Saturday, May 30, 2009

Goodbye my Cosmicar 150mm f/3.2

It's a very nice CCTV lens for my DMK, but I have to let it go because I wanted to gather more paypal money to hunt for good 2nd hand deal. Guess what I'm aimming for? I'll concentrate myself on DSLR when deep sky photography is concerned, and I will try to keep the focal length short to do without guiding. Right now my paypal account should have enough fund for my target item. Very nice!

The PST hacker's version with ERF is still waiting for a buyer, I wish that it will have a good new home.

My CCTV lens line up will have two lenses left: a 6mm f/1.4 as well as a 75mm f/1.8. That wide field CS mount 2.3-6mm is pending for a local friend. Keeping two are sufficient for me. My equipment cabinet is now having some spaces for new stuff!

Friday, May 29, 2009

DIY USB Battery Box

When I sold my C5, I have to sell my USB battery box as well, since that one was also the controller of the motorized focuser. My TG-SP II is using a DIY USB power cable to run, and thus I made another one today.

First of all, I will need a small plastic box. I looked around my home and found that little box for dental flossers should be a good fit, so I pour all the contents into another box.

By fitting a USB back panel socket and a 4AA battery holders inside, it seems to be a perfect fit, so I drilled two small holes to fix that USB back panel socket there. Those small holes could be made by using heated screw driver, very simple and elegant. The rectangular slot should be made using cutter carefully, it's not hard either.

I placed that socket on the side since it's the only feasible location. Originally I wanted to put it on the top but then the battery box won't fit afterward.

Last time, I simply connect the wires with the original shielded thick cable, but this time due to the crowdy small box, I removed that shielding. The red and black are for power, and the green and white are for data and thus they will not be use in this case.

Again, check with a multimeter to make sure everything is correct and expected. Don't risk since some of your equipment might break if connected wrongly.

Finally, solder the cable correctly, and check the polarity again.

It's a very tight fit, originally I didn't check the fitting with batteries but this battery box would become a little bit bigger with battery inside. Luckily, it can still be closed with a little bit force, no need to put foam for this box.

I checked polarity again and then I plugged in my TG-SP II, and it works fine! I guess that I ain't going to extend this one to control focusing motor because I have no more SPDT switch and I have no more mono socket on hand.

This simple project costs $5 HKD (the battery holder) only.

Motorizing the DEC of my TG-SP II

On clearing the cabinet yesterday night, I found something interesting, it's just a small gear which was left idle from day one. I guess that it comes with my LXD55 as a spare part, and what makes it so interesting is that it fits the slow motion control knob of my TG-SP II perfectly!

Then I pulled out the motors which I had on hand. The Nexstar motor is a little bit too big, and the encoder is not going to be useful. Another DC geared motor which I bought for an autoguiding project is too big as well. So, I went for the smallest one which sits inside the NGF-CM and it's about perfect! It sneaks into a corner without adding any weight and it does not protrude outside and thus it is very elegant. The pinion is too small for that bigger gear but I found it managed to drive it without major problem.

This is a wrong picture showing the RA rather than the DEC, but still it sounds like a promising project since the RA and DEC is basically identical for the TG-SP II.

Somehow I think that I will give up the autoguiding project since I lacked the proper skill to mount the motors perfectly. It could be done, but I guess it's less than ideal as autoguiding is concerned. And I guess that I ain't going to do very long focal length and that renders autoguiding an overkill.

BTW, if any one is interesting to pick up my autoguiding project, I can sell the parts to you and that includes two DC geared motor (5 RPM) with inline shaft couplings, a circuit board which can take ST4 guiding signal and to control the motors, a ST4 compatible socket so that you can plug your guiding camera to it, and finally, a prototype motor mounting board.

Thursday, May 28, 2009

Equipment cabinet

Just re-organized and tidy up the things inside. After selling my C5 and my Borg 45ED II, there're some more spaces but it's not well utilized and that's why I pulled most of the things out for re-structuring.

Many not always useful small parts were placed inside a box, and that frees up a lot of rooms. The frequently used items were placed inside another box. The solar filters are placed in corners so that they could be accessed fairly quickly.

A corner was allocated to my DSLR and lenses, previously they were here and there just to fill up any empty spaces (or gaps!) and now they have their corner. I guess that I will move more resources for photography than astronomy since it can be done far more often.

Finally, I'm wondering if I shall list out all those unused items so that I can sell them.

