AZ GTi help please if possible!

[Mr niall]

Hi all

I was hoping somebody may be able to help me or give me some advice for my AZ Gti (with Skymax 127) if at all possible? This is my second AZ GTi in 12 months and the second time I'm having issues. I haven't ruled out the possibility I'm doing something wrong but I'm struggling to see how I'm so far off using a really intuitive system that people seem to rave about!

Basically I cant get it aligned.

I've tried every alignment method available with broadly similar results - insomuch as every time an alignment is completed the resulting slew takes me some considerable distance (between 5-10 degrees) off target. Also it isn't consistently off, it can be off in any direction so I haven't been able to pin down if its going consistently "too far" or "not high enough" or whatever. I've also used a variety of stars for alignment - Jupiter / Saturn / Altair / Vega / Deneb / Dubhe / Mizar. For example I've used stars near each other like Mizar / Vega / Polaris and stars really far apart like Polaris / Altair / Jupiter, but the results are the same. I should note I have no access to anything from the North East to the South East.

Maddeningly when I manually centre it on a target, it is usually (but not always) able to find that target again no problem. Sometimes it is still miles off re-finding the alignment stars. For example, after setup (using Altair as one of my stars) I sent it to M27 - miles off. Centred it - then tried M29 - miles off - then sent it back to Jupiter which I had previously centred and BANG perfect. Back to M29 - perfect, over to a new star - Vega - miles off.

I've been recreating this for the last few nights and I really don't know what to do next. Basically unless I already know exactly where something is, it is fairly useless. It seems to be tracking ok, but I haven't done an extended test.

For the record

• Mount is levelled and everything is tight.
• Scope is perfectly balanced.
• Scope is mounted the correct way round
• Targets are centred using a 4mm eyepiece so pretty close to perfect at alignment stage.
• Have changed batteries 3 times, even different brands.
• Alignment is completely re-set every time, app is forced closed and reconnected between alignment attempts.
• Time / date / location are correct.
• Auxiliary encoders are off.
• I've updated the firmware twice - once to the AZ/EQ version, then again to the standard (.32) current version.
• The mount doesnt feel slack or wobbly in any direction. The motor does not sound like it is struggling.

For the record I'm definitely aligning using the correct stars (!) and I've read the cloudy nights forum on this subject from one end to the other but I don't have any ideas.

So yeah, can anyone suggest where I am going wrong? Honestly I'm so depressed by the whole experience.

Many thanks.

 

 

[Shimrod]

9 hours ago, Mr niall said:

For the record

• Have changed batteries 3 times, even different brands.

For the record I'm definitely aligning using the correct stars (!) and I've read the cloudy nights forum on this subject from one end to the other but I don't have any ideas.

 

 

I know you've changed the batteries, but I've read quite a few posts on this mount that behaviour with batteries can be a bit strange. There is a discussion in this thread about external battery alternatives. The picture in the  @ScouseSpaceCadet is a particularly neat solution!

[GoldTop57]

An alternative power source is definitely worth exploring. Also when you've got both clutches completely undone do both axes move fairly freely are do they bind or feel tight?

[Mr niall]

40 minutes ago, Shimrod said:

 

I know you've changed the batteries, but I've read quite a few posts on this mount that behaviour with batteries can be a bit strange. There is a discussion in this thread about external battery alternatives. The picture in the  @ScouseSpaceCadet is a particularly neat solution!

Thanks Shimrod, I had wondered about that. But ultimately I came to the conclusion that if that is the problem then it’s a faulty unit. If it doesn’t work using batteries I’m not sure I should be expected to pay at least another £70-100 for a bespoke power supply just to make it do so. And I can’t really afford the gamble anyway to be honest!

Edited August 28, 2021 by Mr niall

[Mr niall]

28 minutes ago, GoldTop57 said:

An alternative power source is definitely worth exploring. Also when you've got both clutches completely undone do both axes move fairly freely are do they bind or feel tight?

On the altitude it moves perfectly, on the azimuth it moves anti-clockwise perfectly but when turning clockwise there is a little bit of what feels like stiction or flex before it starts moving. If I just lean on it it’ll flex a couple of mm then bounce back if I let go. But no resistance.

[ScouseSpaceCadet]

To be fair my first unit what feels like a long time ago now just would not align and was replaced. The second was replaced due to internal tapping while tracking. The third that's over a year old now works great. Inadequate power does cause issues. I had random slews etc until I picked up the Talentcell battery.

Anyway, Niall reading your list you seem to have all bases covered except two specifics.

1. Do you start with the telescope level and pointing north before the alignment process?

2. Before finishing each star alignment do you finish with up and right arrow presses?

Edited August 29, 2021 by ScouseSpaceCadet

[AstroNebulee]

On 28/08/2021 at 00:53, Mr niall said:

Targets are centred using a 4mm eyepiece so pretty close to perfect at alignment stage.

