20260329 Clear with showers, occassional stormy

Started at around 9:33p (summer time started)

First target is M44 which is pretty close to the moon, but open clusters should be fine.  

6.5 minutes exposure

M63 for 12.5 minutes

M94 for 16 minutes:

M3 for 18 minutes.

Stopped eventually due to shower.

20260328 Messier marathon session three: thin Cloud Observation

Start at around 9:50pm.

M101 is the first target, I have very limited time tonight but I don't want to rush like the last time.  So I am spending more time on this target, 47.5 minutes.

M106 is the next and the last target, see if 10-15 minutes would be good enough.  Stopped at 13 minutes, time to sleep, there's one less hour tonight due to switching to summer time.

20260327 Messier marathon session two: clear Skies with sudden rains

I still too the plunge to continue my Messier marathon.

The first target is M45 before it's sinking too low, I expect to spend 20 minutes with it for a 1.3x mosaic.  Starting from around 20:40. 

It refuses to perform AI denoise at 20 minutes, saying that the mosaic is incomplete.  I shall wait a little bit longer, maybe until 25 minutes.  So sad further exposure ruined the stacked image, I didn't save any individual and so it's really less than useable.  Just a record, 25 minutes wasted.

Broken M45 mosaic:

I hope to do one more two more objects before closing.

M100 is the next one, really low.  Let me do 8 minutes or so.

And then M98 with M99 before they sink too low (also with NGC 4208 plus NGC 4237), let me do around 8 minutes or so.

Then M67 for 5 minutes.

Finally M65 + M66 and also NGC 3628 before it snows (forecast), so for 30 minutes.   Got only 13 minutes before cloud rolling in.

Not a bad night, the forecast was bad but I got a handful of targets done.

Canon FD 300mm f2.8L second generation

With my new 3D printer, and the help of my daughter who is keen on making 3D models, this project is realised so quickly and it's a BIG success.

It was pessimistic about the thread (77mm 0.75 tpi) but it turns out to be nearly perfect.

It can reach infinity focus with some rooms.  So now this little lens could do autofocusing with asiair!

Aside from using an eyepiece, I also use 533mc pro to test.  It works without problem.

Other than the above adapter, I will be making two more:

a. 2" nosepiece in order to be used with my 85mm refractor for fine focusing

b. SCT female thread in order to be used with my SCT

I can then sell that CYCK focuser.

--

I have removed the ebay ad of my Canon 300mm, will be keeping it and making good use of it.

I have ordered black PETG carbon fibre filaments to print a strong adapter.  My daughter has modified the adapter to have more threads on more secure connection to the lens.

JMI NGF-CM with ZWO EAF

Since the JMII NGF-CM is lower profile, I want to see if it could be used with the Canon FD 300mm f2.8L.

It might be able to replace the CYCK focuser entirely, to use with my Ranger like now, to use with my 8" SCT, and to use with my 85mm refractor for deep sky imaging.

The first feasibility test was to attach the ZWO EAF to the JMI focuser, to replace the existing JMI mini DC motor.

Original JMI mini DC motor removed.

Replace the coupler on the focuser shaft.  It was for the DRO controller which I had sold.  Now it's attached to a coupler bundled with the ZWO EAF.

Next step is to attach the focusing motor, and I have proper screws on hand fortunately.

The next test would be to try it out on the Canon FD 300mm f2.8L to see if it could reach infinity focus.  If that could be done, I am going to keep the lens.  I now had it posted on ebay but so far no one really placed a bid yet.

I did a handheld test and it works with a 20mm eyepiece.  Since the 533mc could take a 2" nosepiece, and thus saving 1cm from the 2" to 1.25" adapter!  This makes even more room for reaching infinity focus.

Specification of the adapter: everything like my existing Ranger adapter, except it's with 77mm female thread instead of 76mm.

The project looks quite promising.

I will certainly keep my Canon FD 300mm f2.8L if that could be done.  I will then be able to have autofocusing with this lens!  My 533mc has a relatively small sensor which works pretty well with this ancient lens.

Next step is to make a SCT adapter for the JMI-CM, and then a 2" nosepiece.  The CYCK focuser could then be sold!

20260325 M51 by Seestar S30

I should create a new entry for this M51.  

I got 1 hr 40 minutes of exposure:

Processed by the box, nothing else.

Surprise to see how this little Seestar S30 could do.

Glad to have a partially clear night suddenly.

20260325 Seestar S30 Messier marathon: Session one

Partially cloudy (maybe 2-3/10) sky, bright moon

Last time should be session zero, since this was the session I got the idea about a messier marathon.

So this is session one, I am going to capture a few open clusters.  Mainly a filling session, to catch some targets before it's getting too low or disappearing soon.

My first target is M36.  It is pretty close to the moon.  So I didn't spend much time with it, so 5 minutes first.  Less than optimal, will come back later if I have time.

My second target is M37.  Even closer to the moon.  Again, 5 minutes.  Less than optimal, will come back later.

My third target is M38 with NGC 1907, also close to the moon.  Again, 5 minutes.  Less than optimal and come back later.

Next one is M34, this is farther away from the moon.  But since it's just an open cluster, I spend 9 minutes on it.

Switching to M51 finally, one of the best targets of the tonight recommended by Seestar.  I will give it the rest of the observation time tonight.  At least 30 minutes, the one below was around 35 minutes:

Finally, accumulated for one hours of exposure.

Going from target to target quickly tonight, this is the feeling of running a marathon.

The sky is getting clearer, but it's time to sleep.

When the mini-observatory box is done, I could then leave the setup alone.

Seestar S30 Messier Marathon Log

Those marked with a (-) is less than optimal.

M1 2025/12/16

M3 2026/03/29 (*)

M15 2025/12/8

M27 2025/12/4

M31 2025/11/21

M32 2025/11/21

M33 2025/12/20

M34 2026/3/25

M35 2025/12/8

M36 (-) 2026/3/25

M37 (-) 2026/3/25

M38 (-) 2026/3/25

M42 2025/12/13

M43 2025/12/13

M44 (-) 2026/03/29

M45 (-) 2026/3/27

M51 2026/3/25 (*)

M63 (-) 2026/03/29

M65 2026/3/27 (*)

M66 2026/3/27 (*)

M67 (-) 2026/3/27

M74 (-) 2026/1/3 (*)

M76 2026/1/4

M81 2026/3/20 2026/3/6 2026/12/16 (*)

M82 2026/3/20 2026/3/6 2026/12/16 (*)

M94 (-) 2026/03/29

M97 2026/3/21 

M98 (-) 2026/3/27

M99 (-) 2026/3/27

M100 (-) 2026/3/27

M101 2026/3/28 (*)

M106 2026/3/28

M108 2026/3/21 

(-) is suboptimal

(*) means worth trying again 

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20260329

It's good to push myself to capture something even in the worst situation.

It's nice to get some ideas about the size, the location and the magnitude of more targets.

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.  

M97 The Owl Nebula was captured accidentally on the bottom right corner.

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?

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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.