Wednesday, May 27, 2009

Goodbye my C5

Just sold my C5, including the focusing motor, the DIY controller box (it's my power box during the total eclipse trip!), the f/6.3 reducer and the 2" visual back. It's a kind of "romantic" to separate with it during a rainy night.

I guess the C5 would have a great new home! I can feel that the new owner is very much interested in astronomy! Glad that it will be gathering photon again actively than its life living with me.

I shall build myself another USB power box for my TG-SP II, since that box also helps me to re-charge my mobile phone during some special occasions. Maybe I shall add a few buttons there so that it can control DC geared motors, too.

Monday, May 25, 2009

The fully transformed Ranger

This is raining, was raining, and will probably continue to rain for a few more days at least, so it might be a good chance to report the detail of the fully transformed Ranger. I have been using it for some moments and it's just great! Optically, it's fantastic when used with a Solarmax, I used it frequently at f/60 and it's just perfect!

This is the focuser end. The original focuser is placed side by side for comparison. The NGF-CM allows manual focusing and it's even lighter in weight than a NGF-S due to the smaller motor. Of course, the NGF-CM or the NGF-S has far less travel when compared with the original focuser. But on the other hand, it allows more in-travel which is great when used with a focal reducer, etc.

The reason why I have replaced the focuser is for two reasons:

1. Motorized focusing, this is very important for H-alpha solar imaging due to poor day time seeing and the low contrast of the image.

2. 2" capability, this is great for wide field scanning. I'm having my Ranger upgraded to a poor man's Pronto.

After the transformation, I found that the weight of the whole scope is reduced a little bit. So, it's actually now a Pronto with the weight advantage of the Ranger.

The NGF-CM can be removed easily for a shorter OTA for transportation.

I can put it inside my Fast Pack 350!

A real nice project which makes my Ranger useful again! Whenever it's sunny, I will use it. And whenever I cannot bring anything bigger, I will use it. It's just perfect since I love my Ranger, it reminds me of great memories and it is now generating great images and even keep generating more great memories again!

Friday, May 22, 2009

Small DC Geared Motors

So last time I mentioned that I have two small motors and they looked very much like that from JMI, so here's a shot of them taken side by side. The JMI seems higher quality, but they're essentially the same. One of them is now mounted on my C5 OTA for motorized focusing.

Today, I took the other one out to see how I shall use it. Actually, I've two projects in mind:

1. Motorize the focuser of my Orion 100ED: this one is funny, since the original owner has a gear mounted on the focuser knob, that gear is from JMI but the motor has been broken, so I will only need to provide another motor with suitable mounting hardware, then it will work again. I would say that gear should mean 30% done if I go for this project. I guess if I have to use this long 100ED with my TG-SP II, I will want to motorize the focuser since this scope is going to be marginal for this little mount and thus a motorized focuser certainly helps.

2. Motorize the Tmax of my Solarmax 40: with a NGF-CM on my Ranger now, focusing is now a snap, but Tmax tuning is still now very great right now. If I can motorize the Tmax, the field will definitely be even more uniform than I can do now.

So, after some searching with the pile of "rubbish", I found a small motor box with wheels there, it is from a toy car. I tried to use the JMI controller on the motor, but it won't move unless I move the wheel a little bit, I guess the initial current is not big enough. And that motor is too fast for Tmax tuning. Anyway, the wheel seems useful since it has some rubber on it and thus, it can turn anything by friction!

I removed it from its shaft and found the hole a little bit too small for my motor, okay, it's easy to enlarge it. So I did it.

This is a protype mounting solution, and it works. With only a single rubber band, the balance is very poor, but then the motor can turn the Tmax easily right now. So my next target is to build a better mounting for it and then my solar image should improve!


BTW, those motors are available from ebay when you search for DC geared motor or something alike, they are available at a fraction of cost than the original, of course, you need to build your own mounting/adapters and it could be the hardest part.

Thursday, May 21, 2009

Good resources for DIY motors and gears

Check here:

So they support international shipping, and they allow small orders, and they have a wide range of accessories! Have a look if you're looking for something like focusing motors, gears, or something like that for your DIY projects.


On searching for a motor pinion for my 3mm small DC geared motor, I found this shop. The price of the motor is moderate at less than $2 USD each and the shipping charge is rather low at less than $6 USD. I have compared my own motor with the JMI motor from the NGF-CM, they might not be identical but they are 95% similar!

I will try to make a motor mount plate for my Orion 100ED, and if it's successful, I shall proceed to order that pinion gear!

