20190207 DSLR Sun

1142 (UT), taken with Canon 450D (low pass removed), Solarmax 60/BF10, Tele Vue Ranger at prime focus, auto level stretched.

20190123 Sun

Got a break today, took a short video clip.  Not featureless, but still silent.

0645 (UT)

20190122-0123 水浪窩 Camping

I am trying out my new ultra-light gear.  Everything packed and it was less than 8kg including my Canon 450D modified with my new Canon 24mm STM.  I really love this new backpack for ultra-light trips.

Bu then I forgot that regular camera lens won't come to infinity focus after removing the low pass filter, last time I made the same mistake in Chek King (赤徑) and life has to repeat the same failure. 

Given the failure last time, I didn't realize that until after several shots.  To solve the problem, I found that EF lens could reach infinity focus with a CLS filter installed in front of the CMOS, but then EF-S lens was not compatible with the drop-in CLS filter.  So, I'll have to come back to EF lenses.

It was Tuesday night, but we still got two other groups around.  One was a family, they even setup a campfire, singing some Christian hymns with guitar.  I went to the other side of the wind in order to get rid of the smoke.

My minimalist setup, but yet still quite comfortable, for I've a carbon fiber foldable camp chair.

Here are the out of focus shots before bright moon light comes!  By then, I didn't even need a flashlight to move around the campsite.  I even have to use eye patch to sleep inside the tent.  Temperature was below 10 degree Celsius, but I forgot to bring my thermometer to tell the actual reading.  Wind kept sneaking into my tent, moving the inner mesh wall.

I got only a small tripod.

I shall try to make some star trails next time if the sky was not great, and then I shall try to bring a tracking mount when the sky might be better.  This is not a perfect site for astrophotography, but then it's reachable to me easily.

After maybe around two hours, I went to sleep.  Breakfast time on the next morning!

On the way leaving the site, I found the grass land besides the helicopter pad could be a good spot for imaging.

We should stay outside the landing pad, in order not to hinder any emergency mission.

For ultra-portable setup, I shall use a fixed short tripod.

For tracked imaging, I shall use a taller tripod, in order to do the polar alignment.

20190111 Sun

This is the first imaging session for 2019!

First up is a full disc shot at 0721 (UT), foggy sky but rather nice seeing.  The solar surface remains inactive, note the bigger prominence on the 9 O'Clock position.

Close up at 0726 (UT), higher gain faster shutter, higher fps as a result:

Another close up at 0729 (UT), lower gain slower shutter, lower fps as a result, but less noise:

For better seeing, we don't need high fps or faster shutter to freeze seeing... slower shutter and lower gain means less noise!

Canon 24mm f2.8 STM and Canon 10-22mm f3.5-4.5 USM

Since I've started some simple astrophotography during my camping trips, I gathered enough reason to re-organized my lens line-up finally.

What was missing from my collection is a really wide angle lens.  I have been using a 8mm f3.5 manual fisheye lens for that purpose before, but then it has limited usage during day time, and it is a little bit too wide if I have only one lens.  You took a few shots and those will cover the whole sky!

Therefore, a 10-22mm or a 10-18mm is always in the wanted list.  Today, I get a great 2nd hand deal on a Canon 10-22mm, the lens is aged but it works.

And for ultimate portability, I got another nice deal of a brand new pancake Canon 24mm f2.8 lens a couple of days ago, too!

Vignetting is rather heavy if it was used wide open, but for the price, its size and weight, it is a must have other than my existing 50mm f1.8 lens.

Let's see how they work out.

20181226 Sun

0827 (UT), the solar surface remains boring, except a small active region on the upper right, and a few small prominences.

Ranger with Solarmax II 60 with BF10, with the reducer on.

Chuwi Lapbook 14.1

I've a cheap Chuwi Lapbook 14.1 laying around and it could be used for astronomy purpose.  The first thing I will need to do, is to expand its storage, so that it could store more images or even video from Sharpcap.  This is only possible with the earliest version of the model which comes with a m.2 slot, later versions have it removed silently.  On simple disassembly, I found that I am lucky enough to have the original version!

