Kon

Very nice details on the closeup and it has changed a bit since yesterday.

What a treat with the sunspots yesterday. The enormous sunspots AR3668 and AR3664 from 09/05/24. They were visible with the solar glasses too. Unfortunately, I missed the good seeing due to work. 8" Dob, manual, asi462mc, UV/IR cut filter.

Possibly the best sun spot I have ever seen. I missed the very good seeing due to work but it was still breathtaking. I managed some imaging too. A little preview below.

1 hour ago, JOC said:

FWIW have you tried the scope back to manufacturers configuration, no heavy additional objects, esp. heavy EP's.  I find my goto Dob is esp. prone to not functioning well i.e. slipping if I put anything too heavy at one end of the OTA or the other.

My problem is even without the tube assembly on.. It used to track without problems and it went during an imaging session.  I have ordered a replacement motor which I hope resolves the issue as tightening the clutch and checking it didn't resolve it.

4 hours ago, Pete Presland said:

Nicely captured Kon, Mercury is a tough target and like Venus is better imaged in daylight higher up in the sky. A phase is as good as i have ever managed, but there are some stunning images captured during the day.

It is even harder to find than Venus in daylight unfortunately. 

Thanks. I found it hard locating it at daylight but I will try with the goto next time. Venus is relatively easy for me now to spot at daylight so once I know what to expect it should hopefully be easier.

Scrolling through the images, I also found this nice flaring on the iROSAs. A bit happier with this image so a tighter crop.

International Space Station from this morning (331am) at 89 degrees. It seems that it has got a sun flare and I struggled to get more details out. 12" 300P goto, asi462mc, 2.5x TV powermate, UV/IR cut filter. Manual tracking.

Ptolemaeus/Alphonsus/Arzachel from 17/04/24. Skywatcher 300P Flextube goto,  asi462mm, IR pass 685nm, 2.5x TV powermate.

Sinus Fidei and Montes Alpes from 17/04/24, and Maurolycus from 15/04/24. Skywatcher 300P Flextube goto,  asi462mm, IR pass 685nm, 2.5x TV powermate.

1 hour ago, bosun21 said:

Yes Saturn will be interesting due to the rings positioning. I think all our focus will now be on the surface details of the planet which are difficult to begin with. I really hope you manage to get the tracking problem sorted out. I would be pulling my hair out if it was me.

I ordered the motor, let's see .

1 hour ago, bosun21 said:

Yes I am feeling well again and eager to get back out under the sky again. I may capture some more lunar images but my passion is for the planets themselves and I'm eagerly awaiting on their return. I am particularly looking forward to Mars this apparition. I'll keep busy meantime doing visual, which I also really enjoy.

I prefer the planets too, but I do enjoy the crater close ups. A few more months and we will be out again. Saturn is looking interesting from down under with the rings edge on.

Nice images Ian. I hope you are over the illness and hopefully start imaging again, if this weather ever improves.

22 minutes ago, orion25 said:

Me, too, buddy. I'm waiting on Mars and the razor-thin rings of Saturn

I have seen some Saturn images from Australia and it's rather intriguing. Looking forward to it.

Very nice Reggie. Looking forward to the planetary season to start again.

20 minutes ago, bosun21 said:

Watch the video and disassemble it in stages like he did and check the various sets of securing screws. Good luck.

Done it a couple of times already but I will try again.

6 hours ago, bosun21 said:

Kostas have you checked all the relevant grub screws and Allen screws which position and hold the various plates of the clutch assembly? The video posted earlier in the thread shows these various screws and where they are located. I ask this due to your description that the brass worm gear is turning and it is tensioned against the teeth on the drive plate yet it's not moving the axis. To me it appears that the clutch is slipping and this could be due to the screws mentioned. Tightening the main tensioning nut on top of the assembly will have no effect due to this. I would watch the video and check the screws on yours at each disassembly stage. Good luck 🤞.

Thanks Ian. I will try again tonight with the clutches. I found a replacement motor with encoder etc, new, but I don't want to fork £100 if I am missing something with the clutch etc.

