Collimation Screws for Meade 8" SCT

In order to facilitate collimation, I have bought a set of thumb screws to replace the existing collimation screws.

And to my surprise, the original screws were so short:

I wonder if they won't work when I placed them side-by-side.

AI suggests even longer length, but I have no choice but to buy these to test.

Buying Bob's Knobs will be several times of the cost, so it's nice to explore, trial and errors.

I have used Bob's Knobs maybe like 20 years ago when money was not matter, so I know how to replace them.  In short, I replace them one by one:

It's a good fit.  Despite the new screw is longer than the original.  On removing the "original" screws, I found that it was feeling loose, I began to think they were not original?  Or they were somehow abused before?  And that also explains why I never attained good collimation with them?

Guess what, the new screw has a good range for adjustment.  

They are not without problem, I want a bigger "handle" and the downside was that, the front cover could no longer be fitted on!

Finally, I used some distant tree to briefly collimate the scope.  The forecast said clear skies tomorrow night.  

20251230 NGC 1499 California Nebula - failed mosaic, wasted several hours

It's a very cold and clear night, the moon is hanging high in the sky.  

I have to go out tonight.  Despite the forecast will be clear, I won't risk my bigger setup.

The S30 will be working hard on NGC 1499 in mosaic mode.

After so many hours away, this is what I got.  

I believe the bright moon around is the killer, worst yet, I didn't set saving individual frames so this is really what I have got. 

For unattended shots, better save every individual frames.  At least you might have somehting useful at the end.

20251224 Testing of 8" SCT with reducer

Merry Christmas.

The forecast was swinging so I was never certain.  I tried to setup as planned.

Cloud rolled in, but I kept on.

I didn't do a rough focus first with distant terrestial target.  That makes the initial focus pretty hard.  I had to pull out my eyepiece to knee on the ground to have rough focus first before letting the EFA took over.  But then the EFA was not functionally well at first, maybe due to suboptimal collimation?

(Later I found that the stars from S30 was sort of bloated at the same night, too.)

Polar alignment was done by the guidescope by swapping the main camera with the guide camera, a method developed on the fly.  Not bad.

And then GOTO is a problem.  Plate solving with a narrower field of view did not perform well, I have to use the guidescope for GOTO autocentre.

(But then the guidescope and the main scope is not perfectly aligned.  Pumping up the exposure time for GOTO auto centre resolved most of the problem.)

Focusing could go very wrong again, I believe it's more like collimation issue?

Dew formed shortly on the large exposed corrector, and I tried to clean them up but it ended up forming a thin layer of ice there.  I have to connect two dew heaters to warp around the front, see if it helps?  

(After more than ten minutes, the thin layer of ice was still there.  Maybe I will need to attach it at the very beginning, or the output power was not enough?)

I have tried 30s exposure, 60s exposure, see how they work out.  Not promising.

Collimation screws were ordered by asking Gemini AI, see if it comes out well.

My LiFePO4 battery failed repeatedly, but after connecting to the charger for more than ten minutes, at least it seems to work now.  

But I'm using a small power station already, let's see.

Going back to the LiFePO4 battery at around 8:00pm, much more stable power source.

In short, Murphy's Law works perfectly tonight.   Everything went wrong.

Not exactly an enjoyable experience, but so much to learn.

Fortunately, the S30 is up and kicking.  Took some C23 Silver SIlver Galaxy, and some more IC 434 mosaic.

--

Notes after the observation:

1. I will not use the 8 inch SCT until I spend time on better collimation.

2. Even with the reducer on, the focal length was still a bit too much for me.

3. Aligning the guidescope will be very useful, for guiding it's no need, but for aiming it's very helpful

4. A dew heater is very important for the SCT, since the corrector is very much exposed

5. I have spent some effort to mount the guidescope on the original finder bracket of the 85mm refractor, it should make the setup easier to use

6. I shall use the 300mm f2.8 again until I can sell it eventually, see if I can get something more with it. 

20251222 Unexpected short session - Iris Nebula NGC 7023 or C4

Another unexpect session, I believe it won't last long.

(finally, I have got 2:44 hr!!!)

Not so good transparency, with moving cloud too.  

But since the S30 was so easy to setup, so why not?

Pulled out my S30 and ready to go at around 17:35, the Iris Nebula will be the target of the night.  I have placed the S30 on the platform for my telescope pillar.

Will be stacked with the previous 3 hr exposure later, or maybe I want to gather even more exposure?  Let's see.

