AP1600GTO mount review

[gregbradley]

I bought Raki's AP1600GTO a few months ago and drove to Melbourne from Sydney to pick it up. A great road trip that included the Great Ocean Road and some skiing at Buller.

I have used several mounts. Meade LX90, Vixen Sphinx, Mountain Instruments 250, Takahashi NJP, Paramount ME (Still have that), Software Bisque PMX (sold to Erik) and now AP1600GTO.

The only reason I sold the PMX was I could see the AP RHA scope and heavy imaging train, thermal blankets, dovetail plates, rings were at the ragged edge of its capacity and I would get some really nice guiding but everything had to be perfect. I think it handles loads up to about 30kg perhaps 35kgs but the 40kg rated load is a bit optimistic. Still a nice mount and many very good nights of tracking with refractors showed it to be a beauty. It was something of a reluctant sale as only a few months before I saw the best tracking ever with my then AP140 scope at my dark site using this mount.

The AP1600 is more of a competitor to the Paramount ME. I have both and I like both. The PME'sonly advantage over the basic AP1600 is the home switch. I also like the clutch release knobs of the PME. In all other ways I think the AP1600 is superior. That does not mean the PME is no good. Far from it, its still an amazing mount.

The AP1600GTO had these aspects that appealed to me:

1. AP 's total professionalism and amazing competence and practicality. The super high standards they run at.
2. Everything I have ever had from AP was the absolute best and worked without tinkering and was best in its class.
3. The mount can be retrofitted at home with absolute encoders and home sensor for unguided tracking with no PE for around US$8000 or less.
4. AP states a maximum of 5 arc secs/pixel PE as opposed to SB who rate PME 11 at 7 arc secs.
5. It breaks down into 2 major parts easily for transport.
6. It has a complete set of accessories, dovetail holder etc.
7. Its rugged and durable and has a 105kg rated capacity, which knowing AP is proabably conservative rather than my experience with the PMX which was slightly overstated.
8. I liked the idea of an AP mount with an AP scope.
9. I was disappointed by the very unprofessional and flubby way SB handled the PMX release. Quality control seemed to be lacking although to their credit they made it good and they give quite good customer care.

The mount is heavy but it breaks down into 2 parts via a clever interlocking dovetail system. Its very secure which was something I was concerned about, but looking at it the engineering is such that it would be almost impossible for it to pull apart and detach once connected. Each component is heavyish but manhandleable by an average man. This is clever. Each component would weigh a lot less than a PME 11. PME I think must be less heavy than PME 11 as it is reasonably manhandleable (I think, its been a while since I put it on the pier it stays on, it wasn't that heavy). The PME is perhaps at the ragged edge of portability, the AP1600 is heavy but handleable.

The through the mount cabling system is smart and well designed and plenty of room without crowding.

The altitude adjuster is a very clever unit with a large hand grabbable handle which makes fine tuning very easy and its also easy to turn whereas the PME altitude adjuster is quite hard to turn when its loaded with a scope and gear.

The counterweight shaft is around 50% thicker than the PME and PMX which would mean less flex.

Styling is classic but PME 11 looks very nice and PMX is an attractive mount in its pinky red colouring.

The control chip is also easy to change over to the latest which is a plus. SB mounts would require a new motherboard and would be quite an operation to strip the mount down to replace it.

PMX had a nice set of power outlets and USB hub on the dovetail plate that I used occasionally although the USB is a little sensitive to startup sequence so if it dropped out it was a little extra work to get everything reconnected.

The hand controller is rugged and quite large but easy to use for the AP1600. I also like the joystick unit of the PMX and to a lesser degree the PME's joystick (harder to do fine adjustments). You can easily turn down the slew rate with the controller to make fine framing easier. Quick and easy. Also there is an easy to find stop button so if the mount is about to slew your scope into the pier its easy to hit that and it stops it so no need to only have your cursor over the X symbol on the slew box when using Sky X.

The mount is fully compatible with the SkyX via a free Ascom driver and there is also a more advanced driver system that is a replacement for a lot of Sky X controls. The free driver comes with a timer so I use that to make sure the mount stops at a certain time so no risk of hitting anything.
I find Ray Gralaks programming (author of Pempro) to be a step above mosts and his software is rugged, reliable and it just works. Pempro is one of the first astro programs I have found to be able to use first time without some oddity. It just works and does its job without the need to dive into the manual or try to debug or it won't connect to the scope and mount etc etc.

I am able to use TPoint and construct a Tpoint model more easily than with the PMX as slew limits don't get in the way of a successful slew.

Go to accuracy is as good as PME and PMX which are both excellent.

The clutch system on the AP is much better than both PME and PMX. Its kind of stiff when loose and you tighten it from there. But if stopped it could slip if it had to. No risk of slippage from imbalance. Nice and secure.

