Thursday, April 27, 2017

20170418 Jupiter

The sky has been cleared for a few days, and I finally cannot hold myself but to have some simple imaging time.

I placed the Nexstar mount plus accessories into a small backpack and hand holding my C5, heading to a nearby small playground.

I just set the scope up like this, to save the effort about dragging the tripod out.

The Nexstar mount has quite some backlash and the backlash compensation was not fine tuned enough, keeping the Jupiter in the field is not easy...

The collimation must be very bad.

Here is the result after processing;

And this is the prime focus shot, those with a barlows were too bad to show.

Thursday, April 13, 2017

Minor revamp of the Canon FD 300mm f2.8L

I removed the ugly hot melt glue and replaced it with eproxy putty.  I might paint it back later.

I tried to compare the focusing chip which utilizes the phrase detector, with the live view and the result is consistently effective and accurate.

And then I set it up on the Sky Adventurer, and it supports well, and the counter weight is far more than enough.  Both the internal RA motor slews well, and my DIY DEC motor works well, too.

You can also see the Polemaster above.

Really want to try it out under than stars.  I have several prime lenses,  a 8mm fisheye lens, a 50mm f1.8, a 200mm f2.8 plus this 300mm f2.8, and that should be enough for quite many targets.

Thursday, March 23, 2017

A smaller focuser controller

I have a dead 18650 charger, so I removed all the circuit board inside, solder two small switches on the top to make a small focuser controller for my JMI.

It's powered by a 18650 inside, I could even add a small rheostat inside to adjust the speed.

When I don't need to DRO control unit, for example, like for a more compact setup like visual trip, this small controller could be used.

Wednesday, February 01, 2017

20170201 Sun

Cloud keeps moving around today, seeing 5/10, transparency 4/10.

Don't really have time to fine tune to focus or the T-max.

0706 (UT), with reducer:

0710 (UT), with 2x barlows:-

0711 (UT), with 2x barlows, that interesting filaments attracted my eyes:-

The last image really shows how poor is the T-max, very uneven bandwidth across this little frame.

Friday, January 27, 2017

Polemaster and Sharpcap 2.9+

I went last night without any luck, the sky was too bad.

Tonight the sky seems a bit better, so I went again.  A nearby light polluted sky, with the polar region partially blocked.

Since I've tested with Polemaster software, and tonight I play with Sharpcap 2.9+.  If the automatic plate solving works, it's simpler for the Polemaster software requires manual pattern matching.

To my surprise, it works out very nicely!

Here's the screen shots of how it works... Plate solving success...

And then rotate along RA, success again... 

After polar alignment with Sharpcap, I proceed with the software of Polemaster and it works!   Confirmed the alignment.

And then I removed the polarscope caps, saw Polaris in the expected position!  I hope I could do some wide field imaging soon!

Wednesday, January 25, 2017

20170125 Sun

Glad that we still have some sunshine today, seeing 5/10, transparency 4/10.

0652 (UT) with reducer:

0655 (UT) with 2x barlows:

Keep on going...

Tuesday, January 24, 2017

20170124 Sun

We have some brief clear moments today, seeing 5/10, transparency 5/10.

0711 (UT) , with reducer:

0717 (UT), with 2x barlows:


BTW, I'm switching my job and my new job will start from mid-Feb... so at the time being, I've more time to observe.

Monday, January 23, 2017

20170123 Sun

Let's keep thing as monochromatic as it should be.

Full disc at 0700 (UT), taken with a reducer.

 Close up of AR2628, with a 2x barlows, 0705 (UT):-

I have to push the exposure and gain really high to show this hedgerow, 0709 (UT), again with a 2x barlows.

Cloud moves around today, seeing 5/10, transparency 5/10.

Sunday, January 22, 2017

20170122 Sun

Seeing quite good at 6/10, transparency 6/10.

0706 (UT), with reducer, rather sharp and finer detail could be seen.

0714 (UT), with 3x barlows, Newton's ring persist as well as some dust artifacts, I did not drift around the image enough while capturing.

Switched to use AutoStakkert!

Wavelet goes back to Registax, and final touch with PS.


I always said, there are three important basic techniques for astrophotography namely: collimation, focusing and polar alignment.  And in Cantonese we said: 對焦,對 pole, 對光軸...

For focusing, I have a motorized focuser.  For collimation, I bought the original Bob's knob for collimation.  And now for polar alignment, I have just bought the QHY PoleMaster!

To use it in the field, I use my Teclast tablet via OTG cable.  And it connects without any problem, I've tried it in day time but the exposure control is very limited so that even at its lowest setting, the screen white out.  Can't wait to test it tonight in a nearby location, I hope I could find a place where the Polaris is visible.


 I really got chance to try it out in the field on the same night.

I only got time to go to a nearby playground but then I don't know if Polaris is visible or not there... After more than half an hour, I guess I made it.  Note the bright thick line across was from a distant (not too far away) tower crane!  The Polaris is barely visible, and then light pollution was very severe so that pushing the gain/exposure further will only white out the whole screen.

Finding the center of rotation of the Sky Adventurer is not easy by pressing the button since it's just too slow.  And instead, I disengage the clutch and move it manually but this is not recommended as stated in the user manual.

Finally, I pulled out my DSLR and tested with my 50mm lens.  I stopped the aperture and set ISO low so that I could do a 3-minute exposure under such a sky, star remains pinpoint, good news.

Saturday, January 21, 2017

20170121 Sun

20170121 0649 (UT), Ranger with reducer:-

0656 (UT), 3x barlows, 90% resized, AR2625 and AR2626:-

Friday, January 20, 2017

20170120 Sun

Excellent transparency (Hong Kong standard, of course) 9/10 with quite nice day time seeing at 7/10! However, excessive dust on my CCD renders higher image scale useless... I guess a 3x barlows should be ideal. First up is the full disc shot, with the reducer at 0614 (UT):-

And then two high power shots without the reducer, but with a 5x powermate, taken at 0628 and 0633 (UT) respectively.