Thursday, 9 April 2020

Further testing of DSLR Live-View with USB tethered cameras in AstroDMx Capture

Last night we were testing the properties of the Live-View controls in AstroDMx Capture, using a Windows 10 computer.

A Canon EOS 4000D DSLR was placed at the Cassegrain focus of a Skymax 127 Maksutov. AstroDMx Capture for Windows was used to control the camera and to capture data.

The Equipment setup


The whole purpose of Live-View for astronomical imaging is to facilitate rapid focusing and correct positioning of the object in the field of view. Once an apparent good focus has been achieved, the camera can be set into a loop where images are displayed in quick succession and by setting the displayed image to a large percentage of its maximum resolution, the focus can be refined if necessary. When the image is focussed, images can be captured.

In this experiment, the camera was set to maximum resolution fine JPEG mode. This puts the camera into 8-bit mode. The property of the Live-View controls being studied was the ability to change the exposure and ISO while Live-View is taking place. It is important to do testing on real Astronomical objects in addition to considerable bench-testing, in order to see the effects of changing the controls in various combinations dictated by the imaging session. These tests provided information that has allowed Nicola to make code changes that produce more efficient operation and stability.

The camera was set to capture Tiff files, which in this case were 8-bit tiffs. There is little point in using 16-bit while capturing a bright subject such as the Moon. AstroDMx Capture for Windows was used to capture 100 images.

AstroDMx Capture for Windows capturing 8-bit Tiff files


The images were stacked in Autostakkert! 3.10, wavelet processed in Registax 5.1 and post processed in The Gimp 2.10.

Lunar image

The additional control available in Live-View will have to be extensively tested with both Canon and Nikon cameras. Not all camera manufacturers support USB tethering, and those that do, don’t necessarily support all cameras, Live-View, or all controls. This evening’s work was another step along the journey to a release of a version of AstroDMx Capture with DSLR Live-View.

Tuesday, 7 April 2020

32-bit Linux support and also DSLR live view for AstroDMx Capture.

Although there is diminishing support for 32-bit among Linux distributions, there are still a lot of reasonable spec 32-bit laptops out there that could become useful imaging machines. Moreover, there are still 32-bit Windows 10 netbooks that are low spec devices that struggle to have enough resources to even update Windows.

Although not straightforward, we have installed 32-bit Debian on our Asus EeeBook

Nicola has compiled a 32-bit version of AstroDMx Capture for Linux.
The 32-bit version of AstroDMx Capture for Linux saw first light by imaging the 97.6% waxing, gibbous Moon.
A QHY 5L-II-M camera was placed at the Cassegrain focus of a Skymax 127 Maksutov and the 32-bit version of AstroDMx Capture for Linux was used to capture 2,500-frame SER files of two overlapping regions of the Moon in the Copernicus, Kepler, Reiner Gamma region.

The imaging setup

Screenshot of the 32-bit version of AstroDMx Capture for Linux capturing Lunar data

The best 75% of the frames in each SER file were stacked in Autostakkert!, wavelet processed in Registax 6, and post processed in The Gimp 2.10. Microsoft ICE was used to stitch the two resulting images into a two-pane mosaic.

Two-pain mosaic of the Copernicus, Kepler, Reiner Gamma region

Closer view

It is hoped that the 32-bit version of AstroDMx Capture for Linux will give a new lease of life to older or low spec newer laptops and netbooks as Linux imaging machines.


DSLR Live-View

Nicola has also implemented Live View for supported DSLRs. It should be noted that Live View is not a high-resolution view and the actual resolution is camera specific, with a maximum of full HR resolution. However, Live View can be used as an initial focusing aid before putting the software into the DSLR Loop function to repeatedly show preview images at high resolution to refine the focus, before stopping the Loop and starting the capture of images.

The Live-view functions were tested in AstroDMx Capture for Windows but will be present on all platforms. This is quite an exciting implementation as it provides more functionality than is normally found in Live-View. This will be reported on when the implementation is complete.

A Canon EOS 4000D DSLR was placed at the Cassegrain focus of a Skymax 127 Maksutov and the camera was tethered to a Windows 10 laptop running AstroDMx Capture for Windows.

The imaging setup

Screenshot of AstroDMx for Windows showing Live-View

Closer view

The image can be scaled as usual to aid with focusing.

Screenshot of AstroDMx Capture for Windows Capturing DSLR images of the Moon

The images were stacked in Autostakkert, wavelet processed in Registax 6 and post-processed in The Gimp 2.10

A Stacked, processed, lunar image

Closer view

When all of the new functionality of the DSLR Live-View has been implemented it will be released as a new version of AstroDMx Capture for Linux, and will be fully implemented in the macOS and Windows versions before release.