The motors sound very powerful and indeed they are the same motors as used on the AP3600 El Capitan mount.

Most importantly is the tracking. My PMX had a replacement worm and when tuned up with a nice TPoint model and accurate polar alignment
routine of TPoint was giving around 1.5 to 1.8 arc secs guiding. Very nice.

Pempro PEC curves help and so does a good Tpoint model with tracking corrections enabled.

PME is also very good. I am not sure what the guide errors are but with a MMOAG it will track the CDK17 10minutes and very round stars at 3 metres. Impressive. I also like the simple turn a knob to release the gears for easy movement and balancing of the scope on the PME. It works really well. I am not sure why SB moved away from this as I rate that as a nice feature. PMX 3 way switch keeps you on your toes. Its good so long as you remember to never unload a camera or try to unload the scope without the 3 way switch set to lock. You could potentially smash a scope or drop a camera if it started to slip from a large imbalance if you did not set it to the locked position. I damaged an RCOS scope on the MI 250 mount that way one time. Not pleasant. It had allen key locking clutches (don't go to a dark site and forget to bring the allen keys - oh wait, I did that once! grrrr a beautiful clear night as well).

The AP1600GTO without PEC was running at less than 3.5 arc secs. I think it was around 3. With PEC and using PHD2 guiding (it gives superior results to Sky X autoguiding) I am often running just under 1 arc sec (lowest seen is .62 for about 5-10minutes then it went to .78!). Typical is around .9 to 1.05 arc seconds. This is the most accurate guiding I have seen from any mount.

PEC was very easy to upload into the mount.

It handles the 43kgs of the Honders easily like it was nothing. The PME handles the 80kgs of the CDK17 and gear also very easily. Both are heavy duty mounts.

I do like the home feature of the PMX and PME. You can get that with the AP and there may be a kit to install that at home. If you install the encoders that comes with a home switch as well. But the AP works from a known park position and it always knows where it is. Computer crashes do not affect this. So you could have a computer fail and restart it up and the mount will still be aligned. Rugged and robust is how I would describe its operation. PME is also pretty rugged and PMX a bit less so as its integration with software meant at first a little bit easy to make drop out (the software that is) and with later versions of the Sky X that is now more stable and reliable.

Price wise a new AP2600GTO is USD$11,000. PME 11 is around $15,000. I can't see the extra $4000 just for a home switch so the AP is much better value for essentially a higher performing mount tracking wise (at least there stated PE levels) with a lighter countershaft, no home installable encoders, also SB is prone to changing mounts specs with no backup or concern to existing purchasers of earlier models and no backwards upgradability. AP does. Its a bit like Fujifilm giving free substantial firmware updates over several years for a model whereas other manufacturers either don't and fix bugs with a new model or only give firmware updates to fix major flaws not real improvements like Fuji gives.

So yes I feel it was a great decision and the mount is exceeding my expectations and I plan on one day installing the encoders to have a mount capable of 10 minute unguided tracking with no PE.

Also access to the genius Roland Christen. I bought the mount 2nd hand, I had a computer crash and I had to switch computers and wasn't sure how to do a fresh startup. He answered personally same day and followed up with several postings as well as another technical staff member. SB also have reasonably good support, not as fast as that but they do answer your questions but it may take a week or two. So AP gets a big tick for customer support.

So yes I highly recommend an AP mount and it is a very well engineered and thought out piece of astro equipment that basically disappears into the background when you are imaging. You can concentrate on the imaging and just depend on the mount to do its job once setup. Exactly what you want and somewhat rare in this astrophotography world where fixing up and modifying gear to make it work is too often the norm.

As the mount is the most important component of the astrophotography setup its well worth considering investing that bit extra to get a reliable fussfree mount that will give many years of round star imaging.

Greg.

[DavidTrap (David)]

Trying to get assistance from SB regarding one of their old mounts was like pulling teeth. APs customer service has always been pleasant - have had a couple of great chats with Christine via email - nothing was too much trouble.

Great review Greg - confirmed many suspicions

DT

[Bassnut (Fred)]

Nice Greg, excellent review. But you know, eventually, youll end up with an Ascension 200HR, output encoders standard etc. itelescope tells me its just the ducks guts. Its only a matter of time.......

[DJT (David)]

Originally Posted by Bassnut

Nice Greg, excellent review. But you know, eventually, youll end up with an Ascension 200HR, output encoders standard etc. itelescope tells me its just the ducks guts. Its only a matter of time.......

Awesome! Greg , first dibs on the AP! 😈

[gregbradley]

Originally Posted by DavidTrap

Trying to get assistance from SB regarding one of their old mounts was like pulling teeth. APs customer service has always been pleasant - have had a couple of great chats with Christine via email - nothing was too much trouble.