Wednesday, May 20, 2009

My C5 OTA and accessories

These were posted for a potential buyer for my C5 OTA as well as related accessories. I hope these will show the condition of the C5, as well as its potential.

The red dot unit finder comes with it originally, and both end caps are included. A small dovetail is used for mounting to CG5/GP style GEM, alternatively, there are a few 1/4" thread holes on that dovetail so that you may mount it to good camera tripod.
The corrector is very clean since I rarely take it outside.

I have attached a focusing motor there. You can remove it easily, and no modification has been done to the OTA, no hole was drilled, everything intact.

To disengage the motor, simply take away that "rubber band" (that's not really a rubber band, but it is a special pully belt). This focusing motor is JMI or Meade compatible, you can even use a Shoestring FCUSB to remote control it via a computer, do autofocusing with any ASCOM compatible software.

This is a DIY motor controller box. It is powered by 4 AA rechargeables. Since it gives 4.8V DC which is very close to USB, so I have added a USB socket there. This socket was used to power my TG-SP II which requires 6V native, but I found 4.8V sufficient too. I even used this box to charge up my mobile phone via standard USB cable!

Here are the optional items. A f/6.3 reducer in near new condition, and a machined 2" visual back with two oversized locking knobs for heavy accessories. With the reducer, it becomes a highly portable 800mm focal length f/6.3 astrograph, or telephoto lens. Imagine how much it would cost for a 800mm f/5.6 prime lens ;-)

Okay, let's see some images taken with this small OTA, first up is Mars.

And then Jupiter.

Finally, another Jupiter.

These were taken with a DBK 21AF04.AS for the color shots and the monochromatic one is taken with a DMK 31AF03.AS... This C5 OTA changed my concept.... I previously think that we need at least 8 inch to do planet imaging, but as you can see, even C5 can produce something decent with newer technologies!

Monday, May 18, 2009

20090518 Sun

Sunshine again! Seeing 0/10 to 3/10, strong breeze is nice in terms of the hot weather, but it's not very much appreciated while you're imaging. Transparency is pretty nice at 5/10.

Tele Vue Ranger with 0.5x corrector for full disc shots, and then with Tele Vue 5x Powermate for close up. This time, I took that dying active region as well as a forming active region, as well as a nice prominence complex.

1407 (GMT+8):-

1408 (GMT+8):-

1413 (GMT+8), remnant of that active region:-

1414 (GMT+8), a developing active region:-

A nice and complex group of prominence, these were dim, I've to pushed exposure to 1/8s with very high gain:-

Sunday, May 17, 2009

20090517 Sun

It was cloudy yesterday, but the sky gets better today and we have a few cloud floating around. Seeing 4/10 to 1/10 due to some occassionally strong breeze, transparency low at 2-3/10.

Telescope: Tele Vue Ranger with NGF-CM
Camera: The Imaging Source DMK 31AF03
Filter: Coronado Solarmax 40 with BF10
Mount: Meade LXD55

1509 (GMT+8):-

1510 (GMT+8):-

I have used my Tele Vue 5x Powermate for close up, 1513 (GMT+8):-

Saturday, May 16, 2009

My hacked PST is up for sales!


The updated offering is $1450 shipped including a BF10, so that's what all you will need to use with your telescope for H-alpha solar imaging. If you don't want that BF10, $1000 will do.

It's a system that I have customed made with the help of a local friend. With much of the testing work, trial and error, it works nicely. However, due to my observation location, I couldn't use it for most of the time and thus this is up for sales.

Some samples shots:-

And how it is used with my C5. I've tested it from f/8 to f/10 and it works without problem. In particular, I've used it with a 70mm f/7.7 achromatic refractor, a 100mm ED f/9 refractor as well as a 127mm SCT at f/10.

So here is what's included in the deal, you can re-assemble it to form a PST as a portable setup. A bonus 52mm ERF will be included in the deal. Airmail shipping included for CONUS and for other places, please ask.

The etalon and the adapters side by side.

I would recommend this system as an *imaging* only system, since it might be harmful to your eyes. Take no risk in terms of safety!

New transformed Ranger and a DIY cable

So it's all ready! I've made a special cable from a useless headphone, notice that only one channel (two ear plugs) work with the JMI controller... You really got to check before the soldering work.

Notice that the wire from this headphone is a kind of crazy, it's a *single* coated wire only! But that's enough to drive the small focusing motor.

