20090512 Saturn

This is another test of my Orion 100ED, the focuser after tuning is much better, it's just smooth and accurate, and it holds heavier stuff than before!

This is taken with a 3x barlows and DMK 31AF03:



I've pulled out my 7mm Ortho to have a look, the color variation on the globe is very easy to see, and it's just sharp! Now I know why 4" refractor is so common because it's simply a great tool for visual observation.
Seeing is no good, I guess around 3/10, transparency like 2/10... I've to use 1/8s exposure with very high gain.

20090512 Sun with lots of activities!

Two groups of interesting prominences, and a huge complex of active region, what else can you ask for during this solar minimum?

Seeing 3/10, transparency 2/10, thin cloud is always here and there, so the exposure has to be pushed up.

Tele Vue Ranger with Solarmax 40 and BF10, DMK 31AF03, LXD55 with a long platform plate to reach outside.

This full disc shot is again suffering from cloud since it's taken with drifting expand method:-

So this one is taken with two separate AVIs and stitched together:-

Close up of the active complex:-

Close up of a prominence:-

Close up of another prominence:-

Motorizing the Tmax of my Solarmax 40

Suddenly got this idea, and I guess it will not be too hard to execute since the adjustment knob is pretty easy to turn, and therefore, frictional drive should work and no gear matching job will be required.

After motorizing the focuser of my C5, I still have another small motor left and I guess that I could use that one. Time to try it out!

Everything originated from the fact that I'm now using my Ranger again, since it's longer and adjusting the Tmax becomes a little bit harder than before when I was using a tiny Borg 45ED II. A great Tmax position could really affect that imaging result.

Small Saturn 20090511

Tele Vue Ranger, 5x Powermate, DMK 31AF03, 7.5fps, 1/8s exposure, very high gain...



It's pretty dim in the DMK, but with a 20mm Widescan III + 5x barlows, it's not bad at 120x visually. A nice view indeed, my wife had a look too.

20090511 Sun with a big active region

Seeing 3/10, transparency 5/10, Tele Vue Ranger, DMK 31AF03, Meade LXD55, Solarmax 40 with BF10, 2x barlows and 5x Powermate.

1430 (GMT+8), when thin cloud are moving around, the drifting expand method could fail very badly, this is a good demonstration:-


1433 (GMT+8), at f/24 (i.e. with 2x barlows):-


1447 (GMT+8), at f/24 (i.e. with 2x barlows):-


1454 (GMT+8), at f/60 (i.e. with 5x powermate):-


Visual view with a 20mm Widescan III is quite nice, that filament is pretty contrasty, but the active region is rather subtle.

Too bad that I couldn't use my C5/PST.... I should find a way to use it.

T-mount and M42 mount

T-mount is M42, but the thread pitch is 0.75mm

M42 mount is also M42, but the thread pitch is 1mm

So, they're not exactly compatible, just a note.

20090508 Sun

I have fine tuned the helical focuser of the Ranger and it now works perfectly, feel like cutting through butter. The platform plate works very well now and the stability is great, it reached out far enough for the summer days to come, good!

So the seeing improved a lot today, I would rate it a solid 5/10 today, and the transparency dropped a little bit, still good at 4/10. We don't have this kind of sky usually, and the weather feels like Fall, dry air and with soft to strong breeze, very comfortable.

My Tele Vue Ranger was used with a Solarmax 40 with BF10, DMK 31AF03 was used for capturing, everything all a LXD55. That platform plate is a long 6061 0.5cm plate which has a Intes dovetail mounted below, with a Manfrotto 410 geared head mount above to connect to the Ranger, a small counter weight has to be attached for balance in RA, it's totally out of balance in DEC but there's no problem for the LXD55.

1515 (GMT+8):-


I pulled out my eyepiece to have a look and I saw a nice prominence, so I put in my DMK there again to capture.

1521 (GMT+8):-


1524 (GMT+8), with 2x barlows:-


Unluckily, I couldn't use my C5/PST in this season...

20090507 Sun

Today I setup my platform plate in order to reach for the sun from inside my home, stability is less compromised than the setup last year. I did it because my very light weight Borg 45ED II was sold, the Ranger is heavier and thus requires a better setup. This actually improves the image as a side effect, not bad.