Great review Greg - confirmed many suspicions

DT

Thanks David.

Originally Posted by Bassnut

Nice Greg, excellent review. But you know, eventually, youll end up with an Ascension 200HR, output encoders standard etc. itelescope tells me its just the ducks guts. Its only a matter of time.......

Accurate encoders is probably the likely path most high end mounts will be taking in the near future. The Ascension is a very high payload mount. Probably the AP3600 is the competitor for that.

Good to know as I was wondering how a Planewave mount would go. Its their first mount as far as I know. I don't see a need personally for a 124kg mount for $23,500. A bit pricey considering the AP1600 is 100kg capacity for $11,000. But to be fair you'd have to add the encoders so that would be around US$17K+. Planewaves CDK20 and 24 need that little bit more than a PME. AP1600 is listed as being able to handle 20 inch CDKs. But I imagine that is at the limit. I am told the PME cannot. Perhaps PME 11 can?? AP3600 would be the one to chose for the really large scopes in the AP stable. Its conservatively (reliably conservative) 136kgs capacity at least and with the encoders is $26,700. Not exactly the same but close enough.

As you would know its better to overmount your scopes. So 20 inch CDK and above would be best to have either Ascension200HR or AP3600. I am sure both are excellent. I wouldn't have the same confidence in Planewave as I would in AP but I have no basis to doubt their mount is great.

I can see ending up with the encoders option on the AP1600 though. It would be cool to be able to do a genuine 10 minute unguided round star image at 3 metres focal length.

The PME is an older mount but its a classic and it still holds up well after all these years.

Greg.

[Slawomir (Suavi)]

Great review, thank you Greg for taking time to write it up and for sharing your experiences with various mounts.

[gregbradley]

Originally Posted by Slawomir

Great review, thank you Greg for taking time to write it up and for sharing your experiences with various mounts.

You're welcome Slawomir.

Greg.

[ramv (United States)]

Very nice review Greg! AP makes great stuff. Even their older stuff is quite nice.

I am using an older AP900 with my TEC ADL300 and other scopes. The whole system weighs nearly 30kg which is almost at the limit of the mount capacity.
Despite this, I recently got 0.47 arc secs RMS total with phD2 on a night of excellent seeing. The FWHM for my entire luminance stack was 1.8 arc secs with the ADL.

[Peter Ward]

For correctness, the AP1600 lists at $US11700, which does not include a saddle plate or counterweights. Theses will add a nominal $US1000 to the price, hence about $US2300 less than a PMEII

Must admit, I looked long and hard at migrating from my PME to an AP1600,
but in the end stayed with Bisque due their superb software integration, and the ability to seamlessly match the tracking rate to any object including low earth satellites with a single mouse click.

But as you stated, both are excellent products and will deliver years of superb service.

[dvj (John)]

Nice one Greg. I've use a 1200 goto for years in my home observatory (supports my Honders), and have 2, PME's in Oz. The big difference between the 2 mounts is the meridian crossing. The last gen of PME leaves very little room for meridian crossing, whereas the AP 1200 can go quite a few hours across, so I rarely need the dreaded mount flip. The new PME II has addressed the meridian crossing issue.

I think the PME is an excellent mount, but being forced to only use TheSky software is a worry. The recent Daily Build update for our SkyX, killed some features. That's always a problem when something mechanical is so software centric.

- jg

[gregbradley]

Yes imaging past the meridian is very handy. If the object is slightly north or south you can image for hours past the meridian. I did that the last few imaging sessions. It enabled 6 hours of data collection without any meridian flip with superb tracking. Very productive. PMX does that as well up to 2.5 hours past the meridian. The AP can go further than that. I believe it will do a full 360 if it doesn't hit anything.
Last night I had it leaning to the east quite a long ways, perhaps 2.5 hours before the meridian plus around another 3.5 to 4.5 hours on the other side so it may have even been 65 to 7 hours. That's about maximum you can image in a night on an object and really makes it easier to do long integration times. 2 nights like that is over 12-14 hours of data. That's really taking advantage of a clear night.

Peter, yes you do have to add the dovetail (about US$320 and a beautiful dovetail it is too, 3 knobs, a section of dovetail moves in as opposed to only a brass point which can crush your dovetail plate if over tightened in SB and weights costs are similar to SB). As far as seamless with software I find the AP1600 is very seamless with Sky X. I was able to upload the PEC curve more easily than for PMX and all the Sky X features like TPoint and Protrack work fine. I found it bypassed the SkyX bug on slew limits which seem very hard to set correctly and easy to get error message out of limit slew errors that are clearly not right, which leads to maybe 85% success rate on TPoint points as opposed to 100% with the AP. The main features SB mounts give are the Sky X Bisque TCS which really only is the software slew limits and the exercise the mount, plus the southern/northern hemisphere (also tends to be buggy and can flip to northern even though it states southern hemisphere). Tracking rates are also able to be changed easily on the AP. The AP does variable rates depending on position in the sky.