Hi, Do you keep the 4mm ep in when slewing to a new target or swap to a wider field one 

18 minutes ago, ScouseSpaceCadet said:

I had random slews etc until I picked up the Talentcell battery

Deffo a top choice of external battery pack and small lightweight and power your mount absolutely ages, I've one I used before going to an asiair pro, cost £47 from amazon. 

[ScouseSpaceCadet]

I meant to add the below;

Besides the leveling and pointing true north missing from the AZGTI manual, the below is also crucial and missing:

 

Rules for choosing alignment stars:

•  It is recommended that the altitude of the two alignment stars are between 15 and 60 degrees and the deviation in altitude is between 10 and 30 degrees.

•  The azimuth deviation of the two alignment stars can be between 45 and 135 degrees, it is best to be close to 90 degrees.

Edited August 29, 2021 by ScouseSpaceCadet

[Mr niall]

58 minutes ago, ScouseSpaceCadet said:

To be fair my first unit what feels like a long time ago now just would not align and was replaced. The second was replaced due to internal tapping while tracking. The third that's over a year old now works great. Inadequate power does cause issues. I had random slews etc until I picked up the Talentcell battery.

Anyway, Niall reading your list you seem to have all bases covered except two specifics.

1. Do you start with the telescope level and pointing north before the alignment process?

2. Before finishing each star alignment do you finish with up and right arrow presses?

Thanks buddy, yes to both of those 👍

[Mr niall]

42 minutes ago, AstroNebulee said:

Hi, Do you keep the 4mm ep in when slewing to a new target or swap to a wider field one 

Deffo a top choice of external battery pack and small lightweight and power your mount absolutely ages, I've one I used before going to an asiair pro, cost £47 from amazon. 

Thanks buddy - sorry yes I should have said, I am changing to a 40mm plossl after alignment not sticking with the 4mm

But I’m still not sold on the power pack idea, I really don’t think I should have to spend an extra £50 on top of the purchase price just to make it work when it says it should run on batteries! 

Edited August 29, 2021 by Mr niall

[Mr niall]

35 minutes ago, ScouseSpaceCadet said:

I meant to add the below;

Besides the leveling and pointing true north missing from the AZGTI manual, the below is also crucial and missing:

 

Rules for choosing alignment stars:

•  It is recommended that the altitude of the two alignment stars are between 15 and 60 degrees and the deviation in altitude is between 10 and 30 degrees.

•  The azimuth deviation of the two alignment stars can be between 45 and 135 degrees, it is best to be close to 90 degrees.

That’s interesting, I think Mizar / Altair fits pretty well in that range though?

[AstroNebulee]

2 hours ago, Mr niall said:

But I’m still not sold on the power pack idea, I really don’t think I should have to spend an extra £50 on top of the purchase price just to make it work when it says it should run on batteries! 

Hi

Yes I agree with you as to not buying extra equipment when it shouldn't need it. I only bought my power pack as I didn't want to keep buying batteries so never used batteries on mine. It's a real shame you've had to mounts and both are ropey ones it seems.

Have you got a different scope to try on it say a lighter one say, thought I had a Skymax 127 on mine and was ok. 

On mine I also took it apart and regreased it and checked the worm motors. I'm not saying you should do this but afterwards my mount rotated much more freely. Can you contact the vendor that sent you the mount and request a refund or replacement as I've heard of a few people having a couple of ropey ones and the 3rd was ok. It's the luck of the draw with these mounts imo. When they work right they are fantastic. 

[adyj1]

5 hours ago, Mr niall said:

But I’m still not sold on the power pack idea, I really don’t think I should have to spend an extra £50 on top of the purchase price just to make it work when it says it should run on batteries! 

Do you have a 12v DC plug-in transformer with a 5.5mm/2.1mm barrel plug (min. 750mA ouptput)? If you were able to temporarily try the mount with a 12v supply - maybe with a mains extension lead from the house - it would be a good way to establish whether  power is causing you a problem.

 

Edited August 30, 2021 by adyj1
added amperage

[Gfamily]

I find that targets near the zenith are more easily 'missed' than lower targets.  What's your mount like when trying to find targets lower down  ? 

[Mr niall]

8 hours ago, Gfamily said:

I find that targets near the zenith are more easily 'missed' than lower targets.  What's your mount like when trying to find targets lower down  ? 

It’s fairly hit and miss at all altitudes, but I think it is actually even worse at altitude now I think about it…

[Mr niall]

9 hours ago, adyj1 said:

Do you have a 12v DC plug-in transformer with a 5.5mm/2.1mm barrel plug (min. 750mA ouptput)? If you were able to temporarily try the mount with a 12v supply - maybe with a mains extension lead from the house - it would be a good way to establish whether  power is causing you a problem.

