And here are the Masters:

10s and 30s

masterLight_BIN-1_EXPOSURE-10.00s_FILTER-NoFilter_RGB.xisf masterLight_BIN-1_EXPOSURE-30.00s_FILTER-NoFilter_RGB.xisf

Two nights ago, after fixing my mount, and achieving steady guiding, I attempted M42.

Scope is 350FL, 70mm refractor, ASI294MC Pro, Guiding, and used the Optolong UV/IR filter.

I took 10s, 30s and 60 second subs.

I also took corresponding darks at same temperature (-5C) and Flats and dark flats at the end of the night.

The flats are clean, and I checked them, no artefacts.

The resulting masters have terrible artefacts, and I cannot find the culprit?

I stacked the subs in WBPP, and ALL the three masters had the same artefacts.

I also tried stacking just the 30s subs alone WITHOUT ANY CALIBRATION files, and the artefacts are there.

Would appreciate if someone can advise as to why this artefacts are showing up?

Attached are the Masters as well as subs from each stack, in case anyone has the time to have a look.

Many thanks

masterDark_BIN-1_EXPOSURE-4.82s.xisf masterDark_BIN-1_EXPOSURE-10.00s.xisf masterDark_BIN-1_EXPOSURE-30.00s.xisf masterFlat_BIN-1_FILTER-NoFilter_CFA.xisf 2022-02-15_21-07-45__-4.90_30.00s_0006.fits 2022-02-15_23-18-35__-4.90_10.00s_0016.fits 2022-02-15_23-11-16__-4.90_60.00s_0002.fits

4 minutes ago, Same old newbie alert said:

Did you buy the 120?  Standard or EC?

The 120EC version. Fingers crossed!

33 minutes ago, RafalT73 said:

Hi, as I am waiting for my new CEM70EC I  am very interested in yours experience with CEM120EC especially in terms of reliability of encoders. Have your concerns about the operation of the encoders come true? Are you satisfied?

I will certainly update here when I get to use it.

It's still in the box! I plan to open it and start using it when the obsy is ready.

I thought I would update this thread with my findings, just in case someone else needs replacing the bearings on their AZ-Eq6 Pro mount. 
 

Thr bearings used by Skywatcher are: 

JESA W5 608Z

22mm diameter 

8mm bore hole

7mm thick

”Z” seems to stand for SEALED bearings with the metal plate. 
 

I could not find any SKF bearings in the local market, and I used Japanese NSK bearings. 
 

They did the job. 
 

For reference the bearings needed are:

SKF 608-2Z ( think the 608-ZZ is the same)

or

NSK 608 Z

Also, just a work of caution. The worm shaft CANNOT be pulled out of the RA worm carrier with the mount assembled. There is a plastic plate on the shaft that is sandwiched by a sensor which makes up the secondary encoder. 
 

A full disassembly of the mount is required.  

The mount is currently abroad. 
 

The only model I can find in the local market is:

SKF 608-ZZ

Is that similar to the 608-2Z?

There also seems to be a SECONDARY encoder housing on the shaft, so it seems the worm shaft cannot be removed while the mount is assembled. It seems that I need to strip the mount again and access the RA carrier and housing from inside. 
 

1 hour ago, Jonny_H said:

Yes, on mine the shaft narrows down to 8mm where it passes through the bearing. I assume yours will be the same.

Perfect. I’ll order two bearings. 
 

Can you please advise how to actually remove the shaft and bearings?

3 hours ago, markse68 said:

you need to pull the bearing off the shaft- it won’t be 14mm where it goes through the bearing- it’ll narrow down I think- probably the diameter of where it passes through the pulley in your photo

Mark

Thank you for your reply.

Can you please advise how to pull the shaft out of the bearings? The pulley has two grub screws on the shaft, but removing those did not make a difference?

How can I dismantle this part?

Many thanks

1 hour ago, Jonny_H said:

Yes I believe the bearings are the same as mentioned in the previous post above. FYI I purchased mine from Acorn Industrial (part numbers below) for my AZ EQ6 GT.

