NEQ6 Alignment Failed

[JohnSadlerAstro]

Hi,

On Monday night, about 9pm,  I set up the NEQ6 (SynScan V 3.25) for a session on Makarian's chain. Unfortunately it didnt go well, as after 4 attempts I could get the mount star aligned. I was tired so gave up in frustration. ?

My "workflow" is roughly as follows:

1. Setup

2. Rough Polar Align with Polescope

3. Preliminary 3-Star & Focus (normally on final star)

4. PHD Drift Align

5. Return to home, Re-Align

6. Slew to Target, start Guiding

I just could not get past step 3. The first star was quite a way off (as it almost always is, there doesn't seem to be a way to accurately reset to home position) the second one was within the fov, and the 3rd one was about 1/4 off centre. Every time it would give the message "Alignment Failed" ?

If I remember right ?, the stars were:

1. Arcturus

2. Dubhe

3. Betelgeuse

I believe I also used Regulus as my 2nd star on 2 of the attempts.

I am 100% sure that I had the date in the weird ?? format and that the time was correct to within a couple of minutes. Lat Long was left unchanged from my previous session. Is there something wrong with my mount? ? This hasn't happened before, only once when I polar aligned it so badly that even an alt az mount would blush!

John

[Hallingskies]

John:  I have found that for imaging purposes, a one star alignment on a bright star near my intended target works best.  Once aligned, slewing to the target then gets me “on chip” most times.  I use EQMOD now, but I recall that I often could not get the handset to accept alignments unless I used the reference stars it volunteered.

If you have to set up fresh each time, a QHY Polemaster might be a good investment.

I think your time needs to be more accurate than “a couple of minutes” as well. Depending on where you’re aiming, two minutes could be 30 arcsecs or more?

[Wiu-Wiu]

I have encountered the same problem; here's what I learned: 

- make sure the mount is as LEVEL as possible. 

- Date and time are REALLY important. (I have never been able to wrap my head around the whole daylight savings time setting)

- The zero position varies all the time (because you eyeball it, admit it ) so your starting point will always differ; don't expect the mount to be spot on every time.

- Polar alignment errors make the goto error bigger. 

- The error isn't taken away by aligning to the three stars, it seems like it's just a way of telling the mount how wrong it is set up. 

 

What I do now: 

- Level the mount

- polar align as well as I possibly can.

- Slew to a star from my 'zero' position (it is important to tell your mount where the starting position is, but that could as well be due east as a matter of speaking.)

- instead of correcting with my handset, I MANUALLY put the first star in the center, by unlocking the RA and DEC and fixing them when in position. 

- 2nd and third star align will be much better. I do correct those with the handset though. 

 

I have pretty good goto results with this; but after a few hours of slewing, the error (there still is one due to imperfections) is getting so big my targets are off center, and I just redo the whole process. this time with the handset only. 

[newbie alert]

First of all the accuracy  of your star alignment relies on a few factors..mainly how well you center the stars..mearly putting it in the center (ish) of a eyepeice or on a DSLR screen isn't quite good enough..use a cross haired ep or as i do now  use my capture software with the cross hairs..

Another important thing is cone error, I hibernate the mount and wake up to save time doing the star alignment every time I setup, and found my targets were ok one side of the meridian but way off on the other side..So I spent a evening adjusting out the cone error on my scope( shocked at how much there was)

Even thou it's not perfect, it's far better than it was and my star alignment is far better than before..

I don't agree with the connection between star and polar alignment(2 different things) and entering by releasing the clutches defies logic, I'm sure it has no idea where it is then..

Also if you drift align then return to home and adjust in any way you are knocking your star alignment out and your drift alignment too..

I'd polar align, then star align..job done

[JohnSadlerAstro]

Hi,

Thanks for all the advice folks. I'm out testing at the minute; I realised I was confusing Denebola and Regulus for starters, that probably didnt help. Cone error may well be playing a part as well, I want to research that further and see if its possible to eliminate that on a setup-each-night system. ? Checking on APT it looks like I can quite easily get the reticule to appear for hyper-accurate alignment. Thankfully my wide fov is quite tolerant!  

I'm currently running alignments and there seems to be no issue -- using a 1 star align and hopping over to a nearby target seems to work really well. Ive calibrated the polescope, so hopefully there is now 0 chance of that affecting the alignment. As an added bonus, that should also remove the need to drift align in future and do the second alignment (all told about 30-45 mins cut off setup time). 

@Hallingskies this sounds really dumb to ask, but the handset will run like a clock once ive put the time in, right? So I if I set it exact at the beginning of the alignment it will hold the correct time throughout the session? 

I guess this is all part of switching to goto! Still easier than a mount that couldn't guide whatsoever though.....

Thanks!

John

[Hallingskies]

1 hour ago, JohnSadlerAstro said:

 

@Hallingskies this sounds really dumb to ask, but the handset will run like a clock once ive put the time in, right? So I if I set it exact at the beginning of the alignment it will hold the correct time throughout the session? 

I guess this is all part of switching to goto! Still easier than a mount that couldn't guide whatsoever though.....

Thanks!

John

 

[Hallingskies]

There are no dumb questions.  You’re on the same learning curve as everybody  else!  

Yes, the handset time once entered is good until turned off.  Shame it won’t remember it, though I think there’s a GPS add-on that can put it in for you, but sticking in a time is no real problem.

Would recommend using EQMOD with the NEQ6.  There’s a really good FLO blog post (15 June 2015) on how to get going with it.  It takes the handset out of the loop, lets you pick alignment stars (and targets) from a planetarium programme and also lets the PC directly guide the mount via PHD. And it uses the PC clock time (best set that to UTC to save the headache with BST though!).

