply absent in the former. The very best mechanical watches can keep reasonably accurate time (by today's standards, and at the expense of ensuring it operates in tip-top condition with perfect gear clearances and so on). The accuracy attained is limited by the constraints of actually having to rely on mechanical accuracy, whereas the electronic watches can keep time even more accurately simply though the use of better technology.

So it is with modern mounts. Those that use absolute encoders (the main source of accuracy improvement) and direct drives ( an additional technology which does away with the mechanical drive entirely), they can get around the accuracy limits of the pure mechanical mount by having the ability to correct the telescope drive rate in real time to incredibly fine tollerances. Of course, such mounts also need to be well built mechanically in order to fully exploit this advantage, and not all that claim to use 'encoders' actually do so - they are advertising headline grabbers merely intended to fool you. You get what you pay for really.

ChrisH

[Jessun]

Hi

My 1600 is the least of my problems and I don't use any of the recent upgrades - encoders, new motors or the newest wifi control box. Simply no need as of yet.

Good luck with your choice!

/Jesper

 

 

[ronin]

Likely it is a case that newer items are used, by choice or necessity. They may have have changed to higher torque motors, the motors may have changed from (Guesswork) 2400 steps per revolution to 3600 steps per revolution, so better potential resolution.

What people consider "outdated" may amount to nothing. HEQ5's were Black now White, people put wanted ads in for the White ones. They look better I suppose but the colour does not make them perform better. However in that sense the Black ones are "outdated".

[Kenza]

I mainly shoot in the field so I would need a lighter mount but with good carrying capacity. At home I have a concrete pier for the mount but the LP is high so I shoot mostly NB. I like the idea that the AP mount can be separated into two lighter pieces.

From what I read in other topics all mounts can be divided into:  gears and worm wheels , belts and worm wheel ( or ALL-BELT like the Avalon), Friction drive and Direct Drive.

As I get it, there is no best type. It all depends on the quality of workmanship. Right?

[ChrisLX200]

7 minutes ago, Kenza said:

I mainly shoot in the field so I would need a lighter mount but with good carrying capacity. At home I have a concrete pier for the mount but the LP is high so I shoot mostly NB. I like the idea that the AP mount can be separated into two lighter pieces.

From what I read in other topics all mounts can be divided into:  gears and worm wheels , belts and worm wheel ( or ALL-BELT like the Avalon), Friction drive and Direct Drive.

As I get it, there is no best type. It all depends on the quality of workmanship. Right?

My 10-Micron GM2000HPS-II also breaks down into two parts, albeit both parts are still quite weighty. There is a best 'type' and I already described it to you.

ChrisH

[andrew s]

19 hours ago, ChrisLX200 said:

Astrophysics mounts (and Paramount too) are what might be called 'pure mechanical' mounts which rely for their performance on high precision machining and assembly

While they are high performance mounts due to precision machining they also use modern computer technology to improve their PEC and pointing performance. They do this via feed forward correction rather than feedback via shaft encoders. Both the Paramount and 10Micron mounts use modeling to improve their pointing. In the end the target is a "star" and while all top quality mounts can give good unguided performance neither  Protrack on the Paramount or the encoders or the modelling on the 10Micron  can compensate for all causes of guiding error and closing the loop by guiding on a star can make good practical sense.

If you want to set up at remote sites then I would suggest the ability to polar align quickly would be a high priority along with portability of the mount and model building might not be such a high priority. 

Regards Andrew

[Kenza]

On 10/30/2016 at 16:16, andrew s said:

While they are high performance mounts due to precision machining they also use modern computer technology to improve their PEC and pointing performance. They do this via feed forward correction rather than feedback via shaft encoders. Both the Paramount and 10Micron mounts use modeling to improve their pointing. In the end the target is a "star" and while all top quality mounts can give good unguided performance neither  Protrack on the Paramount or the encoders or the modelling on the 10Micron  can compensate for all causes of guiding error and closing the loop by guiding on a star can make good practical sense.

If you want to set up at remote sites then I would suggest the ability to polar align quickly would be a high priority along with portability of the mount and model building might not be such a high priority. 

Regards Andrew

Thanks for the info, that's exactly what was troubling me. Why get a mount with encoders if i will set up at remote sites most of the time. The only reason why i still can't decide is the customer support. 10 micron is from europe which is great, i can even take the mount there myself for repair if need be. All the rest (apart from ASA) are US based. i know that customer support is really important. Telescope service is offering an MX at a really great price but i would still need to send it to the states for repair.

[Davey-T]

On 30/10/2016 at 15:16, andrew s said:

If you want to set up at remote sites then I would suggest the ability to polar align quickly would be a high priority along with portability of the mount and model building might not be such a high priority. 