ACORN CODE	608-2Z-SKF
HS CODE	8482 10 90 30
COO	IT

Many thanks for your reply.

Is it this one?

https://www.acorn-ind.co.uk/p/skf/single-row-deep-groove-ball-bearings/608-2z/c2egjn-skf/

The inner diameter is 8mm and outer diameter is 22mm

The outer diameter fits with my measurements, but the inner diameter is 8mm?

I measured the shaft at 14mm?

Does the shaft narrow down to 8mm inside the bearing?

Many thanks

I’d appreciate it if someone can supply the model numbers for these bearings?

I measured the worm shaft at 14mm (this would be the inner diameter of the opening in the bearing) and the external diameter of the bearing at 22mm

I cannot find any bearings on SKF website that has those dimensions?

Are those two bearings these by any chance?

https://www.tme.eu/en/details/skf607-2z_c3/roller-bearings/skf/607-2z-c3-skf/

607-2Z/C3 SKF  SKF

On 15/08/2018 at 14:11, mikeobrien said:

Worm gear bearings are SKF608 2RSH or you can use SKF 608 2Z which has metal dust covers, If you are in the UK you can order these from Simply Bearings.

 Simply Bearings Ltd
Halton House
Greenfold Way
Leigh
Greater Manchester
WN7 3XJ

01942 269837

On 15/08/2018 at 22:43, Jonk said:

Thanks Mike, I'll take a look.

 Very sorry to resurrect this thread. 
 

I need to replace the bearings on my RA worm shaft of the AZ-EQ6 Pro

Are these the ones described above?

Yesterday I noticed that there is a very fine and subtle vibration in my scope when my AZ-EQ6 Pro was slewing in RA. 

I had already been struggling with guiding for the last week, and my RA would go up to 7rms for no obvious reason. 
 

I used to have constant 0.5-0.7rms, and over the past month or so the RA had been terrible. 
 

I stripped the mount today, and I seem to have found a problem. The worm shaft is VERY rough when I turn it by hand and NOISY. 

It seems the bearings are gone. Mount is just 2 years old. 

The same one on the DEC is silent and buttery smooth  

Any idea what I should do? Grease? WD40?

Is this replaceable or serviceable?

Many thanks

Agree with all the above points. 
 

I think the advice regarding the HEQ5 as a minimum starting point for AP relates to the previous experiences of all those that actually gave that advice. 
 

Almost everyone who bought some sort of star tracker to start out, found themselves upgrading to a proper mount to go deeper and longer. 
 

I suppose the advice is solid. 
 

And as the saying goes: I’m not rich to buy cheap!  Buy once, cry once. 
 

Well done!

Fantastic first results!

2 hours ago, johninderby said:

Same factory that builds many of the TS refractors, Technosky and many of FLOs. All built to the same quality but the various resellers add different accessories. 

The quality of this new crop of scopes is really very, very impressive.

I can only vouch for my Altair Starwave 70EDQ-R 4 element Apo. I have a WO Star 71 5 element apo and an Esprit 100. The fit and finish, especially on the focuser is excellent, even compared to the Esprit. The focuser and rotator are buttery smooth, and the paint job is top notch, even though that's just cosmetic.

5 hours ago, Chris Willocks said:

So I've finally received the scope I must say it's a beaut; quite a bit bigger than I thought in real life, but they always are. Makes the FSQ-85 look tiny:

The focuser is pretty large as well. Should be good for imaging:

I like the fact that they include the optical report. Strehl ratio is 0.980, which I presume is quite good?

Anyway, just installed it in the dome with the FSQ piggybacked. Hopefully I can get imaging with it soon, when the weather picks up.

Chris

Congrats on the new scope. 
 

I’ve always felt that Altair’s scopes are a level up in quality of build compared to the rest of the mass produced scopes on the market. Especially their focusers and rotators. 
 

Always wondered who makes their scopes?

