20140825 Sun

The sky is pretty decent today, excellent transparency at 8/10, seeing rather good at 6-7/10.  I got plenty of sunshine from inside my home, with my Nexstar SE mount plus the newly repaired windows, I have far more time to observe now!

First up is an image taken at prime focus, I'm going to make a simple reducer to get a full disc at one shot, taken at 1516 (GMT+8):-

The hedgerow prominence on the 8 O'clock position is an eye catcher definitely, so here we go with a 5x powermate, taken at 1519 (GMT+8):-

Keeping at 5x, here's the other side with a semi-detached prominence, taken at 1522 (GMT+8):-

AR2149 at 1523 (GMT+8):-

AR2150 and 2151 at 1525 (GMT+8):-

AR2146 at 1527 (GMT+8):-

Going back at 2x for wider field of view, first up is a combination of AR 2149, 2150, 2151 taken at 1531 (GMT+8):-
 

And then finally, the area around AR2148 taken at 1533 (GMT+8):-

I really love those filaments....


I'm still not very competent on tuning the T-max and RichView combination, still exploring and I expect more.

It has been quite long ago for me to take so many H-alpha images in one session, very enjoyable.

I'm going to use this setup a lot hopefully:

20140824 宣道園 BB 312 觀星活動

基督少年軍 312 生活營觀星活動

I bought my Nexstar SE mount together with my C5 OTA, I found the 20mm widescan not very nice for beginners, eye positioning is not trivial enough for some of the kids.

We went through some basic knowledge about the sky: constellations, star colors, the concept of light year.

We observed Saturn until it disappears behind a tree, and then we visited M6 and M7.

Time is too limited, but the kids enjoy.

GOTO is accurate, tracking is superb in this kind of situation: queuing and observing.

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When I arrived home, I found that the alt arm is getting loose, and to re-tighten it, I just need to remove that little plate where the power socket and the power switch lies in.  Simple and effective.

20140818 Sun (resuming solar imaging!)

This could be considered as the official day which I resume solar imaging at home!

Previously even after I got my new filter set, I didn't get a proper mount, and my window couldn't be open widely... but these were solved.  The focuser is good after regreasing but a motorized focuser would be better.   Balancing is not a huge issue when the scope was pointing directly up!

I was trapped first my the internal reflection of the sun which results in an ugly image but by slewing around, I found a much brighter sun which is the real image.

Transparency 5-8/10, seeing 3-4/10.  Rather windy since the scope was shaking during moments with stronger wind.

Prime focus, taken at 1308 (GMT+8):-

I was not familiar with the new RichView plus T-max tuning, need some more time to train myself up...

5x, taken at 1324 (GMT+8):-

I also watched using my 20mm eyepiece at prime focus and with 5x Powermate, confirmed that the sky is foggy (thin cloud) without good seeing too!

Windows repairing

I finally got my home windows fixed yesterday.

How does it relate to astronomy?

Since I took most of my astronomical images from inside home.  Solar imaging, lunar and planets and that's why the windows are so important, if I couldn't open them wide enough, I even couldn't point my telescopes to those targets.

I will hopefully resume production soon.  Now given my Nexstar SE mount which can sit low in my window platform, I could even aim higher from inside window. 

Solar imaging is ready with my new H-alpha filter set but then I will probably need to handle the balance issue.  A motorized focuser will probably help in shifting the center of gravity back to the rear side, in addition to the ease of imaging. 

I can also retire my Mark-X for indoor purpose due to its bulkiness, no more need to use that DIY dec motor.

20140805 Mount Initial Orientation

Tonight cloud was floating around, and with Saturn just outside, why not setup my scope?

Initial alignment was simple with my Rigel Quick Finder, but I soon found that there is a problem on tracking, the mount seems to track wrongly in the alt. direction!  I guess the problem was due to the fact that, I placed the mount on the right side!  I guess the Nexstar mount has an assumption that the scope should be placed on the right!

Since transparency was bad, I dare not to do the alignment again.

I guess this might be my last observation from inside home before the windows of my home got fixed, I found it rather terrible to open the window too much now.

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For even simpler alignment, I will modify my finder bracket to accept my laser pointer shortly.

20140728 Nam Cheong Playground

This is a very short observation session with my kids.  We went with my Nexstar SE mount, together with my C5, just a small bad plus the mount on the hand.  The mount sat on a flat bench in the playground, but occasional train movement nearby was proven too shaky, but anyway, it settles fast.

Alignment is easy, but there are too many trees to block the view, not to say the even worst light pollution.  Basically we could just see the planets and the moon.

Quite enjoyable, due to the simplicity.