On typing C4, it's the Caldwell catalog, from a British Astronomy who called Patrick Moore if I remembered correctly.  He was the author of the book on binoculars observation.

It's soaked with dew.

I used to store it in my dry cabinet after using.

20251220 Another Clear Night (Unexpected)

The power cables were not still not good, but can be used due to the clear sky!   Need to fix it later!

(Fixed the cables and tested them indoor and they seemed to work out well.)

The bigger setup is pointing at the Western Veil (NGC 6090), for 23 frames of 5 minutes.  I cooked, I went out, and then dinner during the process.

Swing back to M81/M82 later at around 7:30pm, (will remain for one or two hours), finally got 31 frames of 5 minutes.   I tried to go to IC 434 but then the power cable disconnect itelf.  Call an early ending.

The S30 will be spending time with M33.  Finally got more than three hours of exposure.

Allow me to put the unprocessed stacked below first, I shall gather even more.

Will switch to IC 434 when it goes higher up at around 21:40, and the cloud on that side cleared up especially when compare with the north where M81/M82 were.  

Will stay there for the rest of the night, hopefully will get more than half an hour of photons.  

Finally got well over one hour of data, will be processed later together with previous and future signals.

Observation note:  

1.  Autofocus failed several times.  I found that it's due to the fact that the motorised focuser was at the end of its travel limit.  

2. The new power cables was no good yet, I will have to do the soldering again.  May drill a small hole in the conductor and insert the wire inside before soldering.

3. The setup was left unattended from 17:40 to 18:30 at least since I will need to pick up my daughter.  No meridian flip is pretty safe, no rain hopefully.  (No problem at the end)

4. Veil nebula was a bit low after 7:30pm these days.

5. Polar alignment: swinging a bit from the zero position helps on finding brighter stars.

6. A layer of cloud can be detected from around 9:10pm, guiding star sometimes lost, signal reduced but I will keep on anyway.

7. I expect the field of view from my S30 is similar to that of my bigger rig, but I never compare.  I did compare them finally and they are indeed very similar.

Smart telescope against conventional setup

It's really a pleasant surprise to see some great results with a smart telescope.  

What we could get from small aperture and the cheaper imaging sensor is probably the most surprising.

Maybe I shall try shorter exposure with a bigger telescope?

Let say by using a 8" SCT with reducer, try stacking 30s or 60s shots. 

I am thinking about those smaller targets, distant galaxies and planetary nebula.

--

Let me summarise what I have in mind after several nights of using a smart telescope:

1. It's so easy to setup.  I will set it up whenever I have clear sky, no matter the time of the day, regardless of the temperature.  Setup time is zero, laziness is no longer an issue.

2. I would use the term "superlinear" gain.  I will always set it up along with my bigger rig, so my observation time was doubled at least.  Moreover, it increases my observation time since I will always set it up even when I have no energy to setup my bigger rig.  It redefines my total observation time.

3. This is derived from (2), if the best telescope is the one that you could use most, this is probably the best telescope.

4. Paradigm shift: shorter exposure time could be compensated fairly well by extensive stacking, therefore, I am inspired to try shorter exposure with some bigger telescopes.

5. Ease of use: the prime advantage of this setup is the ease of use, so it makes not much sense for me to use it in EQ mode.  In that case, I will go for my bigger setup.

6. Entry level camera: it is good as an entry level camera, but there is a catch.  I am something to say here.  Let say if you want to try more, you will need a big jump.  I mean to invest in a cooled camera, a good equatorial mount and a pretty large aperture telescope.  Going to 80mm might not show too much improvement, for something even bigger, you will want maybe 4 incher or above?  That implies a much bigger mount.  At maybe like several times of the cost, or you won't see much improvements.

I have to speak against myself about (5) here, if you want more, going for the EQ mode will be a natural step.  It also praves a way for you to go for a bigger setup.  Staying with the simplest setting has no learning curve, you learn nothing about the night sky and you learn nothing about how to set things up, not even know how to focus!  I always say astronomy is about polar alignment, collimation of the optics, and focusing (對焦、對光軸、對極軸), so by using these smart telescopes, you virtually learn none of these.

7. Portability: I nearly missed this point.  This super portable setup means a great chance to travel, for darker skies, or for a rare event.  Bring it along with your camping trip, or even night hiking would not be a major burden.

8. Image processing: the built-in software is good enough, especially for those who really enjoy photography but not fooling around with software.  As I have mentioned above, the ease of use is a prime advantage of this little stuff, so it makes not much sense for me to process the images further.  

