Sunday, April 26, 2026

20260425 S30 + 300mm guided

Setup everthing before 10:00pm, I got around 30 minutes before sleeping.

I am still using the old PLA adapter, with minor adjustment.  The new PETG-CF was a failure during printing, some of the supports collapsed...

Aimming the Canon 300mm to M101, taking 180s exposures.  

Seems some major issue with that adapter.


Aimming the S30 to NGC 4631, taking 30s exposures, for 40 minutes.

Nice target.

Saturday, April 25, 2026

20260424 Adapting the NGF-CM to 2", visual observation on the moon, messier marathon M92

This is the second adapter made for the NGF-CM, this is a 2" nosepiece to connect with my Meade 8" SCT as well as my 85mm refractor.  It can be used with any telescope with a 2" focuser if it could provide enough focus travel.  Since the NGF-CM is pretty low profile, so at least the above two will work without problem.


Pulling out my Meade SCT to test:

It's not yet dark, but observing the moon is no problem.

The collimation is dead-on this time, pushing to 250x with the SVBony 8-16mm at 8mm is great.  I missed the view of the moon at such high power for long.  Good thing is that, the SVBony is nearly parfocal with my Explore Scientific 30mm.


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Setup my S30 at around 10:05, pointing at M92, a globular cluster:


Around 30 minutes of exposure, dedicated this short session to this target.


Friday, April 24, 2026

20260423 Night Session: M51 and Lyrid meteor shower

Did once in the afternoon, now this is the night session, started at around 22:10pm.

S30 aimming at M51 tonight.

Setup my Insta360 One R with starlapse, 5s each frame for Lyrid meteor shower.

It begans to fog up very quickly, hope it will clear up soon.


It didn't clear up at all until even the next morning.  The above was stacked with 30 minutes.



Thursday, April 23, 2026

JMI NGF-CM Renovation

It's always nice to give a new life to a long time trusted partner.  

My Tele Vue Ranger is a great example, and this is still my solar imaging workhorse.

Another project is my JMI NGF-CM.  I have owned a few JMI focusers, JMI NGF-S and JMI-CM with or without the digital readout.

I have replaced the focusing controller with a DIY USB rechargable controller box a few years ago.

This time, I even use a ZWO EAF with it.  It can be used with my Ranger, my Meade 8" SCT, my 85mm refractor and also even a Canon FD 300mm f2.8!  The switch could be done within seconds!


20260423 Solar Imaging

Didn't do solar imaging for quite long.

Just upgraded to a ASIAir Plus in order to do planet/solar imaging, so given the great sky today, why not?


I always love my nearly 30 years old Tele Vue Ranger, it has been given a new life with a JMI NGF-CM focuser, and better yet now with a ZWO EAF!  It keeps on evolving.  

I also got a solar finder for it, very effective indeed.


Centering the solar disc cannot be easier.

Despite seeing is no good, fine focusing with the EAF is lovely and accurate.

I took two videos with 1080 ROI, both hit the limit of 4G maximum file size in less than one minute.  Frame rate is good with this little box, I couldn't get too much more with my aging Windows laptop.

I am now stacking the videos by using the ASIAir Plus, seeing is less than optimal so why not do a simple processing from out of the box?  Stacking one video of 4G took more than nine minutes, not exactly fast but it might be faster than pulling out my Windows laptop.

Below is processed with a laptop, the ASIAIR version will be uploaded later.  I don't really have patience in this kind of seeing, so the exposure and mosaic was actually unusable.


Somehow I lost that image processed from out of the box with the ASIAIR Plus, anyway, my impression is that it's pretty nice.


20260422 M95, M96, M105, NGC 3384 and NGC 3389 mosaic

There is no unrecord objects during this time window, so I go back to normal imaging.  

I will fix my S30 in this area tonight, slightly more than 50 minutes of exposure.

Setup my Canon 6D with a 50mm f1.8 lens stopped down to f2.2 pointing at the Makarian chain, 180s exposures at ISO 3200.

Not a good one, just skip it.  Maybe the ASIAir is not controlling the Canon 6D good enough?  I don't know.

The dovetail slips, problem found.


20260421 Visual observation with friends on a cloudy night



We had a BBQ together, and the dark was not getting dark until later than 10:00pm?  But why not take a look at the moon?

So I pulled my 85mm refradtor out and set it up on the SVBony mount.

Some of them had their look through the eyepiece for the first time.

Afocal imaging was a must have action.


Sunday, April 19, 2026

20260418 Another Clear Night, marathon and also Gemini assisted collimation!

Come back from a gathering and it's not yet dark.  Good thing and bad thing, good is that I miss nothing, bad is that dark skies are getting shorter and shorter.

Let me do M103 first, this is an open cluster, should be easier with not-yet-dark-sky.  

It's kind of blocked by nearby stuff, so I relocated my tripod a bit to see if that could be done.  A bit marginal right now, see if I can capture it tonight or else it would mean next season!

Part of the field of view is blocked, got it badly.

And then M59 and M60 within the same frame:

Relocated the tripod to capture M49, not bad:

and then M61, the last target of the night:

I should be collimating my Meade 8" SCT but it's Sunday tomorrow so I better sleep earlier.  Let me set a deadline of 10:30pm.

