Tuesday, March 17, 2026

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.


Sunday, March 08, 2026

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.

Saturday, March 07, 2026

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.



Thursday, March 05, 2026

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.

Wednesday, March 04, 2026

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.



Friday, January 16, 2026

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.


Wednesday, January 14, 2026

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.