Seeing is very poor at 1/10, transparency similar to yesterday at 5/10, it feels like Fall here. Surface activity remains low, but there're two nice prominences. I even had a quick look with a 13mm Nagler Type 6, and it's just amazing. Filter is Solarmax 40 with BF10, camera is DMK 31AF03.

1446 (GMT+8), due to the poor seeing especially near the bottom of this image, so it's less stacked below and thus I've to resize to hide the noise, but it's still there.


With 2x barlows, 1509 (GMT+8), poor seeing hides all the detail:


1510 (GMT+8), also with 2x barlows, poor seeing persists:


--

Since I've fixed the draw tube of the Ranger last night, today I tried to fix the helical focuser as well. It's getting stiff at some point, I disassembled it, clean all the dirt and re-grease the whole thing, I also carefully adjusted the friction on the retaining ring so that it's now better. I suspect the plastic rings were misplaced last time, so I swapped them and it works better.

Feels like cutting through butter now!

Focuser for the Ranger

With the departure of my NGF-S, I have to use the original focuser of the Ranger for the time being. I found that the last time I removed the draw tube, it's not in optimal condition now. So, I disassembled the whole thing tonight to try to fix it. I tried various method to insert that stopping pin which guides the draw tube, and I guess I finally know how to put it back in the right way. I have to slide the draw tube all the way until the slot becomes a narrow slot so that the stopping pin can stand up by itself, by then I should fix that screw for that hole... Turn it all the way in until the draw tube was locked by that stopping pin, and from that point, losen that screw very little, actually, as little as possible so that the draw tube is now movable but the pin was still restricted by that screw.

I tried many times to do that, and practice make perfect! Now, it's in great shape.

--

I have just found a NGF-CM in astromart, and payment was sent on the same day which I shipped my NGF-S. The NGF-CM can be used manually and both motorized, so I guess it's even better for visual observation, the motor in this version is far more compact and easily to bring outside. It should be slightly lighter as well as I read from the net.

Only NGF-S has a 1/4" threaded hole on the base, but the NGF-CM should still have another threaded hole that could be used for mounting, otherwise, I will have to think of other mounting solution for my transformed Ranger.

My Ranger will have a new focuser very soon, and solar imaging will become more effective than now. But at the time being, the fixed original focuser should work out well, too.

The NGF-CM is coming from Singapore this time, and thus it should be faster than from the US hopefully.... I just wish that it could come next week.

Saturn!!!

Didn't see or capture Saturn for one year or maybe two years! This time, I am using my Orion 100ED f/9, it's definitely non-stellar with a 40mm Pentax XL, and switching to a 13mm Nagler Type 6 revealed its ring. The ring is closing but it's very contrasty still. Adding a 2x barlows does help to show more detail. Finally, I switched to a 7mm Ortho and it gives the best view, the subtle color variation on the globe is quite apparent. No color error for all magnifications that I tried, it's definitely a great scope!

On defocusing, it shows that at least 20-30% of aperture is blocked by the window frame or the wall, but anyway, it's good enough. I pulled out my DMK and the effect for the partial aperture blocking is now more pronounced since the image is dim even at f/18, I have to go down to 1/8s exposure with medium gain, or 1/15s with high gain.

2340 (GMT+8), slower shutter, low gain:-


2343 (GMT+8), faster shutter, higher gain:-

20090506 Sun

Seing 3/10, transparency like 5/10, Tele Vue Ranger with original focuser, Solarmax 40 with BF10, DMK 31AF03 on LXD55.

I'm still trying out that drifting method, but then the seeing was no good, and so some frames were dropped and thus upon stacking, part of the solar disc could be missing, or with very high noise.

1604 (GMT+8), resized to hide the noisy part:-


1605 (GMT+8), that prominence:-


1608 (GMT+8), 2x Barlows added:-

Packing my Borg 45ED II with NGF-S

It's ready for shipping to the new owner. I placed the Borg 45ED II objective and the draw tube into the original box, bubble wrapped. The cable for the NGF-S was placed inside as well.


