Seestar S30 Messier Marathon Log

M15 2025/12/8

M27 2025/12/4

M31 2025/11/21

M33 2025/12/20

M35 2025/12/8

M76 2026/1/4

M81 2026/3/20 2026/3/6 2026/12/16

M82 2026/3/20 2026/3/6 2026/12/16

M108 2026/3/21 

New equipment - the joy of visual observation

It's a reclining chair.  

Observation with my Canon IS is just fantastic!  Now, I just want darker sky.

My neighbour keeps his light on all the night, and there is also a nearby street lamp.  

Nevertheless, scanning with binoculars are simply irreplacable experience.

 

20260321 Not so good sky - M108 Seestar S30

The sky is not very clear.  I will be using the SeeStar only tonight.

The target will be M108.  

I suddenly got a thought about running a Messier Marathon myself with the S30?

--

Equipment thoughts:

I will not upgrade my mount, since I won't use the 8" SCT for deep sky imaging.  

For planet imaging, my HEM15 will work with the 8" SCT.  

For deep sky observation, even my SVBony SV225 will work.  So, it's a keeper.

Maybe just sell that f/6.3 reducer and then done.

20260320 Jupiter and M81/M82/NGC3077/NGC2076

Setup the S30 for mosaic around M81, M82, NGC3077 and NGC2076.

1:37 hr of signal acquired.

One with latest AI denoise another is raw stacked.

Trying out Jupiter with my 8" SCT, collimation was off after quite some time.  

Some videos were taken at prime focus, I didn't take any after inserting the barlows.  Collimation was pretty off.

(result pending)

Focusing with the short pier is no fun at all, centering the Jupiter was not too difficult with the bigger sensor of the 533mc but I don't think it's much fun.  I am one more step closer to sell it, for visual observation a dobsonian might be better.  I don't quite like planet imaging any more.  Long focal length deep sky would require a better mount which I won't probably want.  Time to downsize?

--

20260321 Followup

The collimation screws were too long, it should be 8mm but mine were 12mm, maybe that's why they couldn't hold the collimation well enough.  Order has been placed to get 10mm collimation screws since I could get exactly 8mm.  The new one has thinner thumb holder was shorter, the lens cap might be placed on after changing?

On checking my blog, I was considering adapting the NGF-CM to the ZWO EAF.  It's well worth further exploration.

Mini Observatory Project based on SeeStar S30

A small garden storage box will be used with the following dimension:

56cm * 41cm base and it is 50cm tall.

A rigid solar panel will be placed on top of it, with the following dimension:

101cm * 46cm.

It will be used to charge an old car battery.  

The battery will make the whole thing more stable, and will not be blown away easily by wind.  The SeeStar S30 will be placed on top of the battery, making it close to the cover for unblocked view.

The battery will be providing power to the SeeStar S30, as well as some minimum lighting and maybe a small ventilation fan to keep moisture out.

Will try to add mechanism to close automatically when rain is detected.  

Automatic openning is optional.

--

20260319 Update

The storage box arrived and it's of good size.  

Strong and waterproof enough as it looks.

The solar panel is probably too big and heavy, I will need to find something else.

--

20260320 Update

Maybe the new solar panel should be placed on top of the storage shed, the exisitng flexible panel should be moved in the front.  This combination should provide far more than enough power except winter.  I shall then use the power station more now, maybe find a way to mount a powerful kitchen ceiling lamp to save energy in the long run.

My LiFePO4 will be charged via the power station.

The older flexible panels will be installed on top of the mini-observatory, to charge a car battery continuously.   This battery will be used for charging up powerbank for the S30, as well as to power fan and some backyard light?  

--

Solar panel installed:

Drill another hole on the side to let the wire goes inside:

Placed the battery and solar controller inside, need to find a way to "fix" it in a better location.  

Door closed, looked quite nice!

These two panels are relatively old.  One of them were damaged partially and the power output is reduced.  Anyway, just collect as much as sunshine as it could.  I have power banks which could be charged fully by the power station easily.

Need to find way to mount the new solar panel on top of the storage shed.

20260307 Canon 200mm f2.8 NGC 2174 Monkey Head Nebula + IC443 Jellyfish Nebula

I went back to my Canon EF 200mm f2.8 after testing my Canon FD 300mm f2.8.

I have used a Optolong Quad Band light pollution filtyer this time.  I am trying to compare it with the Antlia Quad Band.  Preliminary ideas:

1. the Antlia Quad Band should have tighter passband, you can see if even side by side, simply less light could pass through it

2. bloating stars are a side effect of (1), and thus the Optolong Quad Band gives less bloating bright stars as a result

On setting the things up, I found that I failed to focus my 200mm lens for unknown reason.  