20140715 Saturn

First time doing planet with my Nexstar SE mount.  Seeing poor at 2/10, transparency also low at 4/10, I believe.  This is done with my white C5 at f/20.

At 1/15s, gain was pushed to 80% which indicates poor transparency.

Visual observation with a 20mm eyepiece renders a solid image, but pushing to 125x by adding a 2x barlows, image becomes a bit too dim.

Tracking is very nice, however, the initial alignment is a bit difficult inside home given a narrow view angle from a small window.  Given the alignment is done, GOTO is rather accurate as I can quickly go to the Mars even at 62x!

I will do it again soon whether the sky gets better.  Saturn is quite nicely positioned this year.

20140711 Moon, mount testing

This is yet another test of my Nexstar mount.

A table top mount is good in the sense that it can aim higher since it's lower!  And without the tripod, it could get closer to the corner to gain wider view.

This is a testing shot at 2400mm prime focus to see whether the tracking is good enough or not.  So far I'm satisfied, even with solar system alignment with the moon alone.

Celestron Nexstar 4/5SE mount

I got one used without the tripod.

The first impression is good.  The mount is mostly metal, it's stable and the capacity is good.  I bought it down stair to try it out on the road side.  I just placed it on the road side.

GOTO is accurate even with solar system alignment, i.e. I pointed it to the moon and let it go!  Going to the Mars is fine enough, Saturn was blocked by a lamp post.  But the general direction is correct.

In order to see whether it was stable or not, I plugged in a 4mm eyepiece to check with the moon.  Focusing was easy, image was stable within one or two seconds.  Tracking was smooth and no shaking...  Later I realized that it was 312x!

People said this mount is better with the 4" Maksutov than with a 5" SCT, but I found that it's enough!  This mount will be used for solar imaging with my Ranger, so I consider it a nice purchase.

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On the next night, I tried to use for my solar setup.  Yes, I did it at night.

The Solarmax filter makes it seriously front heavy, I've to slide the balance plate all the way to the other side to reach proper balance, but then the rear side will hit the mount base when the scope was pointing up. 

I guess I will need to add some weight at the rear side for balancing.

20140609 Sun taken through window glass

The window was broken so it couldn't be opened, I was forced to take image through the window glass:

The result was so ugly....

20140526 No tracking solar imaging

The Sun is still in a bad place from inside my room, and it is impossible to use my Mark-X for tracking.

1436 (GMT+8), at prime focus, no tracking and thus shifting and expand during stacking:-

 

1438 (GMT+8), with 2x barlows, no tracking and again shifting and expanding during stacking, the zip-zap line on the bottom is the artifact:-

I will try to keep on imaging even no tracking is possible.

20140428 Sun

Let's show the result first.

First one taken at 1514 (GMT+8) at prime focus:-

Next one close up at 1518 (GMT+8) with 2x barlows:-

I didn't look at the sun for long in H-alpha, and I didn't do imaging either.  And this is the first time I got my hand on the RichView tuning.  Seeing was very bad at 3/10, cloud moving around rather quickly with variable thickness.

Problem One: I couldn't use my Mark-X since the viewing angle was very bad, so I was using hand tracking or better say without tracking.

Problem Two: The new Solarmax is very front heavy, due to its bigger size and the added RichView tuning ring...

Problem Three: My DIY dec motor was not working for some reasons, I got to check.

Problem Four: I don't have a motorized focuser right now... 

Anyway, the result is rather encouraging.

C5 First Light: Collimations!

Guess what, I spent over 1 hour for fine tuning the collimation. 

I first use a low power eyepiece, defocus the star and adjust.  Next, I put in a high power eyepiece, again defocus and fine tune the whole thing.  Finally, I put it in focus and check the airy disc, fine tune again.

Next I put in my Lu070M, and re-adjust the whole thing.

If you got a SCT, the first light should be on collimation!

Accurate collimation is critical, while some collimated scope is not really stable since not all the collimation screws are tight.  So, once you reached a good collimation, tighten each screws incrementally until it's rather firm in place, don't over-tighten, however.

This is also a good test for my DIY DEC motor, backlash is rather bad due to the poor motor mounting and there's no backlash compensation in the DIY hand controller, however, it's very useable.  At high power, after adjusting the collimation screw, the star will simply move away rather significantly, sometimes even out of the field of my 1/3" CCD, but then a dual axis motor will help to bring it back effectively.

My 4th C5 OTA

Believe it or not, this is my 4th C5 OTA.

I bought a Nexstar 5 and used it for quite long, and then I sold it after getting a 4" ED refractor or something like that, but I was soon caught by the portability bug.

