mercury transit 2019

11 Nov.

Ah well, high haze gave way to cloud with not a single clear patch through to sunset.

Here we are about 20 minutes in:

Just in case you don't believe me, here's detail from about the 11 o'clock position...

...a few moments later, the haze eased a bit...



new clusters

To me that is. Also gives an idea as to the difference in seeing and therefore effectiveness of guiding on two consecutive nights. I tried to keep the processing the same on each.

Also a chance to debug the latest zwo SDK native and with the INDI driver under phd2, the latter looking good so far.

And, try out Siril's photometric star colour calibration.

distance: 3700 ly RMS 0.8
open cluster ngc559 in cassiopeia
700d on nt150s    37x240s @ ISO800

distance: 3900 ly RMS1.9
open cluster ngc744 in perseus
700d on nt150s    34x240s @ ISO800


phd2 build and debug

ubuntu build

Big thanks to Andy and Patrick over on the phd2 list for these details and for putting up with my constant noise.

sudo apt-get install build-essential git cmake pkg-config libwxgtk3.0-dev \
wx-common wx3.0-i18n libindi-dev libnova-dev gettext zlib1g-dev libx11-dev \

Get the PHD2 sources
git clone https://github.com/OpenPHDGuiding/phd2.git
cd phd2

Generate the Makefiles
mkdir -p tmp
cd tmp
cmake ..

Build PHD2
Once PHD2 is built, you can either run PHD2 from the local build directory:

or install PHD2 onto the system:
sudo make install

upgrade the SDK in your build
download the sdk from here: https://astronomy-imaging-camera.com/software-drivers (section: for developers e.g. ASI_linux_mac_SDK_V1.14.0715.tar.bz2)
unpack the SDK
/path/to/phd2/build/unpack_zwo_libs ~/Downloads/ASI_linux_mac_SDK_V1.14.0715.tar.bz2
rebuild phd2
(note that unpack_zwo_libs is a script which extracts the SDK into the proper directories for you)
make -C /path/to/phd2/tmp
run phd2 
(confirm the SDK version in the debug log, look for "ZWO: SDK Version = ")

To debug a crash run phd2 under gdb.
phd2 needs to be built with debugging symbols:
When you are at the cmake step do: cmake -DCMAKE_BUILD_TYPE=Debug ..
Then: make

to debug: gdb ./phd2.bin
you should see a line : Reading symbols from ./phd2.bin...
from with gdb then type

After a crash
gives the backtrace

does what it says
you will need to present the core file and the file phd2.bin to the developers


A wide view in the blustery conditions of the approaching cold front last night...
open clusters ngc457 owl and ngc436 in cassiopeia
700d + 0.9cc on 130pds    31x240s @ ISO800


ngc 7790

Nice and clear with moon-set around 23:00, but with wobbly seeing and FWHM around 6.0? Not good. Add to that, the cheepo 0.9cc to make matters worse. Anyway, looks like a candidate for something a bit more powerful; another double cluster. 7790 at 10000 light years and 7788 a bit closer.
open clusters ngc7790 centre and ngc7788 in cassiopeia
700d on 130p 585mm f4.5    34x240s @ ISO800


andromeda revisit 4

The previous visits have been with various telescopes of vastly varying quality. This year it was the turn of the €200 SkyWatcher 130p with the cheepo 0.9x coma corrector to give 585mm fl. Still not able to fit in the whole galaxy.

The other reto being to automatically get 72 frames with me doing something else other than sitting next to a telescope taking photos. All went well up until the meridian flip at 23:14. It flipped fine and began imaging. Alas, it didn't restart the guiding. So almost 72 frames without human intervention.

l to r galaxies m31, m32 and m110 in andromeda
700d on 130pds    72x300s @ ISO800