In order to save valuable observation time, I went to use the Guidescope with the guiding camera for polar alignment.  I even used this combination to take images of the M45, the result was quite unexpected.  Seems like a monochromatic camera has a clear edge, despite it is not a cooled camera. 

60s expoure, 11 frames in total, taken with ASI462mm and the guidescope of 230mm focal length:

I aimed at M45 since I know there will be some bright stars for focusing.  Later, I found that the lens cap was not removed.  <GRIN>

Finally, I turned to NGC 2174 and IC443 for the rest of the night.  Quite busy area in the sky, quite of subexposure was affected by satellites.  Total two hours of exposure.

I then pulled out my S30 again, this time pointing at IC434 the horse head nebula.  Exposure of slightly more than an hour, pretty low in the sky, in the direction of a street light.  Field rotation pretty serious in that part of the sky.

It's never in a good position in the UK.

20260306 Equipment Testing: Canon FD300mm f2.8 on the double cluster + Seestar S30 in EQ mode

Canon FD300 f2.8 Testing:  Other than the double clusters, I have tried a number of other targets as well.  They will be used to demonstrate the lens.

EQ mode testing failed, since the Seestar failed to point at a clear patch of sky when doing the polar alignment.  It keeps resetting its WIFI for unknown reason.  I have given up and pointed it to M81 and M82 for the rest of the night.

1.5hr in total, altazimuth mode 30s subexposures.

My daughter came back and I setup my 85mm refractor on a SVBony SV225 mount for some visual observation.  I have used my Canon 10x30 IS as well.  Very fine session.

I tested a new zoom eyepiece which is better than expected.

20260304 NGC 1893 - Pillar mount connection changed - Comparing S30 and 533mc pro

I change the way the mount is connected to the pillar, should be more stable and consistent now.  That quick release bracket was removed.

Canon 200mm again, with Antlia quad band filter tonight.  The Antlia filter is creating bloating stars.

Recalibrated the guiding since it's quite erratic.

I then pulled out my Seestar S30 to point at NGC 1893 as well, the field of view is much narrower.  I shall compare them side by side later.

First up is taken by my 533mc pro, 300s exposure x 24 (two hours):

It should win hands down, better sensor, better optics and longer exposure.

Next up is taken by my Seestar 30, 30s exposure x 300 (1.5 hours):

The field of view is narrower, smaller sensor, smaller pixel, non-cooled, shorter exposures and shorter total exposure.  However, the result is still very respectable.

20260303 Long overdue clear skies (but with the near full moon)

It has been very long since the last observation.  Scottish weather is just fantastic.

Since the moon is hanging high, I have to avoid that direction.

Gemini suggested Heart and Sould Nebula with my Canon 200mm f2.8 and ASI 533mc pro.  I shall start doing polar alignment at 7:00pm and real imaging shall start at around 7:30p.

Accident: The 533mc and the guidescope/cam unscrewed itself from the EOS adapter, dropped on the ground but thank God, nothing got damage, not even a small mark.

I removed the whole thing inside home, dew formed on the light pollution filter and so it was not used in this session.

The final target was IC 1805.

I shall pull out my Seestar S30 too.  

Firmware update when the session begins, it's not unexpected after a long bad weather pause but it's certainly undesirable.

IC 1848 which is close to IC 1805 for the S30 tonight, AI denoised by the SeeStar, no other processing.

20260115 IC 405 Flamming Star Nebula + M31 + IC 410 Monkey Head Nebula

It's clearing up.

Gemini suggested the Flaming Star Nebula (IC405) as the target.  I am asking for group of targets that fits into the field of view, so IC410 will be there too.

When the S30 slews to IC405, I know Gemini cheated me since IC410 or NGC 1893 The Monkey Head Nebula was not in the same field of view.  I believe I will do it later tonight or in a later observation session.

Observation started from 1720 when the sky is not completely dark yet.

Over 4:15 hour of exposure accumulated (over 500 frames), with 81 dropped frames.

I then setup my 533mc pro with my Canon 200mm f2.8 lens guided, took light/dark/bias took quite a lot of time, I didn't do these before.  Got to develop a habbit and have a good library of these frames.  Focusing should be improved since I used the zoom function of the ASIAir for focusing.

M31 could fit into the field of view, so I will go for it.

Over 45 frames of 300s exposure accumulated, with dark/flat/bias at -10 degree Celcius:

To be further processed by Siril.