Sunday, 5 April 2020

First light for AstroDMx Capture for Windows and a DFK 21AU04.AS camera

I reported in my last post that Nicola is working on the implementation of the DMK, DFK, DBK series of Imaging source cameras in AstroDMx Capture for Windows
The DFK implementation is now sufficiently advanced to allow for a test of a DFK 21AU04.AS camera.

A Skymax 127 Maksutov was mounted on a HEQ5 GOTO mount and a DFK 21AU04.AS camera was fitted with a 2.5 x Barlow and placed at the Cassegrain focus.

A 10,000 frame SER file of the 44.7% illuminated Venus was captured using AstroDMx Capture for Windows.

AstroDMx Capture for Windows capturing data on Venus

The best 10% of the frames in the SER file were stacked in Autostakkert!2 and post-processed in the Gimp 2.10.

44.7 % illuminated Venus



The scope was then driven to the 85% waxing, gibbous Moon and a number of 3000-frame SER files were captured of selected regions of the Moon.

AstroDMx Capture for Windows capturing data on the Crater Clavius

Crater Clavius

AstroDMx Capture for Windows capturing data on crater Schiller

Crater Schiller

Crater Gassendi

Progress is being made on a daily basis and AstroDMx Capture for Windows now has most of its planned functionality.

Saturday, 4 April 2020

First light for DMK 21AU04.AS and AstroDMx Capture for Windows

Nicola has started implementing the DMK, DFK, DBK series of astronomical cameras in AstroDMx Capture for Windows. It is from these cameras that the capture software originally derived its name when, in 2016 Nicola wrote the first AstroDMx Capture for Linux software in order that we could use our DMK and DFK cameras under Linux.
The first implementation of AstroDMx Capture for Linux had a different UI that quickly evolved into the present UI.

The original AstroDMx Capture UI showing M13 data being captured with a DMK 
back in 2016


Since those days, Nicola has implemented a number of cameras other than The Imaging Source cameras, such as QHY, ZWO, Atik, SV305, Canon and Nikon DSLRs and others. She has also implemented AstroDMx Capture for the Raspberry Pi, macOS as well as Linux, all with a unified code-base. She intends to release the macOS version, which has been functional for about a year, at about the same time that AstroDMx Capture for Windows is released. Nicola is also looking at releasing a 32-bit version for Linux.

The imaging setup for imaging with a DMK and AstroDMx Capture for Windows

A Skymax 127 Maksutov was mounted on a Celestron AVX EQ, GOTO mount. A DMK 21AU04.AS camera was placed at the Cassegrain focus and AstroDMx Capture for Windows was used to capture 2,500-frame SER files of different regions of the Moon.

The best 75% of the frames in the SER files were stacked in Autostakkert!2, wavelet processed in Registax 6 and post processed in the Gimp 2.10.

AstroDMx Capture for Windows capturing data on the Clavius region of the 
75.6% waxing Moon

The Clavius region


AstroDMx Capture for Windows capturing a 2,500-frame SER file of the 
Plato region of the Moon

The Plato region

Plato and Sinus Iridum region

Two pane mosaic of the Plato region

The Tycho region

AstroDMx Capture for Windows is stable and not too far away from completion

Thursday, 2 April 2020

The enigma of Chrome OS

Chrome OS really IS an enigma to me. At one time, I thought that I understood what Chrome OS and Chromebooks were all about. When The first Chromebooks made their debut in June 2011, they were, in the main, low powered laptops that had to be connected to the internet to work, and everything was done in the Chrome browser. Google had provided an online office suite that was good enough for many purposes and, Gmail was being used more and more as a web application rather than as an installed email client. A year earlier, Microsoft had launched its somewhat slimmed down Office Online which gave Chromebook users access to their familiar office tools, which meant that as long as they were online, Chromebook users had options for doing their work.

Although there is limited offline capability, Chrome OS was conceived as an operating system that used the browser as its primary interface to cloud-based applications and that essentially, all of the computing power resides in the cloud. This is one reason why early Chromebooks and some modern Chromebooks were quite low spec devices. I was an early taker and have (and still use) a 2012 Samsung Chromebook.


Chrome OS is based on the Linux kernel and so, in a very loose sense, you could argue that Chrome OS is a Linux distribution. My Chromebook has the GNU/Linux kernel version 3.8.11, and as the machine is past its AUE (Auto Update Expiration date), there will be no more updates of any kind. It seems however, that Google will be bringing the latest kernel to Chrome OS during 2020.

Why make an operating system so crippled that you could do just as much in any operating system simply by using the Chrome browser and just running the same cloud-based, browser applications? This seems an even more pertinent question when we consider that a number of equally low spec netbooks have been released that run Windows 10 (albeit with barely enough resources to function, particularly when it comes to updates.) These CloudBooks have, even so, much more capability as computers, hampered only by their hardware limitations.

