Thursday, April 17, 2014

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.

Saturday, April 12, 2014

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.


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.

Friday, April 11, 2014

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!

Monday, March 24, 2014

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.


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.

Monday, March 03, 2014

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.

Thursday, February 20, 2014

20140220 M42

I was both a bit too busy and too tired physically to go out tonight.  But it was a bit too bad if I didn't observe with better sky, so why not just to have some simple observation from inside my home?

M42 was my target.

I pulled out my Ranger, with my 20mm widescan, it's quite easy to see.  Even the trapezium could be resolved at this magnification.  Jumping with a 2x barlows, the view is better for sure.  Then I pulled out my 4mm TMB planetary, and it becomes a bit too dim to view with direction vision.  Averted vision does help a lot and this is by far the best view of the night.

The chromatic aberration was not a problem for deep sky observation, even at higher magnification.  I was thinking whether I might go for a bigger achromat?  But that won't help on solar imaging...

Anyway, it's so nice tonight since I can concentrate myself on a single target visually.

Monday, February 17, 2014

20140217 Sun

The new H-alpha filter is still pending, the dealer is having problem with the supplier.  It has been several months already, so I've to stick with my white light filter.

Moving cloud today with high humidity, transparency so so as a result.  Seeing not good as well, so I only tried with my 2x barlows.

Prime focus, 1437 (GMT+8):-

With 2x barlows, 1443 (GMT+8):-

From low left to upper right, AR1977, AR1980 and then AR1974.