HEQ5 Pro NOT tracking

[Marius]

Hi everyone,

This is my first post on this forum, even though i have been a "lurker" for many years. But this time i just cannot figure out this issue, not can i find any pertinent info anywhere on the net; so, as the title says, my mount is a HEQ5 Pro that i bought some years ago from FLO. I never used it for long-exposure imaging (only for planetary image acquisition), but this year i decided to do that as i first wanted to image the comet Leonard A1 and then the Pleiades (every newbie starts with M45 and so i thought it might be wise to do the same. But to my chagrin, i failed at both of them right from the start... Camera is a Nikon D7200 and the "scope" is a Sigma 200 mm lens. My mount will not track (vertical star trails) even for 1 sec and  at 10 secs images come out very bad. And at times the trails suddenly become horizontal and very long. I am familiarizing myself with NINA and wanted to do their polar alignment routine but of course i can't do that since even at 1 sec i have star trails. Polar alignment using the built-in polar scope seems to be a hit-or-miss as i did manage to decrease the length of star trails (to the ones seen in the images below) by fiddling with the Alt and Az knobs but when i do that Polaris ends up very close to the lower right corner (so i find the polar scope extremely inaccurate). I did attempt to hypertune the mount (Rowan belt, replaced all bearings with high-quality ones and eliminated backlash - lots of nice tutorials on youtube that helped me do that), but to no avail. I also played with Drift compensation, custom tracking rates and such in the Eqmod interface but this did not help either (i eliminated the "paddle" and now just connect the mount directly to the laptop with the proper cable). I am at a complete loss with what i should do and buying another mount is not an option at the moment....

 

The images below are at 1 sec and 10 secs exposure and the 3rd is when also at 10 secs exposure but with the sudden horizontal trailing. Camera was pointing high up in the sky, nearby M45.

If anyone has any suggestions, please share then, you would greatly help a fellow newbie. 😊

[malc-c]

Can you provide people with details of your set up.  You mention NINA, so presumably you are using a computer of some description, EQMOD or GSServer for scope control ? and is the scope connected via an EQDIR cable or are you used ST4 as a means of guide control ?

If using a computer, does the mount track with just the handset connected ?

[M40]

Hello Marius and welcome to the site. Adding to malc-c's post, can you drive the mount from the pc? Does it goto your object?

[Marius]

Indeed, i am connecting my mount to a laptop via a Pegasus Astro Eqdir cable. Camera is a Nikon D7200, also connected to the computer via a Nikon-proprietary cable. The telescope is a Sigma 200mm lens. NINA detects both the camera and mount. Finding objects from the Home position also presumably works, since when searching for a particular object it does take me into its vicinity, but not spot-on (would need to do plate solving for that). Same was true also when i only used the HC. But it was the same, the mount would not track properly (hence why i decided to "hypertune" it). So, i guess my only option, short of buying another, much better-build mount, which i won't be able to do for the foreseeable future, is to replace the electronics?

 

PS. I am not doing any autoguiding, i want to first be able to do at least 30 secs of unguided exposures and familiarize myself further with DSO imaging before adding another layer of complexity.

Edited January 5, 2022 by Marius

[M40]

So we know it goes to somewhere close to your target and we know the drives and power supply are ok. Not mentioning polar alignment yet, goto an object, don't bother checking to see if it has found the object, make a note of the mount position and then just walk away for maybe an hour. Then look at the mount position and see if it has moved. If it has moved, we know it's doing something rather than just sitting there. Let us know. Out of interest, do you have the handset?

[Marius]

12 minutes ago, M40 said:

So we know it goes to somewhere close to your target and we know the drives and power supply are ok. Not mentioning polar alignment yet, goto an object, don't bother checking to see if it has found the object, make a note of the mount position and then just walk away for maybe an hour. Then look at the mount position and see if it has moved. If it has moved, we know it's doing something rather than just sitting there. Let us know. Out of interest, do you have the handset?

The mount does appear to track but at a faulty rate (star trails even at 1 or 5 secs). I did a simulation in Stellarium and the mount never tracks properly (for example: i select a star, i.e. Betelgeuse, the star either goes faster than the cross-hairs (indicating my mount), or the "cross-hairs" go faster than the star. Regardless of whether i adjust the "Drift compensation" slider in EQAscom or click on "Sync". "Drift compensation" only adjusts for how much faster the cross-hairs or the star move apart from one another. Two nights ago in NINA i did notice coordinates kept changing for the mount once after i gave it the command to find M45. Same with M42. So i assumed it does track but not properly?... Power supply was/is ok (plugged into my house mains, so no battery-based power supply). I am painfully new to astrophotography and all this ordeal is very overwhelming.... I started with planetary couple of years ago (and a 200pds newt) and found it much easier and rather satisfying but it left me wanting more so now i really want to get into DSO imaging, but i seems i can't do it even with a lowly dslr camera and a lens. 

