Wednesday, January 23, 2019

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.

Friday, January 11, 2019

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!

Friday, January 04, 2019

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.