I bought another Nexstar 5 OTA, and it was a lemon, I sent it back.  And then get another one, but soon sold due to financial reason shortly.  After a few years, I got this one, and this is the classical white OTA.  It's made in the US, the visual back has a single lock screw.

Collimation was very well maintained, only minor tweaking was what required, I will fine tune it further with a star.  This is a nice balance between portability and aperture at a very reasonable price, it's so unique.

SMF60-10 first light

This is a dangerous one, since that 82mm to 77mm step down ring is not very secure, so I was hand holding the filter all the time... of course, it won't drop easily, but consider its price, I won't give it too much confident.

Tuning the T-max and focusing is difficult in that case.  Also, the objective was partially blocked by the window frame since the sun was not in a good observing location in the sky with respect to my home.

I forgot the H-alpha view indeed for most of the time I was doing imaging, and my Solarmax 40 has be sold rather long ago... the impression of the new setup was good!  Prominence and surface detail was rich, not much better than the Solarmax 40 I would say, since I was observing at low power.  Also, focusing or the T-max or the RichView was not tuned carefully as well.

The bandwidth and illumination is very even, much better than my Solarmax 40 setup.

To give it a more secure connection, I would buy a 77mm male-male macro coupler, or two step rings screwed together to form such an adapter.  Dual male adapter is available from ebay at over $100 HKD shipped while it was like $20 HKD from taobao but remember the shipping cost.

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I managed to get one at $38 from a local shop, factoring in the shipping from taobao, it's a fair deal.

Testing it on the Solarmax plus my Ranger, it's a very firm and secure setup.  I'm going to test it out soon!  Getting excited!

Clearing up and restructuring

Since my last major selling of equipments, all my stuff could be easily packed inside.  I didn't care to tidy up and there's no need.

With the arrival of some new stuff, I made up my mind to re-organize all the stuff.  I raised up the board to enable me to put in those bigger stuff on the lowest level.  Notice the bigger hole on the left.

The next lowest level was for stuff not very often used.

On the next level, my Ranger and my Mark-X plus the eyepieces and barlows.

On the upper level, my photography stuff... I just had four lenses left namely the kit lens, a 50mm f1.8, a 8mm fisheye, and a 200mm f2.8.

Everything would be basically ready by the next week, except maybe for a motorized focuser (JMI NGF-S or NGF-CM or similar) which I am still hunting for.

Solarmax II 60 and BF10

It arrives and it's much bigger, both the box and the filter itself.  I've to reorganize my equipment cabinet to fit it inside.  The coming C5 OTA will be placed along nicely.

It now comes with a RichView tuning ring in addition to the T-max tuner, I've yet to try it out to see how it works.

A very thick and large chunk of metal, probably requires more counter weight and will make the scope very front heavy.




The ERF side has 82mm female thread, the telescope interfacing side has 77mm female thread and 82mm male thread.  So double stacking requires no adapter, but I don't think I will go that route.

I will need to buy a 77mm male thread to 82mm female thread adapter ring (step up) in order to fit it on my Ranger.

Longing to try it out!

20140324 Jupiter

I have a brief look at Jupiter with my Ranger tonight.  My GOTO Mark-X is not useable due to the poor viewing angle, my 410 head did it marginally. 

Finding it with my 20mm widescan at 3+ degree field of view is easy, and then I zoomed in using my 4mm at 120x, quite a nice view despite the cloud around.

Imaging is rather impossible, unless with an iOptron Cube like mount which I owned before, but the aperture and quality are both very limited.

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I watched the dealer's page and Meade supply seems resumed, and then I send him an email, my new solar filter will probably be ready earlier next month!  Longing for that, need to make an adapter for my Ranger first, and also get a JMI NGF again!

20140324 Sun and the testing of the motorized DEC

Cloud floating around, it's virtually impossible to image.  Got the follow as a test of the motorized DEC, 1602 (GMT+8):-

Backlash is obvious but it is still perfectly useable given you had a bit patience.  The DEC motor is driven by a 9V (7.4V actual) battery, the speed is about right.  I will make a better hand controller for it.

Motorizing the DEC slow motion control

This is a video of the first integration test by using a rather soft metal plate to fix the motor in place.

I've used it with a telescope this morning at different voltage level. The view through the eyepiece shows that, at 12V DC input, the slewing was responsive and no backlash could be observed at 24x but the slewing speed could be a bit too fast. By going down to 7.4V, backlash is more observable but still very acceptable, the slewing was far slower for fine tuning. In fact, it could be even slower at higher magnifications. I guess I will settle down with a 9V (actually a 7.4V Lithium battery in the form of 9V 6F22. Therefore, I shall get a box which allows me to mount two buttons plus the 9V battery inside, maybe a small variable resistor.