Next, the Borg #7508 adapter (2" visual back) was screwed together with the NGF-S adapter. One will need to connect that #7508 to the Borg OTA via the male thread (M57P0.75). The adapter on the right is from the NGF-S, and it is used to connect the NGF-S to standard SCT rear port thread, so if one want to use the NGF-S with a SCT, you will need this adapter.


The above two adapters were wrapped and packed inside another Borg paper box. This is not the original box for these adapters, but I found it handy and the adapters fit well there.

These two screws are removed from the NGF-S, I packed them separated since they're pretty long and could be bended seriously during transportation. However, since they're pretty small, please make sure that they will not be thrown away when buried in the pile of packing materials. I stucked this little plastic bag inside the focuser draw tube.

So, all the boxes are placed inside another box. This is the view before those peanuts were stuff'ed in. The longer Borg box contains the Borg 45ED II OTA together with the NGF-S controller cable. The small white pack on the right of it contains the NGF-S hand controller, there is a 9V battery inside but it's pretty old, I guess it can still run the focuser for several hours, but in case you need to replace it, feel free to open the box.

The smaller Borg box contains the adapters above, finally, the bubble wrapped thing on the left of it is the NGF-S with the set screws sneaked inside the draw tube.


Finally, I wrapped the whole box for elegancy. :-) The scissors is for demonstration only, it gives a rough idea about the size of the box.

Mailing address has been printed and sticked to the top and bottom of the box to make sure that in case one of them got detached accidentally, there's another one.

Good bye my lovely Borg 45ED II with NGF-S, it has been with me to my first total solar eclipse trip, and to other dark places in the world, it also spent many afternoon with me for solar imaging with my Solarmax 40/BF10. I wish it all the best and I believe that it's going to perform well for the years to come!

Orion 100ED and the moon

Got the moon outside in good place, so my Orion 100ED could be pointed to it from indoor, seeing very poor at 2/10, transparency pretty high today at 5/10.

First up is my Pentax 40mm XL, very sharp, no color at the limb in focus, very nice view indeed! Highly contrasty and sharp!

Next is my Nagler 13mm Type 6, again, very sharp. The moon nearly fill in the whole 82 degrees field of view! Again, no color around the limb.

Placing my 5x Powermate in between, the image becomes much dimmer, but it's still okay, no color still. It's about afocal, but you would want to tweak a little bit.

How much magnification that I'm using... let's see... 900*5/13 = 346x!!!

This is a really good telescope! Now, I know that I have got a really good deal!!!!! FPL-53 is not a joke especially at f/9! It's really a poor man's true APO!

20090505 Sun

I fall back to use my Ranger with its original focuser. The 0.5x corrector could no longer be used in the nosepiece of BF10 due to the reduced in-travel, but I placed it on the nosepiece of the DMK at least, I guess the reduction factor is very little, but it's better than absence.

No more motorized focusing, the focus position is less than perfect, but it's acceptable, not too far from the correct position. With a f/12 light cone, you really couldn't go too wrong.

Seeing 3/10, transparency 6/10. Since the corrector is acting in a less powerful way, I have to use "drift method" during capturing and "expand to maximum image size" in registax stack to get full disc. The result is not bad as I can see from the raw.

This is the first attempt at 1519 (GMT+8), notice that the field is not very even, since I stay too much time on the upper part and it's not averaged enough so the sweet spot was shown:-



This is the second attempt, I start drifting the image from the chip as soon as the capturing begins, so the field is surprising uniform, but I didn't stay long enough for the lower part and therefore, the amount of noise is more there.



I shall write a separate article on this interesting technique. This is good in the sense that:

1. Uneven field illumination/bandpass will be averaged out
2. Dust on the chip will be averaged out
3. We have an effectively bigger image area, no need to do mosaic

I shall improve this skill further!

Say goodbye to my NGF-S

Originally, I only plan to sell my Borg 45ED II, but the potential buyer wanted to have a focuser, so I guess I can let him to take it first and then I buy another one later. Somehow I prefer to have a focuser which is both motorized and manual focusable, so now I'm open for other options now.

I placed the original Ranger rear assembly back now, and I just took two solar shots with it again :-)

I guess a NGF-CM should fit my purpose, and if you have one, let me know.