4 hours ago, wimvb said:

It seems to me that you need to make an offering to the astro gods. (Or buy a quality saddle from FLO.) I wouldn’t rely on just one bolt either, and if the saddle thread is stripped, replacing the bolt won’t help. I know that most astronomy dealers have saddles. Just make sure that it fits your mount. Btw, does your Esprit have a vixen or a losmandy dovetail bar? For a larger scope, a Losmandy seems more stable. On my 190MN I have replaced the standard vixen for a Losmandy

Hi Wim

Yes, I contacted FLO today. They do not have the ADM saddle in stock. The problem is, I am abroad!

I could not resist. I used the second bolt, and it give an OK grasp, but week. I zip tied the heck of the Esprit and its rings and clamps to the saddle, just for reassurance!

I am having a NIGHTMARE now with guiding.

Ran calibration. It was not happy! Says I have SEVERE DEC backlash.

This is confusing. If I have SEVERE DEC baclash, why is my DEC RMS 0.09 in PHD2, and the RA is almost 3.5RMS??!!

So, it seems RA issues continue.

I am now running Guiding Assistant, and will post results.

I am very confused about PHD2's interpratation.

BTW, I fine tuned the grub screws, and both DEC and RA are SOLID. No play at all? Why is there still significant backlash?

In the current setup, I am using the Esprit, with a 290MM Mini fitted to the 9x50 Skywatcher guidescope, at 181mm focal length.

Just before all of these issues started, I was regularly guiding with a TOTAL RMS of about 0.7RMS, but that was with the WO Star 71 fitted with the Sky Watcher Evoguide 50mmED and the smaller 120MM Mini.

I think I have grown a few years older this past week!!

1 hour ago, wimvb said:

If the mount slews to any target and tracks that target, then there is nothing mechanically wrong, and any issue is in software. I am not that familiar with eqmod, but I know that you can have several options to set park position. As regarding pointing model, I assumed that this is similar to the eqmod driver in INDI. But you may want to check this.

Perfect.

Yes, I missed the tickbox for DISABLE ENCODERS. Once I unticked that, everything went well.

Many thanks

P.S. It seems my the GODS will never allow me to take this out for a night of imaging!!

I loaded the Esprit and imaging train on the freshyly assembled mount. As I was tightening the two knobs on the VERY poor stock saddle, one of the knobs gave way, and would simply not tighten!!

Why is EVERYTHING going wrong for me...?

Anyways, I am very worried of leaving the Esprit on the mount with just ONE knob tightened. It seems the inner threads of the saddle stripped!!!

Are they M10 bolts?

4 hours ago, scotty38 said:

Ok I was just wondering if the encoders were connected up ok or even not been damaged. I don't actually know what effect that would have but was thinking they'd have "knowledge" of where the mount is and could be involved with parking versus the motors just slewing as it were....

2 hours ago, david_taurus83 said:

In EQMod disable the encoders and make sure the limits are unticked. See if that solves it. The encoders are no real use if using EQmod and only cause conflicts.

Perfect.

Yes, I missed the tickbox for DISABLE ENCODERS. Once I unticked that, everything went well.

Many thanks

44 minutes ago, scotty38 said:

I'm not being funny but have you checked the obvious and made sure you put/connected it all back together as it should be?

Yes, absolutely.

The mount slews perfectly, and its smooth and there are no issues with slewing.

It just does not park in RA?

I am confident it's a software setting that is the issue?

Logically it cant be a mechanical issue, otherwise the mount would not be responding to slew commands in RA?

55 minutes ago, wimvb said:

Just turn the encoders off. They are only needed if you intend to manually move the mount after you’ve done a star alignment. If you use eqmod, you don’t do that anyway. Also reset any mount model in eqmod. What you do want to test now is guiding.

You also don’t need the auxilary encoder on RA. This is only used if you use the mount’s PPEC. And PPEC is incompatible with guiding.

Thanks WIM. I have turned off all the encoders, but the mount does not respond at all in RA to the Park command. Both in NINA and EQMOD.