There is also an AP more advanced software control system which you buy. Although for me SkyX is sufficient. You can also tune the tracking rates with the AP software if you wanted to.

Greg.

[Peter Ward]

Originally Posted by gregbradley

..You can also tune the tracking rates with the AP software if you wanted to.....

Greg.

That's interesting, so if you right click on a Comet/Asteroid with SkyX, can you set that tracking rate with the AP to follow it in RA and Dec?

I'd be surprised if that was the case....but very cool if it is.

While the PMEII will go three hours past the Meridian, I am impressed the AP is not really limited in that respect.

[TR (Terry)]

AP mounts just work. They are designed well, and have great customer support. The Software Bisque crowd can be quite condescending towards their customers the support forums (my experience on a few queries). Astro-Physics has excelled in this department.

The AP mounts are fantastic for us mobile imagers. When you arrive on-site it's like building a big Lego toy. Just stack the blocks up and you are left with a fantastic imaging platform.

Terry

[DJT (David)]

Originally Posted by TR

AP mounts just work. They are designed well, and have great customer support. The Software Bisque crowd can be quite condescending towards their customers the support forums (my experience on a few queries). Astro-Physics has excelled in this department.

The AP mounts are fantastic for us mobile imagers. When you arrive on-site it's like building a big Lego toy. Just stack the blocks up and you are left with a fantastic imaging platform.

Terry

+1 on the service from AP
Taking mine out to the dark site this weekend for the first time and it will go on a Berlebach Planet tripod. Slight trepidation about stripping down and putting it back up as its spent its life so far on a pier so good to hear the lego comparison.

Greg, great write up. I didn't do the effort you put into your review any justice with my last tongue in cheek comment so apologies for that.

[Logieberra (Logan)]

Greg, a wonderful writeup. I look forward to reading about your experiences in installing the encoders, and using APCC, if I could tempt you there

Cheers, Logan.

[niharika]

Originally Posted by Peter Ward

That's interesting, so if you right click on a Comet/Asteroid with SkyX, can you set that tracking rate with the AP to follow it in RA and Dec?

I'd be surprised if that was the case....but very cool if it is.

While the PMEII will go three hours past the Meridian, I am impressed the AP is not really limited in that respect.

probably not as easy as right clicking. But RA & DEC rate can be specified manually.

And if the user has APCC it can be automated further with horizon
https://www.youtube.com/watch?v=oidwWlVRBVs

[gregbradley]

Originally Posted by Peter Ward

That's interesting, so if you right click on a Comet/Asteroid with SkyX, can you set that tracking rate with the AP to follow it in RA and Dec?

I'd be surprised if that was the case....but very cool if it is.

While the PMEII will go three hours past the Meridian, I am impressed the AP is not really limited in that respect.

I am not really sure Peter if you can click on an object in the Sky X like that. Perhaps, perhaps not. I'd have to try it out.

But the AP manual is full of detail about changing the tracking rates and it will track on other objects. Its a pretty comprehensive keypad which is quite simply laid out. I haven't needed to do that so haven't checked it out further beyond noting the interesting features.

There would be a point where going past the meridian is not worth it and 3 hours is plenty, after all that is 45 degrees from vertical. I often don't image below or past that very often anyway.

Greg.

[g__day (Matthew)]

Pictures? Great review! A bit off topic but does the SkyX allow one step tracking of satellite and comets for all mounts whose controllers support variable RA/ Dec rates to track objects? I know my aging Skysensor2000-PC does that (even if significantly polar mis-aligned). I love it when I occasionally read the high end mounts have features that the SS2K + Atlux had 20 years earlier (but of course no way near as polished, and I can only dream of your absolute position sensors and all sky / near sub sec pointing and tracking ability and carrying capability...

Wonder if I will ever win the lottery!

[gregbradley]

Originally Posted by g__day

Pictures? Great review! A bit off topic but does the SkyX allow one step tracking of satellite and comets for all mounts whose controllers support variable RA/ Dec rates to track objects? I know my aging Skysensor2000-PC does that (even if significantly polar mis-aligned). I love it when I occasionally read the high end mounts have features that the SS2K + Atlux had 20 years earlier (but of course no way near as polished, and I can only dream of your absolute position sensors and all sky / near sub sec pointing and tracking ability and carrying capability...

Wonder if I will ever win the lottery!

Here you go:

http://www.pbase.com/gregbradley/image/161014757

Greg.

[Slawomir (Suavi)]

Beautiful equipment and some solid weights hanging off the focusers!

That is a truly wonderful office Greg, maybe you just need to add some flowers...