12 hours ago, Cosmic Geoff said:

While I have not examined one of these mounts, I am surprised that the azimuth motor should have developed significant bearing wear. My experience of small motors is that this doesn't happen.  If it has, one might expect that under load it would fail to engage with the gearbox at all.   If it IS a motor fault, getting another might prove troublesome and if you can't definitely identify it as a generic motor you can buy on Ebay or from China, your only other recourse is to buy another subassembly or scrap mount.  Or find a craftsman prepared to fit another bearing bush to your motor.

A useful means of diagnostic where the altitude and azimuth drives (etc) have similar parts is to swap bits over and see if the fault follows the part.   The altitude  and azimuth motor/gearboxes in the Celestron SLT mount are the same (same part number) and I swapped them over while chasing a fault. (It wasn't in the motors).

If you attach tell-tales (bits of paper or magic marker marks) to slow moving parts, you can see if anything is moving (slowly) or not.

Thanks for the suggestions Geoff. I swapped the encoder and gears and the problem persisted. I didn't swap the motor but I noticed that the shaft of the azimuth motor has a lot of play, going back forwards when I press it. The alt one doesn't seem to have it. I also noticed the az makes a squeaky noise (even without gears) whereas the alt is quite, thus why I thought it is the motor. If the PCB has a fault I would expect the motor control to be dead? The wormwheel and brass turn extremely slowly but no transfer of movement to the large disc so the motor is engaging with the gears ok. I checked and tightened for slippage. I am running out of ideas what to check next.

It seems that I need a new motor replacement for my Skywatcher 300P goto.  It is the azimuth and it appears to be the output shaft having quite a bit of play and therefore I have lost tracking. Finding replacements from skywatcher are not easy.  Any ideas if I can source a motor where I can add the current encoder or have you had luck getting motors from skywatcher directly? Or do you know what motors these goto have (voltage and rpm?)  I have not seen anything at FLO. Motor below with the gears etc off.

I looked at both axis motors and it seems the az motor is faulty; no electrical but the output shaft has a lot of play compared to the alt. It seems I need to source a new one.

Marco Campaniello is very talented individual who took my Maurolycus crater capture from 15/04/24, and converted it to a 3d fly over using real moon topological data. Do not ask me the details but do have a look at his youtube video that has more of these conversions with amateur captures.

Any my image for reference that allows to move it in 3d:

http://moon3d.altervista.org/maurolycus_3d/maurolycus.html

Original image:

1 hour ago, dweller25 said:

Yes, if you can track it fast enough - it moves very quickly, but @Kon manages it with a dobsonian…….

https://stargazerslounge.com/topic/418411-first-international-space-station-for-2024-260124/#comment-4453699

 

To be honest I have never seen it through an eyepiece, guilty I know, as my efforts have been on imaging it; my only live view is through the finderscope and you can make the panels. I think @PeterStudzhas seen it through an 8" with manual tracking.

Nice images. The mineral colours subtle and excellent.

Nice one Reggie.

13 hours ago, michael8554 said:

Can you swap with the Alt motor ?

So I swapped the encoder and the problem persists; if it is the correct part (the green chip in this photo). I did not want to mess more with the Alt as it is tracking very well. It seems to be a faulty motor. I will look into sourcing a new one (I have not found anything yet). I might start a new post for a motor 🥲

40 minutes ago, michael8554 said:

Have you tried with a better power supply yet ?

But Geoff mentions that this is a stepper motor.

Skywatcher describe it as a "DC Servo motor".

As I understand it, a DC Servo motor only has a single pulse drive and feedback loop from the encoder, unlike a stepper motor, which has two phased inputs.

Could be wrong.

Although a pulsed signal, you might compare the voltages with a cheap Digital Voltmeter at slew and tracking rates.

Can you swap with the Alt motor ?

Michael

I am not an electronics expert, so looking online it was described as stepper but I could well be wrong.

I thought of swapping the motors around but as my Alt is perfect, do I mess with it? But it will be a good diagnostic.

Yes I changed the power supply, not as fancy as the one you suggested but I will invest on very good one.

A voltmeter would be good. I assume I should have similar power?