Say I manually put the mount in the home position. Both RA and Dec are at the ZERO point on the setting circle.

I slew E, W, N & S etc, then click PARK.

The DEC axis returns to home position, but the RA does not respond. It stays wherever I slewed to?

Can I try imaging in spite of this? I am worried this is indicative of a problem?

You mentioned: Also reset any mount model in eqmod

What do you mean by that, and where can I do that?

Hi everyone

On 16/01/2022 at 17:23, wimvb said:

I just went out to check the RA clutch mechanism. The clutch ring can be unscrewed a few mm, but not completely, which makes sense. This mechanism works as a bolt and a nut. The ring with handle that we see is the nut. Hidden inside the mount is its counter part, the bolt. When you loosen the RA clutch, you turn the ring clockwise and pull the hidden bolt half of the mechanism towards you, away from the RA worm ring. The bolt which pressed against the RA worm ring with its clutch plate, is now lifted from that. Here's a sketch that helps to explain.

The mechanism is fixed in place, and you can't remove the chrome clutch ring, unless you loosen the Phillips screws that hold the clutch mechanism in place. There is absolutely no need to do that.

For completeness, the DEC clutch is a little simpler. Here, the part that we see and turn itself presses against the DEC worm gear, locking it. You can't unscrew this clutch completely, because it is held in place by the ring that holds the counter weight bar in position.

I hope this clarifies things a bit.

Update.

Tonight I fine tuned BACKLASH on both RA and DEC.

There is no play now whatsoever in both axis.

I connected the mount in NINA, and slewed to all extremes in all 4 directions to make sure there is no stiction or issues.

Everything seems perfect.

Its a clear night, so I thought I might take the mount out for a CALIBRATION first in PHD2, and see what guiding might be like on a short imaging run.

The issue is: The mount will NOT PARK to the home position? DEC parks just fine, but RA does not park?

In EQMOD, I clicked the RESYNC EQMOD encoder button to tell EQMOD of the home position, but still no parking in RA?

Do the issues ever end?

9 hours ago, wimvb said:

I just went out to check the RA clutch mechanism. The clutch ring can be unscrewed a few mm, but not completely, which makes sense. This mechanism works as a bolt and a nut. The ring with handle that we see is the nut. Hidden inside the mount is its counter part, the bolt. When you loosen the RA clutch, you turn the ring clockwise and pull the hidden bolt half of the mechanism towards you, away from the RA worm ring. The bolt which pressed against the RA worm ring with its clutch plate, is now lifted from that. Here's a sketch that helps to explain.

The mechanism is fixed in place, and you can't remove the chrome clutch ring, unless you loosen the Phillips screws that hold the clutch mechanism in place. There is absolutely no need to do that.

For completeness, the DEC clutch is a little simpler. Here, the part that we see and turn itself presses against the DEC worm gear, locking it. You can't unscrew this clutch completely, because it is held in place by the ring that holds the counter weight bar in position.

I hope this clarifies things a bit.

Job done!

Third strip down in three days!!

So, it turns out the issue was with the BLACK SCREW LOCK NUT. 

While disassembled, I threaded the three grub screws into it, and observed, on the inner circumference, how far they went. 
 

Turns out that TWO of the three grub screws were not screwing in all the way. They would stop about 2/3 the way, so they would not lock onto the inner barrel. 
 

Using a 2mm Allen key, I cleaned out the three holes. There was some brown muck in there. A touch of grease on the inner threads of the three holes, and reassembled the whole mount. 
 

This time I noticed that the grub screws required MANY more rotations. 
 

And VOILA!

Job done. It’s now about 1/4 of a turn on the RA clutch from disengaged to locked. 
 

Sadly, I have one causality. 
 

The thumb screw has stripped, as I must have used in in anger and haste a thousand times over the past three days!

Using an M6 socket cap screw instead!

Happy days!!

I’m taking a break, then will address the inevitable HORRIFIC BACKLASH both in RA and DEC!

Thanks you all for your great help and contribution! Much appreciated!

Especially @wimvb

👏