[jacko61]

I'm speaking as a Celestron user so not sure if your mount has these options BUT it's not something as simple as having the wrong tracking rate set on the mount (i.e. Lunar/solar instead of sidereal) ?

Graeme

[ollypenrice]

Quite honestly I'd get rid of all the third party software and set up and run the mount via the handset to see it there's a problem inherent to the mount.

Check your input data, so hemisphere, location, time (including DST where applicable) date in US format (month-day-year), tracking rate (sidereal.) See if it works properly like that.

Olly

[Pitch Black Skies]

I don't think your mount is tracking at all. Check the tracking rate in the handsets menu's. Sidereal should be highlighted.

[malc-c]

 

1 hour ago, Marius said:

Indeed, i am connecting my mount to a laptop via a Pegasus Astro Eqdir cable. Camera is a Nikon D7200, also connected to the computer via a Nikon-proprietary cable. The telescope is a Sigma 200mm lens. NINA detects both the camera and mount. Finding objects from the Home position also presumably works, since when searching for a particular object it does take me into its vicinity, but not spot-on (would need to do plate solving for that). Same was true also when i only used the HC. But it was the same, the mount would not track properly (hence why i decided to "hypertune" it). So, i guess my only option, short of buying another, much better-build mount, which i won't be able to do for the foreseeable future, is to replace the electronics?

 

PS. I am not doing any autoguiding, i want to first be able to do at least 30 secs of unguided exposures and familiarize myself further with DSO imaging before adding another layer of complexity.

So the mount doesn't track when the EQDIR cable is removed and the handset used in its place.  The fact the gotos are off as well could suggest that the issue is with the clutches slipping, and the fact the mount has been dismantled and tuned would suggest that the issue is more mechanical than related to the electronics.  Especially as you get the same results when driving the mount from the handset and a laptop using EQMOD.  I believe EQMOD starts tracking at whichever rate is set after a slew by default so doesn't need enabling.  Can't comment on the handset setting as I did away with the handset 10 years ago when I set my HEQ5 up in the observatory. 

Did you have the hypertune done by a company or did you do it yourself ? - if it was "professionally" done then i would be contacting the company who undertook the tuning as a stock HEQ5 should give you round stars with a 30 second exposure when decently polar aligned.

[Marius]

Thanks for answering. I dismantled the mount myself since it would cost me an arm and a leg to send it off-country to somewhere where it could be professionally done and with warranty. Within my own country the only person {a "friend") i knew that could help me with some good advice decided he can't be bothered with my existence anymore so, basically i am left with learning things the hard way. I followed the various videos on youtube, especially those by martins' astrophotography and astrobloke. Seemed easy enough and other youtube commented mentioned their tracking did improve substantially (i assumed unguided). I usually persevere and eventually manage but this issue is something that i cannot figure it out at all; been struggling with it for more than a month. Hence why i decided to finally join this online community, with the thinking that any kind of advice is still in the end good advice. By the way, the "stock" mount never gave me that much tracking, at most 15 seconds at 600 mm focal length and only for the Moon. That was back in January 2019 , a couple of months or so after i first bought it.

[malc-c]

• Remove the cover over the gear train (or belt drive if fitted) and either place a mark on the motor gear, or stick a pointer of some description (cocktail stick) on it.  Un-park the scope and set it to Sidereal tracking.  Does the mark or pointer move?
• If the pointer moves, remove the handset and connect the computer via the EQDIR cable.  Power up and unpark the mount and set EQMOD to sidereal tracking.... does the pointer move ?
• Assuming that in both cases the pointer moves then this confirms the electronics are fine and the issue is mechanical.   With the scope powered off, and the clutches locked firmly can you move the mount in RA by push/pulling the weight bar ?  Is there any fee play?
• Repeat this process with the DEC - is there any free play or backlash ?

Other than that I'm at a loss.

[Marius]

3 hours ago, jacko61 said:

I'm speaking as a Celestron user so not sure if your mount has these options BUT it's not something as simple as having the wrong tracking rate set on the mount (i.e. Lunar/solar instead of sidereal) ?

Graeme

No, not at all. In fact, i actually tried ALL of them, including King rate and other custom values but the size of star trails is negligible. The mount does make those "clicking" sounds that it's supposed to make when tracking an object in the sky. Today i re-checked the polar scope (using a far-away object) and it wasn't off by much. I also loosened the worm set screws, even though they were well-set, no backlash but also no gear binding either. Clear skies tonight so i might give it another try. I ran out of ideas, so other than this, i will have to buy something from somewhere to replace the electronics inside...