 

No I wish I did that would be handy, good idea though thx.

[JeremyS]

16 hours ago, ScouseSpaceCadet said:

I meant to add the below;

Besides the leveling and pointing true north missing from the AZGTI manual, the below is also crucial and missing:

 

Rules for choosing alignment stars:

•  It is recommended that the altitude of the two alignment stars are between 15 and 60 degrees and the deviation in altitude is between 10 and 30 degrees.

•  The azimuth deviation of the two alignment stars can be between 45 and 135 degrees, it is best to be close to 90 degrees.

Thanks for this @ScouseSpaceCadet. Hadn’t seen this advice before. I haven’t had any problems with alignment, but it’s good to know what the best practice is. I use the separate handset, but I presume it applies to that as well as the smartphone app?

 

[ScouseSpaceCadet]

53 minutes ago, JeremyS said:

Thanks for this @ScouseSpaceCadet. Hadn’t seen this advice before. I haven’t had any problems with alignment, but it’s good to know what the best practice is. I use the separate handset, but I presume it applies to that as well as the smartphone app?

 

Jeremy, the above applies to Synscan handsets and the app.

The Synscan manual is full of useful titbits. 😉

[Andrew_B]

1 hour ago, ScouseSpaceCadet said:

Jeremy, the above applies to Synscan handsets and the app.

The Synscan manual is full of useful titbits. 😉

That's got loads of good details. Is there anything similar for the phone/tablet app? I found this manual but it hasn't got enough info to properly troubleshoot the problem I've been having with getting alignment to work. 

[Geoff Lister]

14 hours ago, adyj1 said:

Do you have a 12v DC plug-in transformer with a 5.5mm/2.1mm barrel plug (min. 750mA ouptput)? If you were able to temporarily try the mount with a 12v supply - maybe with a mains extension lead from the house

I have used several different 12V, 1.5 or 2A, plug-top mains supplies with my various Skywatcher and Celestron mounts. These supplies came from old USB powered hubs, desk-top external hard drives, and ones supplied with LED stick-on lighting strips.

Geoff

[ScouseSpaceCadet]

1 hour ago, Andrew_B said:

That's got loads of good details. Is there anything similar for the phone/tablet app? I found this manual but it hasn't got enough info to properly troubleshoot the problem I've been having with getting alignment to work. 

That manual and the one I linked are the only Synscan end user manuals I'm aware of...

Edited August 30, 2021 by ScouseSpaceCadet

[Andrew_B]

1 hour ago, ScouseSpaceCadet said:

That manual and the one I linked are the only Synscan end user manuals I'm aware of...

Thanks anyway. I'll create a separate post on here to see if anyone can help figure out the problem.

[Alan64]

Throughout the online tome, particularly regarding Celestron SE mounts, manufactured by Synta as well, it has repeatedly been said that using "AA" alkaline-type batteries with any go-to mount is going to cause problems.  Just because the manufacturers include that power option doesn't mean that it's ideal, for it's not actually.  Why they include the option is anybody's guess.  And you certainly can't use the rechargeable "AA" type, as those are at a lower voltage, 1.2V vs 1.5V.   

Connecting to the mains is an ideal; as are the svelte, relatively diminutive lithium-ion power-packs, and for a detached experience.  There are also power-tanks, like those used to jump-start automobiles, but those specifically for telescopes rather.  There are bad ones, and good ones, among the power-tanks.  Research for the best one, if you wish to consider that option.

[johninderby]

Should be noted that the AZ-GTi mount only requires about 8v to operate so rechargeable AAs work just fine. I’ve used Duracell Precharge 2700mah AA batteries with zero problems. However if you use a handset with the mount then the handset requires over 11v so rechargeables aren’t recommended. Any of the SW or Celestron alt-az mounts that come with a handset have the same over 11v requirements so no to rechargeable AAs.

[Geoff Lister]

My Skymax and Skyliner mounts have the Synscan handset, and, as mentioned by John, above, need at least +11V. As Alan also mentions, the 8-cell battery holders are a poor way of connecting to the individual cells - 16 contact points of dubious quality. I found the best way to provide portable power, was to use a series pair of 5-cell, 6V, 2600mAh NiMH packs, borrowed from radio-controlled model sailing yachts. These packs are designed to work with the peak demands of servo motors, have spot-welded connections, and are terminated with decent connectors, and, despite my best efforts at sailing, somtimes get a bit wet (no problem with astronomy). I also found a 10-cell battery holder, so, if necessary, can use NiCd or NiMH cells. A 3S LiPo battery will also work, but discharges to 9V at its rated capacity, so not quite so useful; but a buck-boost power converter may well solve that problem.

I measured the current consumption of my mounts:-

It's the auto-slew to the 2nd alignment star, that will use both axes at max rate, and highlight any poor contact resistance.

Geoff