The original coiled cable is good, guess what I have to made this silly cable myself.

Yes, here's the answer, you see that the plug stand up quite high.

And this one is just far more low profile:

And only this one can clear the base of the mounting plate, the original cable is too high profile.

A tube ring is of course more desirable for the mounting both due to the balance and security, but then it also means extra cost and weight. I will settle for this solution right now.

Friday, May 15, 2009

Celestron CGE-Pro

Saw that from S&T recently, and I found this clip informative:

PS: I am not working for Celestron and I'm just a happy owner of a C5 OTA, and I've also owned and actively used a C8 for a few years.

20090515 Sun with a new focuser

Motorized focusing again! The NGF-S was gone and I have a NGF-CM now. Remote focusing would allow you to look very closely on the monitor, this improves the accuracy a lot. The lack of vibration during focusing is a huge plus especially when day time seeing is always confusing enough, so additional shake from hand is certainly a bad thing.

With the new focuser, I have far more in-travel (sometimes even too much that I have to go for extension tube), and that means I can use a 0.5x binoviewer corrector at the nosepiece of my BF10, this will allow me to take full disc shot without using drift and expand technique.

1519 (GMT+8):-

1521 (GMT+8):-

Next, a 2x barlows is used, extension tube is required:-

1523 (GMT+8):-

And then 3x, guess what, I've to try many combination in order to reach focus. NGF-CM is not designed as a single focuser, it should work with another rough focuser or else the travel will be very insufficient.

1540 (GMT+8):-

And finally even 5x, I even have to slide that BF10 from the draw tube a little bit and slide that 5x a little bit as well to reach focus:

1542 (GMT+8):-

1544 (GMT+8):-

Seeing 5/10, very good indeed. Transparency is low at 1/10, cloud moving around. AR1017 is dissolving, but I expect that it will still be there as some sort of remnant.

NGF-CM arrived

It's in great condition, near new basically.

The new controller provides variable speed and it's handy. The interface adapter is identical with the NGF-S and therefore, it mates with my Ranger adapter without problem. The 1/4" threaded hole on the base of NGF-S is gone, apparently due to the new location for the motor. Another hole was still around, since it's used to fix the focuser to the telescope interface adapter, and I just use that one to attach the scope to my mount. And it works great.

The motor engagement and disengaged mechanism is a kind of primitive but it works. That oversized knob is pretty troublesome and I expect that it would be broken during transportation. That motor is very familar in appearance, it looks exactly like another DC geared motor which I've acquired to motorize the focuser of my C5! No much complain here for the new motor, it's definitely smaller and there's no more big plastic cover to crack! That NGF-S cover is a kind of crack prone!

The profile of the NGF-S and the NGF-CM is virtually the same. NGF-CM has a brass compression ring, and it has a higher profile 1.25" adapter instead of a zero profile adapter. The manual focusing knobs are nice, easy to turn and accurate.

Overall, I'm very happy with this purchase. I shall take a picture or two later.


Additional Remarks from First Usage:

1. The new controller is excellent in terms of convenience, however, my feeling is that it runs faster than the NGF-S at slowest speed. Maybe I am wrong, but still, slight tappings could give me precise focusing movement.

2. The brass compression ring is not good, especially for that 1.25" adapter, it couldn't lock very tightly.

3. I have to DIY a new cable since the plug on the original cable is too long, older NGF-S cable has one side with a L-type plug which is more flexible.

4. I have removed that manual motor engagement screw, and instead, I used that allen screw for a more permenant engagement for I will use the motor for most, if not all, of the time. Of course, if I were to go out for visual observation, I will use that manual screw.

Thursday, May 14, 2009

20090514 Sun (AR1017 is getting weaker)

- Tele Vue Ranger
- Solarmax 40 with BF10
- DMK 31AF03
- Extension platform plate on LXD55
- Seeing 3/10, transparency 2/10, cloud moving around

1457 (GMT+8):-

1459 (GMT+8), close up with 2x barlows, 1017 is getting weaker it seems:-

Wednesday, May 13, 2009

20090513 Sun

Following that active complex... it's still going strong today, seeing 3/10, transparency 2/10. Again using my Tele Vue Ranger with Coronado Solarmax 40 and BF10, DMK 31AF03 with LXD55.

Full disc b/w 1514 (GMT+8):-

Closeup with 2x at 1517 (GMT+8):-

Closeup with 2x at 1521 (GMT+8):-