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.