I got a really cheap one from taobao, and it has 128G in size, which is about right in terms of price and size!  It makes no sense to buy something expensive for a cheap notebook!  128G will triple the original size!  This SSD has a form factor of 2242, but it also comes with two detachable parts for better compatibility with bigger form factors.

Windows managed to detect the SSD without problem, and after simple partitioning and formatting, it's ready for use.

A quick speed test was conducted in Sharpcap, it's way faster than the original internal SanDisk eMMC!

In addition to my Voyo, this Chuwi could be used as well.  I suspect it will yield higher fps than the Voyo which features a faster CPU.

20181213 水浪窩 雙子座流星雨?

其實未出去已經知無景，不過算係去散吓心。

雲不散，不概嘆，早已慣；早一晚，藏山間，靜無限。

Canon 450D modified, 20s exposure at ISO 800, fixed tripod.

Minimalist style camping, less than 9.2kg total.

20181129-1130 Modified Canon 450D first light (Camping in Chek King)

I went for a camping trip and astrophotography was only a very small part, so I used a mini-tripod with a small ball head only, and I only had my Canon 50mm f1.8 with the modified 450D.

To keep the story short, I found that the 50mm f1.8 could no longer reach infinity focus when the IR filter is removed!  The 50mm f1.8 has very limited focus travel, and this is the problem.  Notice that it's not autofocus that fails, this is anticipated due to the change of the optical path length.

It's one of the best night for the last decade, luckily I've my Canon 10x30 IS with me and I enjoyed tremendously!

Sirius with M41, I love to catch the view when it's still low in the sky, the tree as foreground is very nice!

M31 at the corner.

M45 hanging just above the trees.

The Orion and M42 just went above the tree!  Note that red color on M42, it used to be purple before.

Later I found that if I insert a CLS filter between the lens and the camera, it will reach infinity focus again!  Next time I shall try this one combination out.

For wide field, maybe my Canon 70D is better due to the movable LCD, composition should be far easier.  The modified 450D might be better for targets richer in H-alpha.

20181111 Sun

The sun surface is still quiet, 0653 (UT), taken with reducer on:

But on carefully second look, you could see two small prominence at the 1 O'Clock and 7 O'Clock direction.

So here are two shots with 5x Powermate, and reducer removed.

First at 0701 (UT):-

And then second at 0706 (UT):-

The Solarmax is not very good at imaging these.

Canon 450D modifications

Canon 450D is my first DSLR.  But after I got my 70D, this was left idle.  I always want to remove its IR filter astronomy purpose, but I never got the time and courage to do that.

As the price of 2nd hand 450D is dropping, the initiative is getting bigger and bigger.  In order to unleash its residue value, the modification is the only way to go.  Earlier this morning, I took the plunge to carry on the modification according to the information on the web.

However, those pages were updated as newer DSLR comes into the market, and thus some photographs along with the instruction might not be very helpful.  Some guess work required.

The most difficult trouble to me was those screws.  I simply couldn't remove a few of those screws, they literally screwed up!  I had to use a drill to remove them completely in an irreversible manner.  I met maybe four such nasty screws.

Here are some snapshots, the first milestone as below with bottom and back cover removed:

Next, when the daughter board was removed:

And then the metalic cover on top of the CMOS assembly:

And then the CMOS assembly:

The shutter could be seen above, and the CMOS board below.  A cutter has to be used to remove the first filter.  The first filter serves as the dust removal system and this was to be kept.  The second filter was the one to be removed.  And below that was the CMOS.

I did removed the filter, but I didn't take any photograph of it.  I placed it downward to prevent dust from falling onto it.

Re-assembly is easier but still quite difficult.  I managed to leave a few screws unused, but then the camera works without problem, no loose parts.

This is the first shot taken after the modification!  The pinkish hue is so lovely!

Finally, I had set the internal parameter for astronomy purpose.  Turn on RAW mode, remove any built-in noise reduction, turned off the flash by default and so forth.  Wish to use it in the field soon!  Together with the DIY external power supply, this is going to be my work horse under starry sky!