[M40]

Can I suggest that if you know it's tracking by following malc-c's suggestions, but not at the right rate etc, do as Olly said and remove all the third party stuff, go back to the hand controller, reset everything back to factory defaults and more or less start again.

I went from a dob to the HEQ5 and had the usual challenges so know where you are coming from. I continually had to correct the mount during tracking and it proved to be my failure to set polar alignment correctly.

Set your home position, do at least a 2 star alignment and give it another go. 

Something else to consider, when you did the belt upgrade, are you sure all the connectors are fitted correctly and in the correct positions? 

 

[malc-c]

5 hours ago, Marius said:

 The mount does make those "clicking" sounds that it's supposed to make when tracking an object in the sky. 

A mount should not be making ticking sounds when tracking.  You get a high frequency noise caused by the pulse width modulation through the stepper motors, but it doesn't tick.

Edited January 5, 2022 by malc-c

[lenscap]

Hi Marius, this seems like a mechanical issue to me. Since you have done a belt mod I assume you have pulleys attached to shafts by grub screws.

Could one or more of the grub screws have loosened a bit over time and now slips or slips intermittently at tracking speed but still grips when the belt "grabs" the pulley at much higher slewing speeds?

[Simon Pepper]

I have a HEQ5 pro and it doesn’t click when tracking at sidereal never has. It does make a light grinding noise when go to though but that is normal always has made that noise. I hope you fix it but wanted to note clicking is not right. Thanks 

[Marius]

Thanks everyone for the answers, much obliged! Regarding the "clicking" sounds: to my ear that's how it sounds and from other videos on youtube it seems normal, but i do have to mention that i have some ear issues due to a past inner ear infection (made worse by some long covid issues) and my hearing is a bit messed-up (not up to standards to to speak). Well, now that i think of it that " high frequency modulation pulses" as Malcom mentioned is perhaps a better fit to the actual sounds.

That being said, i did manage to track 60 seconds at 300 mm focal range (450 effective focal ratio since my Nikon is a APC-S sensor). ISO was 1600. At 120 sec (and quite frequently at 90 sec) the stars become elongated (and although noticeable only at 100 resolution, i found it disappointing nevertheless). Obviously, still a far cry from 5 mins unguided; on cloudynights? some users managed that with modded HEQ5 but they were pro's whereas i am painfully new to the whole game . So, for me it is ok for now. Of course, i will go the guiding route once i familiarize myself properly with everything (it did take me 7 hours to take 120 60 sec exposures due to various user errors. Also had some equipment issues since i was using a 12V 14Ah battery which had to be changed in the middle of the session. Same went for the camera battery.

So, what was different from previous nights? First, i re-calibrated the polar scope during the day. My polar alignment through the polar scope was quite good (around 5 arcmins). Using the polar alignment routine in NINA i took it down to around 30 arcsecs but there was a lot of atmospheric turbulence (Romania is not the best country for imagers and especially not my location, so 'it only' took me about 1 hour to take it down from 5-6 arcmin to around 30 arcsec. Second, my Sigma lens was set on autofocus, i had to switch it to manual. Third, lens was set to stabilization on, should have been off. This was apparently a major issue that i kept ignoring (please don't ask why.... ). Fourth, i loosened the grub screws just enough on either side of the worm carriers but without introducing any backlash, so that might have helped too.

I should also mention that Sidereal vs King rate made no difference (M45 was exactly above me so from what i read it shouldn't have at that altitude). Setting drift compensation to 3 apparently did not seem to improve star elongation at 90 and/or 120 sec either. I will tinker some more, but for now i am satisfied. Perhaps in a month or so i will add another layer of complexity and will acquire the EvoGuide as a guide scope. 

[malc-c]

My observations, and I don't mean any offence here.

I think the electronics are fine.  The initial issues have been a combination of the following:

• You performed the tuning of the mount, and by your own omission have stated that you are not an experienced engineer and as such the mount is way off the expected 5 minute unguided claims made by commercial tuning companies or those with more experience.  It may seem a simple design, but even with higher precision bearings installed it still takes a lot of tweaking to get the optimum gear meshing, and end float of the worm etc.  It would seem the rebuild of the mount hasn't actually made that much of a difference.
• Polar alignment for 5 minute unguided needs to be bang on.  Initially your polar scope was in need of finer calibration.  However, given the design of the polar scope it is not possible (IMO) to get this accuracy, even after it is calibrated to the best of your ability.  Plate solving or similar methods that use cameras attached to the mount would give better polar alignment.

Your attempts to tune the mount better, and recalibrate the polar scope have improved the performance to a degree (ignoring your other camera issues) and you have managed to get some workable results.  Personally I think guiding is the key to any form of astro photography.  It can make a poorly performing mount track tightly and give excellent results