I kept the S30 running after I slept for the first time, pointing at the cone nebula (Christmas tree nebula) at first, but then I found it's sinking quite low so I switched to the Monkey Head Nebula IC410 instead.  Got around 3 hr of exposure:

Pretty nice results.  I believe I will be playing with my Canon 200mm f2.8 more in the near future.  I hope to take a combination of objects, that's a couple of DSOs in the same field of view.

20250113 Unexpected Partial Clear Skies

It has been raining all these days, but it cleared up suddenly.

The sky is not getting totally dark until now (17:10), the night is getting shorter.

Setup the S30 for some observations.

First target is NGC 1499 the California Nebula which is pretty high on the sky, but cloud started rolling in.  Maybe another typical night that only these smart telescopes could be used.  It simply didn't worth to setup anything more complicated.

It cleared up a bit later at the night, but there were still random cloud moving.

Got over 3.5 hours of exposure, over 450 frames stacked with over 100 frames ignored due to various reasons, mostly because of cloud.

Processed solely by the S30.

On taking the S30 back indoor, I saw a good sky but I was also too tired to setup anything else.  This is another example to demonstrate why these smart telescopes are nice for anyone: they simply extend your useable observation time.

SVBony 8-16mm eyepiece

It's a very nice one and it's going to complete my collection.

I was fancy about zoom eyepices.  Back in the good old days, I got a Tele Vue 8-24mm zoom which was considered as the only good quality eyepiece.

Things have changed.

Tele Vue got those nice planetary zooms later and they changed the world.

I got a clone later, from SVBony and I was impressed.  

Modern day zooms are higher quality and better yet, the apparent field of view is good too!

A 32mm 2 incher will be the finder eyepiece for any telescope.

My trusty 20mm widescan 1.25" will be the finder for 1.25" only telescope.

And then that 3-8mm will be good for smaller refractors, offering high power.

So, the 8-16mm will be good for SCT.

For my 85mm refractor, the widest field of view will be with the 32mm.  Offering 16x with a wobbling field of view of more than 5 degrees!  It beats many binoculars hands down.

Highest power could be attained with the 3-8mm, 170x is very respectable, given its 0.5mm exit pupil.

For my 8" SCT, the 32mm will yield 57x with 1.4 degrees field of view.

Highest power could be attached with the 8-16mm, i.e. 250x giving 0.8mm exit pupil, more than most atmospheric conditions will allow.

Case closed for visual observation.

From 32mm down to 20mm, from 16mm down to 8mm and then seamlessly from 8mm down to 3mm.

Guess what, I still have a 5x Powermate and a 2x barlows.

Experiment: Canon FD 300mm f2.8 with crayford focuser

I am selling this ancient self modified lens.

A sudden thought came to me, why not attach it directly to a crayford focuser?  It shouldn't be too difficult.

I have all the thread specifications, connecting adapters might not be too difficult to find.

I even removed the camera angle adjuster to test, but unfortunately, the focuser was a bit too long for infinity focus.

I believe that a short profile SCT focuser might work, and I actually have one.  Might try again later, I just treat it as a short break for me.

--

Equipment shuffling

A further thought comes.  I am trying to see if this CYCK could be attached to my Ranger tube so that the JMI NGF-CM could be released?

The answer is not simple.  

The Tele Vue Ranger has a 3" 24 TPI thread, while the CYCK has metric thread.

I should have fabricated a SCT adapter for my Ranger tube instead of custom made for the NGF-CM.  So it's very much irreplacable now.

I could go another route: attaching the ZWO focusing motor to the JMI NGF-CM?  I might work but then it's not easy to adapt the NGF-CM to another telescope since it has nothing but a groove like attachment.

If I could find a NGF-CM SCT adapter, the whole thing would become possible.  However, the JMI seem dead?  It's not easy to come back such an adapter.

20260105 Remote Seestar S30 and Meade 8 with reducer deep sky testing

Setup my S30 on remote mode, I can control it when I was outside.  

I did try to do that many years ago for solar observation, but it never worked out well.  

Such a economical and versatile setup, simply amazing!

I am capturing M33 again, and turn to the Rosette Nebula at around 9:10pm.

--

I will setup my Meade 8" to do something.

Configuration: SCT - Reducer - Focuser

Note on focusing, I've to turn anti-clockwise after inserting the reducer.

Polar alignment works pretty well with the reducer on, plate solving was fast too.

Effective focal length is 1171mm.

The first target was M45, yes!  Such a wide field target but I only target on Merope, doing some 10s exposure.  Guiding does not help, or I should say it makes things worse.  I turned it off and let it drift, it works better than without guiding.   There were72 frames only, so nothing could be shown virtually.

My guidescope was just 230mm which does not help indeed.