Only Google knows the reasons behind their decisions, but between 2014 and 2016 they worked to make it possible for Android apps to run on a Chromebook, thus making Chromebooks potentially more useful computers. Of course, not all Android apps are suitable for running on a Chromebook unless it has a touchscreen, but many run fine. Android is another Google operating system with a Linux kernel, and like pure Chrome OS cannot run Linux desktop applications. Google’s solution was ARC (Android Runtime for Chrome). This would allow Android apps to be run in Chrome in any OS. This wasn’t an ideal solution for Google who went on to develop ARC++ that fully integrated the Android Runtime into Chrome OS; moreover, it allowed the use of the Play Store.

In the meantime, the Chromium team has been working on ARCVM (ARC Virtual Machine). This would make Android app support work much like the Chrome OS support for Linux Applications. At the time of writing, it is not known whether ARCVM will ever see the light of day on production Chrome OS.

Chrome OS support for Linux applications works via a virtualisation system called Crostini in which Linux is installed. Crostini is well integrated into Chrome OS and installed Linx applications are accessible and can be launched like any other Chrome OS app. Although this support for Linux applications has been available in some Chromebooks for more than a year, and is available in all new Chromebooks, it is still very much a work in progress, with support for many essentials, such as USB support, at the moment being absent.

It has been interesting to read recent articles in sources such as Chrome Unboxed that make a point of showing how Chromebooks can be made much more useful and capable by installing Linux applications such as The Gimp. This, in addition to their much-vaunted support for Android apps.

Of course, Chromebooks now span the whole range of prices found in other computers, with build qualities and prices to rival or exceed MacBooks. They also have higher specs than they used to have, with better processors and more RAM and SSD disk space; all of which make them more suited to running Linux applications that run locally rather than just cloud-based browser applications.

So, let’s sum all of this up. We have a Linux-based operating system, Chrome OS that runs apps from another Linux based OS (Android) by means of ARC++, and possibly in the future, a full virtual machine; plus it can run Linux desktop applications in a Linux virtual machine that isn’t quite finished because it lacks (at the moment) support for USB passthrough etc. All of this, running on moderate to good specification hardware, under an OS originally conceived as a system to run cloud-based applications inn a browser.

Writers talk about the virtualisation elements and the lack of USB support etc as virtues on grounds of security, as the guest system is running in a container that is isolated and thus the OS is protected. This doesn’t wash with me. It reminds me of an adage from the programming days of the 1970’s and 80’s. ‘If you have a bug; document it and make it a feature’. If Google get it right in the end, they will implement all of the missing functionality such as USB support, and then maybe astronomers will be able to run software such as AstroDMx Capture for Linux with astronomy cameras and process the data on some subsystem of their Chromebook. Chromebooks will finally become really useful devices for astronomers doing their astronomy.

At the moment, my impression of Chrome OS is that of a Shelleyan monster, with pieces bolted on here and stitched on there to make an operating system, rather than something that has evolved according to a plan that was in place at the start. Maybe it is time for Google to make Chrome OS a proper Linux distribution running on bare metal, with the ability to run Android apps but with Linux applications running natively. They have the potential to make a truly different and powerful operating system that is better than the current Chrome OS mish mash. As Mary Shelly said ‘Invention, it must be humbly admitted, does not consist in creating out of the void, but out of chaos’. Google take note, take Chrome OS and make something great out of the current chaos. Mene mene tekel upharsin!

Wednesday, 1 April 2020

Lunar imaging with AstroDMx Capture for Windows and a ZWO ASI178MC camera

A Skymax 127 Maksutov was mounted on a Celestron AVX, EQ, GOTO Mount.
A ZWO ASI178MC camera, fitted with an SVBONY UV/IR cut filter was placed at the Cassegrain focus.

The Equipment in use


AstroDMx Capture for Windows was used to capture 2000-frame SER files of 7 overlapping regions of the 43.6% waxing Moon.

Autostakkert!2 was used to stack the best 75% of the frames in the SER files and Registax 5.1 was used to wavelet process the resulting images, which were then post-processed in the Gimp 2.10.
The 7 panes were then stitched into  a mosaic in Microsoft ICE.