--

I have a sudden thought about buying a focuser which can be shared between my Orion 100ED as well as my Ranger, but such idea is not feasible indeed since the Ranger has little back focus and thus I need a low profile focuser but then it's not going to work with the 100ED.

20090502 Moon

The moon is in the right position to observe, it's not low enough for me to use my 100ED, but the Ranger is definitely fine. Seeing 3/10, transparency 4/10. Taken with my DMK 31AF03 at prime focus of the Ranger.

2141 (GMT+8):-


So many birds tonight, two of the most representative ones:

20090502 Sun

The test of my transformed Ranger continued. Tele Vue Ranger with 0.5x binoviewer corrector at the nosepiece of BF10, Solarmax 40 in the front.

Seeing 4/10, transparency 4/10.

1352 (GMT+8):-


1353 (GMT+8):-


Not bad, as least nothing worse when compared with the former Borg 45ED II based images.

Finally, Tele Vue Ranger at prime focus, i.e. the same as above without the 0.5x, drifted during exposure and registax'ed to yield full disc by expand to maximum image size.

1356 (GMT+8):-


This time, the Tmax is less than ideal... should try more.

20090501 Sun (Ranger)

First light of my transformed Ranger! At prime focus, the image quality is excellent, nothing worse than my Borg 45ED II. Full disc imaging is harder, that 0.5x corrector is not powerful enough if placed in front of the C mount adapter, but it's too powerful if an filter thread extension tube is added so that there is insufficient in-travel. However, it works perfectly when the corrector is placed in front of the BF10! Therefore, I can do full disc shot as easy as before.

My LXD55 is powerful enough to carry it even if not fully balanced due to the extension plate added to make it closer to the window frame. Therefore, the Borg 45ED II could be replaced totally.

Two shots at prime focus merged, 1415 (GMT+8):-


Taken with 0.5x corrector, the focus should be wrong, I should be more patient next time, but at least it shows that it could reach focus and it could take the full disc at once, 1425 and 1426 (GMT+8) respectively:-

Tele Vue Ranger transformed

The focusers side by side, they're with similar length. The JMI has much shorter travel due to the lack of that sliding draw tube, the fine focusing range is not differ by much. However, you can remove that extension tube (1.5" long) for more in-travel for the NGF-S.



This is the custom made adapter, with perhaps 1-2mm more female thread, it will look better. Anyway, it works.



Focuser attached, very elegant and the Ranger has a new life. Shall I call it a Pro-ger?


Last night, I tried to put my 2" mirror diagonal there, and as expected, with the extension tube of the NGF-S, it couldn't reach focus, I've to slide the diagonal a little bit outside. With the extension tube in place, it could not too. Anyway, it's my design since I wanted to retain the most in-travel. By keeping the diagonal a little bit out from completely flushed in, it's secure enough. All of my eyepieces and barlows work in this way, slide out a little bit and that's it. Maybe a 2" filter thread extension tube would serve as a more elegant draw tube for quick focusing, but it's all later work.

The transformed OTA is shorter than before, and a little bit more heavy as expected. The focuser could be easily removed and re-orientated. That would enable it to sneak into my Fast Pack 350 without problem. Excellent portability.

Tomorrow if the weather allows, I shall try to use it on the sun with my Solarmax 40/BF10, that's going to replace my Borg 45ED II and I shall also try it out with a 0.5x binoviewer corrector.

--

So before the sunshine comes, I try to put everything together and point it to terrestial target to test the focus travel:-

Attaching a small EQ mount on the window frame?

I have always been thinking how to put my mount closer to the window, the closer my mount to the window, the more field of view that I got get. A pier should be perfect, but such a small pier might need tailor making and it would become very expensive.

Today, I saw a few screw holes on the window frame, so I wonder if I could attach a small EQ mount there? Let say my Takahashi TG-SP II, it's small but it's powerful enough even to hold my C5, and yesterday night, I actually tried to put that Orion 100ED OTA there and it works. Frankly, the C5 is like 6lb and the Orion is like 7lb only but it's longer, so it's not too surprising to see that it works.

Therefore, I shall see if I can find suitable mounting hardware when I got more time. At the first glance, it should be feasible.