Monday, August 18, 2014

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!

Sunday, August 17, 2014

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.

Tuesday, August 05, 2014

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.


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.

Tuesday, July 15, 2014

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.

Saturday, July 12, 2014

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.

Thursday, July 10, 2014

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.


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.

Monday, June 09, 2014

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....