Regards Andrew

I have an iOptron iEQ45 that is very light and can be set up, aligned and imaging in minutes and carries about a 25lb load and a 10Micron that takes a lot longer to set up but produces longer / better subs and carries more weight.

What are you using for imaging weight wise ?

Support availability should be very near the top of your list of priorities.

If you only want a nice new shiney expensive mount, to satisfy a lifelong craving, that works as advertised with local support then 10Micron takes a lot of beating.

My 10Micron GM1000HPS is just about portable

Dave

[CraigT82]

On 29/10/2016 at 19:37, ronin said:

What people consider "outdated" may amount to nothing. HEQ5's were Black now White, people put wanted ads in for the White ones. They look better I suppose but the colour does not make them perform better. However in that sense the Black ones are "outdated".

The early black ones (pre Syntrek) have the older, non-stepper motors and dont have the necessary control board to be used with EQ mod, hence why people tend to avoid them

[Kenza]

1 hour ago, Davey-T said:

I have an iOptron iEQ45 that is very light and can be set up, aligned and imaging in minutes and carries about a 25lb load and a 10Micron that takes a lot longer to set up but produces longer / better subs and carries more weight.

What are you using for imaging weight wise ?

Support availability should be very near the top of your list of priorities.

If you only want a nice new shiney expensive mount, to satisfy a lifelong craving, that works as advertised with local support then 10Micron takes a lot of beating.

My 10Micron GM1000HPS is just about portable

Dave

my imaging gear weighs around 12 kg (refractor, ccd, filter wheel...), but i plan at some point to add a 10" sct or RC. 

What in your opinion would be the best choice for imaging at remote sites?

[Davey-T]

If I'm just popping off somewhere dark I'd just take the iEQ45 but for a few days, ie; star party I take the 10Micron.

Be aware that some mounts that use modelling as opposed to guiding are not best suited to scopes prone to mirror shift.

Dave

[Kenza]

I usually go for a peroid of 3-4 nights anyway so a slightly heavier mount wouldn't be  a problem. 

How long does it take to set up the 10micron in the field?

[Davey-T]

34 minutes ago, Kenza said:

I usually go for a peroid of 3-4 nights anyway so a slightly heavier mount wouldn't be  a problem. 

How long does it take to set up the 10micron in the field?

Depends how long a model you need, not a problem if you've got clear twilight skies, I do 60 /80 points using a 110 / f7 refractor but if it doesn't clear until it's dark I can get away with as few as 30.

Setup tripod and mount add scope and balance, it has a super balancing routine which takes about 10 minutes.

First you have to do a small Polar align model, I do 10 but you can do less, then use the centre a star PA method, check the PA error in the handset and if it's within a few arc sec's that's good enough.

Do a sky model, you need some sort of computer modelling and plate solving to speed it up using SGP or Maxim otherwise you can do it manually without a laptop.

Then you're good to go, can take up to 30 min's

Dave

[1parsec]

You won't wrong with an AP900 GTO.  
I don't think it's right to say AP mounts are outdated.  They have encoders and modelling software and all the other whizz-bang options you see from the other suppliers . 
What they can do is perform very accurately without having to mess about with modelling and all that stuff if you don't want to. 
The 900 will be a huge step up in performance compared to the EQ6.

 

[Kenza]

23 hours ago, 1parsec said:

You won't wrong with an AP900 GTO.  
I don't think it's right to say AP mounts are outdated.  They have encoders and modelling software and all the other whizz-bang options you see from the other suppliers . 
What they can do is perform very accurately without having to mess about with modelling and all that stuff if you don't want to. 
The 900 will be a huge step up in performance compared to the EQ6.

 

I saw in your pics that you own an AP 1200 mount. If you needed to repair it or do any modifications would you have to send it to US or would one of the AP dealers in Europe (TS or Baader Pl.) be able to take care of it? If I go with AP in the end, it would be good to know if technical support is available in Europe.

[1parsec]

On 11/25/2016 at 22:13, Kenza said:

I saw in your pics that you own an AP 1200 mount. If you needed to repair it or do any modifications would you have to send it to US or would one of the AP dealers in Europe (TS or Baader Pl.) be able to take care of it? If I go with AP in the end, it would be good to know if technical support is available in Europe.

I bought my mount new from AP back in 2002.  It's worked faultlessly since then so not sure about the servicing.  I would send it back to AP if ever needed as they can do far more than any distributor could and I'd be sure it was done to factory standard.
It would be worth a call to Baader to see if they would service the mount you're interested in for information and peace of mind.  
Mechanically the AP mounts will 'last forever' and it should easily out last me !!.  
I guess it would be the GTO-controller that would need changing before any thing else and it's good to know AP have been developing the controller continuously over the years and now on version 4 which will still work with mounts a lot older than mine.