I am a complete numpty when it comes to computers and yet even I managed to get it all to work.  It’s that easy.

[spillage]

If you are using APT then forget about star alignment. Just set up and run pointsolve. You will never look back. Get yourself an eqdir lead and let your handset collect dust for the rest of its life...

[bottletopburly]

+1 john for spillage advice , get pointcraft setup it’s definitely worth the effort , I use my qhy5l-11 in a qhy miniguide scope  and use sharpcap polar align to PA ,other use a finder guider with good results , Eqmod definitely the way to go if you can ,  never used the handset ever .

[JohnSadlerAstro]

Hi,

I'll switch to EQmod as soon as I can!  

Would this cable be suitable? https://www.firstlightoptics.com/sky-watcher-mount-accessories/sky-watcher-synscan-usb-to-serial-rs-232-cable.html

I've heard that some cheap usb - rs232 cables cant be used for control, I assume this only applies to the ebay sort! The Lynx Astro ones seem rather expensive for a simple cable....  

One other question, do I have to have the paid for version of APT to be able to platesolve etc?

John

[spillage]

better off with this one  as it is eqdir so is not dependent on using the same usb slot every time you use it. (sorry I meant it has FTDI chip)

 

The free version of APT will be fine.

[George Gearless]

Not sure if this is relevant now, but a couple of weeks ago I had almost the exact same problem as you. 

I never quite figured out a solution. On a hunch, or perhaps because it was the only thing I hadn't tried, I reset the handset to factory settings. I usually use 2-star align. The first star was quite a bit off. Not even in FOV. Probably because my starting point was only approximatet manually to start position. The second star was only juuuust off center and required only minimal adjustments. No matter what I threw at it that night, it was spot on every single time. To this day, I have no idea what went wrong in the first place. 

My mount is a EQM-35 pro. But I presume the handset and the alignment procedures are the same for both our mounts.

If you're all sorted, then disregard.

[carastro]

I have had similar problems in the past, though I never drift aligned.  Tried it once, and found it so much faff, and didn't have good enough horizons, so never bothered since.

I think you have probably ironed out some of your problems, but would just like to mention that it took me some years to work out why I could not find some of my alignment stars, until I finally realised I had cone error.  Not being clever enough to risk trying to sort out the cone error (knowing me I am bound to make things worse not better), I now just do a one star alignment close to my target (even with the handset), and it works so much better.   If I have to do a Meridian flip, I just go back to park, and do a new alignment on the other side of the Meridian.  

Yes being more accurate with the time will help, as would Polemaster or something similar.

I do use EQMod from time to time, when I have enough USB ports available, that does give you a better choice of alignment stars, and other options too.   

HTH

Carole 

[JohnSadlerAstro]

Hi,

Thank you for the advice, I really appreciate it, goto is quite a learning curve! The use of a 1-star seems to make the setup process a lot easier, and it removes the time wastage of trying to work out what all the strange star names are! My setup location is more or less limited to just the east and south anyway, so it can be difficult to get 3 stars if I don't choose the first one wisely! (resisting the temptation to make Sirius my 1st star, etc )

Cone error is something I have heard of but don't really want to tackle right now! Hopefully 1 star alignment will prevent it from becoming a big issue.

I have been very bad and manually rotated and locked down the setting circles after parking my scope the other night, so that "home" is 90 dec and 12h ra. Hopefully I can now replicate the "home" position to within a degree or so. Getting the 1st star within the field of view would be very nice, as the finderscope shoe is being used by the guidescope and I have to use a wobbly red-dot strapped on the side. I never use the setting circles anyway, as the handset gives a digital read-out.

John

[spillage]

If you go down the eqmod route then home is just where you star off from. Weights pointing down and scope at 90. I have used a marker pen so if I do unlock the clutches and move it I just need to roughly put it back where it should be and pointcraft will sort the rest out.

[Anthonyexmouth]

The first time you use plate solving instead of star alignment do yourself a favour and wear lots and lots of padded clothes. you'll spend the rest of the night kicking yourself. 

[kirkster501]

Eqmod has a superb polar alignment routine.  To be ‘roughly’ polar aligned is not good enough.  This need to be the first thing you do after set up.  Then from home position slew to,your first star and platesolve. You will never look back.

[ollypenrice]

If a properly aligned polarscope is not getting you to within tolerance for 10 minute subs then your problem lies elsewhere.

Olly

[JohnSadlerAstro]

Hi,

The weather is rather bad here at the moment, so I'm waiting for a clear night to check that the polarscope gives the required accuracy for autoguiding. (I'm expecting that it will be good enough, though.) 

Meanwhile, I'll be saving for the EQMod cable!  

One feature ive heard people mention is PAE, am I correct that this allows fine-tuning the alignment without having to re-do the align?

John

[RolandKol]

12 minutes ago, JohnSadlerAstro said:

Hi,

The weather is rather bad here at the moment, so I'm waiting for a clear night to check that the polarscope gives the required accuracy for autoguiding. (I'm expecting that it will be good enough, though.) 

Meanwhile, I'll be saving for the EQMod cable!  

One feature ive heard people mention is PAE, am I correct that this allows fine-tuning the alignment without having to re-do the align?

John

PAE - is a handset option, stands for "Pointing Accuracy Enhancement", it is actually "mapping" the sky for a better targeting. Takes time to "map", but once mount moved from it's original place, - all lost... Not very effective.

EQMOD and plate-solving is thousand times more reliable, faster and easy to repeat.

If mount missed your star/target, do 5sec exposure, plate-solve (around 30sec) and you are dead center on it, and think of meridian flips, - software will be able automatically to re-target dead center on the target without any involvement of yours.

Any cone errors will have no effect. You Simply watch how your mount flips and recenters while drinking coffee... Or sleep, - your choice