The next target was silver silver galaxy (NGC 891), I turned on guiding so that at least the framing will be retained.  Guiding was much better this time and so I tried 30s exposure.  It looks good so far after 17 frames.  Started at around 9:10 as well.  

At around 9:45, I found that I was doing only 10s exposures... I got around 300 frames, Meade 8" with reducer, fairly lazy processing by Siril.  The result is less than ideal, but the total exposure was very limited too.

Did some Jupiters with reducer on, should remove it but I was too lazy.

2053 and 2055 (UT), the amount of detail is good, larger aperture really helps.  I shall remove the reducer and put a 2x barlows in next time.

The sky was foggy and it indicates better seeing?

Turning to M1 for some test shots too.

Seems like it's not very successful for shorter exposure imaging.

Conclusion: 

Dark, Flat, Bias should always be taken.

Flat should be taken everytime when I do imaging, probably at the very beginning or at the end of all target.

Postlude: my 51st birthday under a starry sky

I guess I should use Hong Kong time as the reference when treating birthday.

Anyway, I gave myself a chance to spend under the starry night.  I didn't go out with my daugther for her band and I stayed at home alone.

The experiment of using a SCT did not work out well, most probably due to dew formation.  SCT is a  dew magnet since the corrector is very much exposed, I have bought a dew shield and a dew heater.  So, shall try again later.  

Collimation should be fixed, but then guiding does not work out well too.  Getting a long focal length guidescope is too much luxury and I shall change the mount too?  

Planet imaging is not as enjoyable as before, selling the SCT at the end?  Or at least selling the reducer?

However, the SCT is still good for visual deep sky observation.  M42 is showing some very delicate structures even in my garden.  I always love visual work.  Or going for a dobsonian?

If that's the case, maybe selling the harmonic drive mount, the cooled camera, the motorised focuser altogether?  Stay with a S30 or those smart telescopes?  Call me lazy.  

But I know I will keep playing them at the time being, maybe try one or two more years.

Maybe it's time to use those smart telescopes to do some research, like automated studies?

20260104 M76 and NGC 2237 Rosette Nebula

Full moon still around, snow just stopped.

Setup the S30, taking images of M76.  Got two hours of photons.

Next is NGC 2237 the Rosette Nebula, not much time left since I would want to sleep earlier tonight.  

If I still have some energy later tonight, I will setup my Meade 8" for planet imaging.

-- No energy at last, so it's how and why the S30 shines!

20260103 Another full moon clear night

S30 was setup.  

The first target will be M74.  Straight out of the box:

I will try to test my 85mm refractor for Jupiter tonight.  Seeing seems no good here, and maybe a refractor could bring more than a larger SCT?

(Maybe I shall also try unguided short exposure with the refractor too)

S30 Moon using planet video mode

While waiting for the Jupiter to come into view, I tried 30s exposure at f/6 (slower than S30) and for maybe around 15 minutes.  Unguided.  See how's the result.  Much better sensor, cooled to -10 degree celcius too.

After maybe like 15 frames, it already looks way better than the S30 for more than an hour!  This is a very good test.  I should do some dark frames, patches maybe from condensation could be seen.

(pending)

M45 is my next testing target, 60s exposure when used, autoguiding enabled.

First time trying dark/flat/bias in live mode, quite easy to use.

(pending)

Trying ASIAir video mode, it feels good with 20fps at 360p cropped, 24 fps at 240 cropped.  Good enough for a small refractor.  85mm refractor with 2x barlows: 

I would say ASIAir mini should be good enough for planet imaging up to around a 4 inch refractor with quite respectable frame rate.  Of course, nothing serious could be obtained with such a setup.  The video mode GUI is pretty intuitive and easy to use, maybe even better than ASICap.

20260102 Near Full Moon

After collimation, why not do some planet imaging?

It's cold and windy, so cannot really expect too much.

2020 UT at prime focus:

2033 UT with 2x barlows, more like empty magnification:

I also took a shot of the moon, but it's no good.

20260101 Unexpected expected clear skies

The forecast was a nice one, but then it was covered and it even snows.

After the snow, we had some clear skies but the near full moon was hanging high.

So it means a good time for collimation.  You cannot do much deep sky imaging like this, and the snow reflects moon light making a very bright clear skies.

Before collimation, I pulled out a new toy for my daughter.  An afocal adapter for simply imaing, the result is not bad.

I then do collimation with her using this adapter.  She recentres the target star for me after I did minor adjustments, and she judges whether it's good or not with me.  A very nice experience.  The new hand knobs are very good, even in cold weather.

The S30 was struggling to get some more photons.

I would say the SCT now is in good collimation and I will start using it again.  If the weather cooperates tonight, I might be doing some planet imaging.