Having said that, it could pave the way for you to go for a bigger setup later.

9. Visual observation:  this is a very important element, if you just want the picture, you can simply download them from the internet.  There is no provision to see with your eyes is a huge downside.  Getting photons light years away hitting your retina is simply the essense of amateur astronomy IMHO.

10. Exploring different targets:  it will give some ideas about what you can expect before using a bigger setup for more serious observation.

--

Permanent mounting for my S30:

1. Feasibility test: mount it on my fence, tall enough to get biggest visible sky, and to stay away for the light of my neighbour.  

I shall see if it's stable enough first.

2. Once it's done, I shall make a small sliding roof over it.  

A solid solar panel should do the job, charge up a battery pack to be used at night.

Sliding motor powered by tuya/google home.  

A rain sensor shall be installed so that it will be closed if it rains.

Sliding roof might be tuya/google home compatible.

20251218 Sudden Short Session (NGC 891 - S30)

It has been raining but forecast reveals a clear window from around 10:00pm.

So I pulled out the S30 for that.

Silver Silver Galaxy NGC 891 will be the only target for tonight.

(Got nearly an hour of photons, not bad.  There will be no clear sky in the coming few days.  Glad that I got this chance.)

I will be collecting some of photons from this interesting galaxy.

(Newer forecast reveals a good night this Saturday)

Some unprocessed image left in my ASIAir mini (M37, NGC 1499, NGC 7645)

M37 which should be taken quite early stage:

NGC1499, it should be a pretty old image, condensation on brighter stars?  Heavy vignetting or?  Dunno...

NGC 7635, should also be a older shot:

Time to focus on some particular targets after knowing what could be done with my setup.

20251216 Full Observation Session (Eastern Veil, M81/M82, IC 1795, IC1848 SH2-157)

It's all set, expect to do polar alignment around 15 minutes later.

The new power cable should work now.  I shall try to turn on cooling.

All set.

Target for the 85mm refractor:

1. Eastern Veil Nebula NGC6992 for around an hour for testing the setup

- there seem to be some focuser drift, autofocus point 9247, let's refocus after some time to see if it helps after tightening

17 frames were acquired, let's see how many of them will be useable at the end.

2. M81 + M82 + NGC 3077 for as long as possible, maybe extend for a few nights?

- Refocusing before shooting, autofocus point 9183.It might not be very colourful, but I love their shapes and configurations.  Just a bit higher than my roof, so catch the chance to capture them!

Targets for the S30, some more random explorations:

1. IC 1795 Fish Head Nebula (I set 20s last night and so it's using 20s exposure) for two hours

2. IC1848 Soul Nebula for twenty minutes only since it entered the light of my neighbour

It's better than expected, it confirmed that my last shot with the 85mm refractor was the Soul Nebula.

3. SH2-157 Lobster Claw Nebula, again with a few shots so I overprocessed it to bright something more

4. M1 for a few more shots, and I am going to get more frames before processing.

 

20251215 NGC7380 Short Observation

Short observation again.

It doesn't clear up until around 7:30pm and it will remain clear for about one hour or so.

I have no plan in mind, so I just stick to the recommendation by the wee s30.

NGC 7380 should be an small open cluster by itself, but the surrounding nebula is what attracts me.  It's fairly big and suitable for the S30.

First version processed by Siril:

Out of the box processed by S30:

I will spend the rest of the night with it.

20251212 A short but hopefully longer observation session

The forecast is no good, but the worst case is not raining.  

So I pulled out my bigger rig to test out my new Antlia Quad Band filter.  Also, I am testing my new wiring, basically connect the EAF and guider cam to the main cam.  It works out well.

However, my new power cable was not working.  I ended up using my old wire first.  I have to turn off cooling to make it works.

The main camera was pointing at the Soul Nebula IC1848, taking 5 minutes exposures.

I am somehow confused, the image came out seems something else that I could not identify.

I used Siril to process the image, I did background extraction, Cosmic Clarity, VeraLux Hypermetric Stretch, and Abberation Remover:

Antlia Quad Band seems generating halo around brighter stars?

And then I switch to the Lobster Claw Nebula SH2-157 in order to avoid meridian flip since I will have a meeting soon. 

After the meeting, I turned the main setup to M1 in the hope to capture some more detail.