20181105 0644 (UT) Sun

As title, the sun is still very inactive with a dim filament on the upper right, and it seems to extend to the limb as a small prominence.

20181029 Sun

The sun comes back to my observing windows! 

But it's solar minimum, dead silent.

Taken at 0553 (UT), Ranger with reducer, Solarmax 60 with BF10, ASI 120mm.

I've tried to push up the image scale with 5x Powermate, but again nothing except a few interesting magnetic pattern.

20181027 Mars

The Mars is getting farther, dimmer and also smaller.

Pulled out my 85mm ED refractor, and 5x Powermate, ASI 120mc.

This time I reduced the ROI to 640x480 and the frame rate goes over 38fps!  Very nice indeed!

The Nexstar mount is very stable now, vibration damps out very quickly and I don't need electronic focuser any more!

Taken at 1410 (UT), 1.5x Drizzle.

20181007-1008 Camping and wide field imaging

Camping means heavy gear, you have a tent, cooking stuff, sleeping stuff, food, water, etc.

Stargazing is never light weight as well.

But I'm trying to combine these two, and I don't have a car.  I've to rely on public transportation which means very limited access both in terms of location and time - the last bus could be as early as 21:00 so that I won't have much time to observe if I had to go home.  So, it would be nice to stay overnight.

This time, I choose Shui Long Wo (水浪窩), which has better access, the last bus would be 00:00 so that I could go even after dinning with my family.  With heavier gear, the location could be reached in less than 20 minutes walk.

Water source is not too far away, but the supply could be unstable.  The toilet on the roadside could easily ran out of water due to the heavy usage from the nearby BBQ sites.  There is another water source up there in the middle of the way to the campsite, but this one could go out of order as well.

Since this is just a test of the concept trip, I brought only a DSLR with a fisheye lens on a camera tripod.  I've 15kg of stuff together with 5kg of water acquired in the middle of the road.  I believe I could further trim down the weight by 2-3kg.

The first one was taken before midnight at around 22:30, light pollution was serious.

The second one was taken around 3:00am, the dark was darker.

No more than 20s exposure could be used, or else the screen would be saturated.

It would be a bit too soon to conclude that this site is no good, since you could thin from the above that a thin layer of cloud/mist was there.

20181005 Sun

Solar minimum that it!

Half day off today, so I pulled out my Ranger with Solarmax 60 and BF10 for a short imaging session:

0542 (UT), with reducer, taken with ASI 120mm

Only a very thin filament could be seen.

I've fully enhanced my Nexstar mount so that now it has a longer controller cable, no more shake induced by the short coiled cable!  Also, I've added three very large rubber padding to reduce the vibration and they're oversized for better stability.

20180921 Observation with Almy

I pulled out my 85ED when I saw the Mars and the moon hanging outside my windows.

I looked at the Mars with my 4mm TMB, and then I turned to the moon.

Took a couple of images, and then I called my younger daughter Almy me.  She enjoys the view through the eyepiece and she even took some afocal snapshots with her mobile phone.

All the images below were taken with my ASI 120mc, yes I was too lazy to switch back to the 120mm after imaging the Mars.

1538 (UT), processed with drizzle 1.5x:-

It is getting farther away and thus smaller...

1542 (UT):-

1543 (UT):-

1545 (UT):-

20180902 Mars

1554, (UT), 85ED with 5x Powermate Drizzle 1.5x, ASI 120mm.

It was amber rainstorm this morning, but it's quite clear tonight.  Seeing very poor and I could see a shaky image even at very low power.

The Martian dust storm seems cleared up, maybe the best image taken this apparition for me.

I has been fine tuning my Nexstar mount, a circular wooden base was added for better balance, preventing tip over.  The controller cable was made longer so that the shake from the cable won't induce vibration to the mount now.  The base was still unstable, and I placed an eyepiece cover below to stop the vibration, since I've only four small pads below.  Some more would be added shortly.