Finally I did it with my manual SVBony mount, very nice.  I did AI assisted collimation by using Gemini to analyse the out of focus image and diffraction pattern.  The view is confirmed to be great on Jupiter.

There was some pinched optics formerly and it should now be fixed.




Saturday, April 18, 2026

20260417 Messier Marathon Session Again (!) Summer is Coming...

It is still not dark now (21:32) but I pulled out the S30 anyway.

First up is M40, this is a double star.  So seven minutes are more than enough.

Next up is M85, lots of satellite's track within just around 10 minutes.

And then M88, again with so many bright tracks around, around 10 minutes again.

M91 follows, around 10 minutes.

M53 will be the last target, 16 minutes finally.


A sudden clear night but with only around 1 hours of imaging time given I dare not to go  sleep late.

A pleasant surprise anyway.

Forecast raining in the next hour.


Tuesday, April 14, 2026

20260414 Comet 2025 R3 Hunting

Woke up at around 5:00am without alarm, pulled out the S30.

The sky is getting some twilights, low in the horizon, scanned with my Canon 10x30 IS but not much luck.  I have no star chart but just scan around near the horizon.

The S30 is struggling too.  The first frame was captured when it says horizontal calibration failed.  It was all white, the twilight was there already.  I should reduce the exposure after it settles with its initialisations and autofusing.

Time is running out, no chance to lower the exposure.

Mission failed, temperature close to zero wthout wind.

Call an end at 5:28am, mission failed.


20250413 Testing the reincarnated Canon FD 300mm f2.8

It can reach focus!  Autofocus works perfectly.

The testing target is M81 and M82, 180s exposure unguided, very fine subexposure.  No processing, seems like a big off centre from the vignetting pattern.  Will use PTEG with carbon fibre to print again for a stronger version.

And then switch to M13 for another test shot, 30s subexposure unguided.


M101 for 180s subexposure.


Setup the S30 along at 22:00, starting from M49, but then that part of the sky was not clear enough.  Gven up.

Turned to M84 and M86, will probably spend quite some time tonight on these.

And then M87.

And then M89, M90, M58 within the same frame:


An unexpected night, the forecast was partially covered but it is actually pretty clear.  Well worth to pull out a bigger setup.

Monday, April 13, 2026

20260412 M13 late night

Just back from Manchester and saw a great sky along the way back home.

Setup the S30 and point it at M13 from around 23:33, let see how much photon I could get.  18 minutes finally.

Then M64 for a short period of time, 21 minutes finally:

Well worth to re-visit it later.

Too bad that I don't have chance to test the 300mm f2.8 out tonight!


Wednesday, April 08, 2026

Transforming the Canon FD 300mm f2.8L into a telegraph with autofocus via JMI NGF-CM plus a ZWO EAF

The first attempt does not work out well, since it's difficult to print the 77mm thread.  

I have tuned the printing parameters for several times but it didn't help much.

Therefore, I design another adapter from ground zero again.  I found the original 77mm ring for the FD mounting mechanism could be reused and here's the prototype:

Some fitting issues, and I did the fitting with a cutter.

It looks great, with the NGF-CM fitted.

The whole model was refined and printed again.  I will use black PETG in the final version and add felt lined black sticked inside.


Three generation of equipments combined: Canon FD lens, JMI focuser and ZWO EAF.

I am so excited, and I hope I can try it out soon.


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Prototypes


Those thinner rings were the attempts of printing 77mm threads.

The bigger blue adapter was the first prototype of the redesigned adapter without the need of 77mm threads.

Summary: 3D printing could not be too precise, they are plastic afterall.  Expansion and contraction, annealing is apparently an issue.  They are pretty strong but to maintain accurate precision and collimation, you will need to redesign the whole thing.  Don't even try to push its precision or strength, try to avoid these.

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20260409 Additional Notes

Set the limit of focuser travel of the NGF-CM with ZWO EAF in my ASIAir last night.

Set the focuser position to the middle of the travel.

Confirmed that it could reach infinity focus with ample of rooms for adjustment, even without touching the NGF-CM.  So autofocus should work, but to be verified with the stars.


Tuesday, April 07, 2026

20260406 M102 et al

Continue my Messier Marathon with suboptimal sky.

Started at 9:23pm, summer time marks the beginning of less imaging time.

First up is M102, 28 minutes of exposure:

Next up is M105 with M95 and M96 (mosaic), will do at least one hour of exposure, finally 65 minutes of exposure:

Below will be left for the next time: M103, M85, M64.

Also setup my Canon 200mm f2.8 with guiding Markarian's Chain, containing M84, M86, and surrounding objects, etc.  

No polar alignment was done, just very rough focusing since my ipad air was dead.  Not really easy to do all these with a small mobile screen.  

Try to stack 30s exposures like the S30 therefore.

Very poor result.

Second attempt, reduce exposure to 10s and then stack.





Monday, April 06, 2026

20260405 M109 and Messier Marathon

The quest continue...

Started at 21:42 rather late but it cleared up a bit after the storm dave.

I will send the whole observation session with it, maybe around 45 minutes.  A promising target which deserves better treatment.

Finally, 1:7:30.