(I was trying to clean up my asiair mini but I really clean it up, lost all other images, sad to find)

After setting up the big rig, I pulled out also my S30.  The Ghost of the Cassiopeia IC63 will be the target of the night.  Over two hours of exposures are accumulated.

Then I switch to M42 for some more mosaic:

Cloud did roll in to ruin some of the shots, but it's still a night worth setting the stuff up.

The bigger ipad is monitoring the S30 while the smaller ipad is monitoring the ASIAir running the bigger rig:

An image of the bigger setup before dark:

20251211 Cygnus Loop - Short Observation Session

This is again a short session, the break between clouds after Storm Bram cleared.

I got around 40 minutes of data, and it was a mosaic!

Very respectable result given this short exposure time.

I will use my Canon 200mm f2.8 with the ASI533mc Pro to do it when the sky turns better.

Images taken by Seestar S30 so far...

Got it around twenty days ago, I would use it whenever the sky was clear.

These were what I got, straight from the Seestar, meaning stacked, stitched or cropped, processed and color tuned by the Seestar.  

20251208 Short Session - M15 (45 minutes) + M35 with NGC2158 + IC 434/B33 Horsehead Nebula with NGC 2024 Flame Nebula

Before Storm Bram came, it has a small break of clouds tonight from 8:00pm, maybe for one or two hours.

It has been raining all days, even worse for the upcoming days.

So, it's the time for S30 again.  The sky was not entirely clear but something could be done especially it involves virtually zero effort in setting things up.

First up is M15, a small globular cluster:

Next is a open cluster M35, with a smaller one NGC 2158 next to it:

Finally, the sky was even clearer after the anticipated clear period, so I moved to the horsehead B33 and the flame nebula NGC 2024, around one hour of exposure:

Again, the best telescope is the one that you can use the most.

 

Equipment downsizing

This is a forever topic.

You have limited time.

The amount of clear skies are limited too.

Money and resources are limited.

I shall briefly try the 8" SCT for deep sky imaging with a f6.3 reducer.  If it works out, let say up to 2-3 minutes of guided imaging, maybe it worths to keep it.  Along with planet observation and imaging, three purpose should be good enough.

Or else I might sell it the SCT.

The Solarmax filter is to be evaluated further when summer comes.

Downsizing could mean a smaller mount.

I have reorganised the cables of my mount again.  The guidescope and the motorised focuser will go to the deep sky imager instead of going to the controller box. 

This is just cleaner.

And then the free ports could be used to power dew heaters.

--

I found that my ancient ipad mini can still run asiair, so it's good to use it as the front end.  

It's a pity that it cannot run seestar.

20251203 Short Observation Session M27

The forecast is bad, but I still pulled out the S30 again.  

Zero setup time virtually.  I have a rain sensor outside, so tearing down is quick and simple as well.

The best telescope is the one that you can use most, the S30 is definitely a winner.

Planetary Nebula should be good target, as long as star clusters.

AI really saves a lot of time on planning, I set M27 the Dumbbell Nebula as the target.

With only a few minutes of stacking, colors are shown.  Below is around 1 hour of exposure:

Some more targets for this season: M57 the Ring Nebula, NGC 7293 the Helix Nebula, NGC 6543 The Cat's Eye Nebula.  

Let me try them out one by one.

20251202 Short Observation Session with only S30

Comet 2025 K1 Atlas 30s exposure for 2 hrs

NGC7789 20s exposure stacked for 1 hr, exposure lowered due to field rotation

C17 and C18 20s exposure stacked for 30 minutes

No edit, direct output.

20251125 Electronic focuser added

I started using my 85mm refractor for imaging in the last session.  We have clear sky again tonight so I inserted the electronic focuser in the imaging chain.  Autofocusing by the ASIAir is simple but it takes some a few minutes.  

The first result was bad, but then I do the whole thing once more and it comes out great

Not bad it seems and I will let it run for at least one or two hours, NGC6888 or the Crescent Nebula, or maybe even leave it for the rest of the session since I am rather busy.

The 85mm refractor was calculated to be 511mm.

The guidescope setup was about perfect, just a minor tweaking on the focuser will do the job, highly repeatable and that saves a lot of effort in the cold air outside. 

The S30 is going as well, there's simply no reason not to pull it out.

It's taking image of the Iris Nebula NGC7023 or the Caldwell 4 and I will probably leave it for the rest of the night.

--

Some processed shots, I really have to study Siril.

I could see some artifacts after extreme stretching... need to investigate why, the CMOS sernor has not visible dust or marks or whatsoever.