Click on an image to see a closer view

Screenshot of AstroDMx Capture for Windows capturing SER file data


Detail of one of the panes


Screenshot of AstroDMx Capture for Windows capturing SER file data


Detail of one of the panes


Seven panel Mosaic of the 43,6% waxing Moon

Closer view

AstroDMx Capture for Windows is stable with ZWO cameras as well as QHY cameras

Monday, 30 March 2020

Improving control of QHY cameras in AstroDMx Capture for Win/Mac/Linux

The initial testing of Nicola's re-written QHY SDK interface code to fix a QHY SDK exposure-length bug was done with AstroDMx Capture for Windows. However, the improvements are also in the Linux and macOS versions. This will be available in the maintenance release that will shortly be made for Linux.

A Skymax 127 Maksutov was mounted on a Celestron AVX, EQ, GOTO mount. A QHY5L-II-M camera fitted with a Schüler 850nm IR Pass filter was placed at the Cassegrain focus. The filter was used to image the Moon in the daytime sky.

AstroDMx Capture for Windows was used to capture three, 2,500-frame SER files of overlapping regions of the 24.1% waxing, crescent Moon



The best 2000 frames from each SER file were stacked in Autostakkert!2, wavelet processed in Registax 6 and post-processed in the Gimp 2.10. The three images were stitched in Microsoft ICE.

3 pane lunar mosaic


Nicola continues to work on AstroDMx Capture for Windows with a unified code base for all three platforms.

Saturday, 28 March 2020

Linux controlling a Windows 10 imaging laptop running AstroDMx Capture for Windows

As a continuation of our testing of AstroDMx Capture for Windows, we used Ethernet over mains to control the Windows 10 imaging computer in the observatory, using a Fedora Linux computer in the house.

As reported on October 28th 2019, we can use Ethernet over mains to remotely control a laptop in the observatory located about 20m from the house.

A motor-focuser-adapted Bresser Messier AR 102xs f/4.5 ED refractor was mounted on the HEQ5 Synscan GOTO mount in the observatory. Using a 2" adapter, a Canon EOS 4000D DSLR was placed at the prime focus of the refractor. The DSLR was USB tethered to the observatory Windows 10 imaging laptop running AstroDMx Capture for Windows.

The equipment setup

The mount was powered by mains from an extension lead and a powerline Ethernet adapter was also plugged in, and was connected by an Ethernet cable to the Windows laptop.

Ethernet over mains adapter plug

The extension lead powering the Mount via a power supply and also connecting the Ethernet over mains adapter plug.

The Windows 10 imaging computer in the observatory was running a Tight VNC server and the Fedora Linux laptop used to control the Windows imaging computer was running the Remmina VNC client.

Fedora Linux control laptop indoors

The Fedora laptop displayed the Windows 10 desktop running AstroDMx Capture for Linux, and everything on the Windows laptop could be controlled using the Fedora machine’s keyboard and mouse.

Screenshot of the Fedora desktop showing the Windows desktop in the VNC client. The Windows laptop was capturing data on M101

Screenshot of the Fedora desktop showing the Windows desktop in the VNC client. The Windows laptop was capturing data on M37

M101 and M37 were both imaged capturing both Camera RAW and Tiff images.
Eleven 3 minute exposures at ISO 6400 with matching dark-frames were captured for M101 and twenty 90s exposures with matching dark frames were captured for M37.

The images were stacked in Deep Sky Stacker and post processed in The Gimp 2.10, Fitswork and Neat image.

M101

Closer view



M37

We have used Ethernet over mains previously to control an imaging computer in the observatory with a control computer in the house. However, this is the first time that we have used a Fedora Linux computer to control a Windows 10 computer running AstroDMx Capture for Windows.

Friday, 27 March 2020

More testing of USB DSLR tethering with AstroDMx Capture for Windows.

As Nicola makes progress with the implementation of AstroDMx Capture for the Windows platform, testing of its features is vital.

A USB tethered, 14-bit Canon EOS 4000D DSLR was placed at the prime focus of a 102mm, f/4.5, ED refractor mounted on a HEQ5 Synscan GOTO Mount.

The scope and mount


The camera was controlled by AstroDMx Capture for Windows. 150s exposures were captured of Comet C/2019 Y4 (ATLAS) and a stack (made in Deep Sky Stacker) of 3 exposures was used to show the un-trailed comet.

Screenshot of AstroDMx Capture for Windows capturing data on Comet C/2019 Y4 (ATLAS)


The resulting image was post processed in the Gimp 2.10 and Neat Image

Comet C/2019 Y4 (ATLAS)


Thirty 60s exposures were captured of M81/M82 with matching dark-frames. The images were stacked in Deep Sky Stacker, and post-processed in the Gimp 2.10.

Screenshot of AstroDMx Capture for Windows capturing data on M81 and M82


M81 and M82


USB DSLR tethering enables the DSLR camera to be controlled as a regular astronomy camera, with the images being save to disk rather than to the camera SD card. It is a far more convenient and controlled way of gathering data than using a manual capturing system such as IR controller.