Release of Version 2.6.3 of AstroDMx Capture

Nicola has released Version 2.6.3 of AstroDMx Capture

Mutatis mutandis

This is a feature release of AstroDMx Capture that introduces several new functions together with native support for Apple Silicon (ARM64) computers. In addition to this, there are SDK updates, various bug fixes and other improvements.

Apple Silicon

Version 2.6.3 introduces a native build for Apple Silicon computers. At the current time, this build supports cameras that have native Apple Silicon SDKs provided by the manufacturers. The list of supported cameras is as follows:

SVBONY

DSLRs

Altair

Touptek

OGMA

UVC (Web cams)

INDI Cameras

If you are Apple user and your camera is not listed above, then you should download the build for x86-64 and run it using Rosetta.

Significant New Features

A number of new features have been implemented for this release.

SVBONY: Bad Pixel Correction

SVBONY has added a bad pixel correction function into its SDK and this functionality has been implemented in this release.

After connecting to an SVBONY camera, you should notice the new functions under the “Controls: Camera” category located on the right hand side of the main UI. Depending upon the camera used, this will either just show a checkbox to active the functionality or both a checkbox and a slider. The slider can be used to alter the severity of the correction. This function is active by default.

IMPORTANT: This functionality does not exist on the SV105 or the SV205.

Plate Solver Functions

It is now possible to specify a path to the ASTAP star database. This allows for the ASTAP command line program to be in a different directory (folder) than the corresponding star databases. This function can be found in the setup UI for ASTAP.

It is now possible to automatically reduce the size of the image that is uploaded to Astrometry.net. Many high resolution astronomy cameras produce very large files which can take a long time to upload over an Internet connection. This function reduces the size of the image which allows for a faster upload to astrometry.net and faster solves. The image size is controlled by a percentage slider and can be found under the setup UI for Astrometry.net.

Disk Space Information

AstroDMx Capture now informs the user of the amount of disk space available for captures. This information is reported in the status bar (at the very bottom of the main window), in the log window and on the capture dialog box.

In addition to this, warning messages are shown in the log window if disk space is becoming critical.

Stability Features

Previously, if a camera had a glitch, it could cause AstroDMx to lockup on exit or when changing pixel formats/resolutions. If this happened, it would need the user to manually kill the application. The reason for such lockups were caused by threads becoming “stuck” in an SDK function call. Fortunately, this didn’t happen often but could be more common with specific camera types or even faulty USB cables/ports.

This version now has a monitor that detects such anomalies and, if a block is found, AstroDMx force-terminates the offending thread before handing control back to the user. This should completely remote the possibility of AstroDMx locking up due to camera SDK problems.

If such a problem is detected, the user is shown a message indicating that processing is active and asked to wait.

macOS UI

There have been changes to improve the visual appearance of the macOS user interface. This is specifically associated with the borders that group related controls. Most of the user interface has been improved but there are still some dialog boxes that are still to be done.

Version: 2.6.3 summary

Added: MacOS Apple Silicon (ARM64) native support

Added: Bad Pixel Correction for SVBONY cameras

Added: Functionality to specify the path to the star database for the ASTAP plate solver

Added: Functionality to reduce the size of images when uploaded to the Astrometry.net plat solver

Added: Disk space information for the drive where image data are saved

Added: A monitor that automatically kills the video handling threads if there is a lockup in a camera SDK. Occasionally, a camera SDK function can lockup, if this happens it would stop AstroDMx Capture from closing and would require the user to force terminate the application. This function detects such anomalies and force terminates the threads as cleanly as possible which means that AstroDMx will not lockup in such circumstances

Changes: Improvements for the macOS user interface

Changes: Improvements to the system information dialog

Updated: PlayerOne SDK

Updated: QHY SDK (all platforms, including macOS)

Updated: SVBONY SDK

Updated: OGMA Camera SDK

Updated: Atik SDK (not including ARM Linux builds)

Updated: libusb to 1.0.27 (includes changes to stop assertions being thrown in certain circumstances. These assertions could sometimes cause AstroDMx to crash)

Bug fixes and other improvements

Important Note

Initial users have reported that after downloading the Apple Silicon build of AstroDMx Capture, it reports that the app bundle is corrupt. It is not corrupt but is being incorrectly reported so by Apple. After further investigation, it appears that this is because AstroDMx is not notarised by Apple and that this is a requirement for Apple Silicon applications. 

Unfortunately, Apple Notarisation requires a significant yearly financial payment to Apple and, as AstroDMx Capture is made available free of charge, this cost cannot be justified. 

Fortunately, there is a simple solution to this problem. The procedure is as follows:

1. Double click on the downloaded AstroDMx Capture DMG file

2. Drag AstroDMx Capture.app into /Applications

3. Launch a terminal and type the following:

4. xattr -cr /Applications/AstroDMx*

5. Press enter

Once the above procedure is complete, AstroDMx Capture should run correctly.

I am pleased to say that Nicola has resumed work on INDIGO support in AstroDMx Capture

 Seestar S50 - Wi-Fi range extension

Introduction to the Seestar S50

The ZWO Seestar S50 is a smart altazimuth telescope. It is a 50mm apochromatic triplet with a built in UV/IR cut filter and a dualband 20nm H-alpha and 30nm (OIII, H-beta) light-pollution filter (atumatically or 'manual' placed in the light path. It has a built in camera which uses the Sony IMX462 CMOS sensor which has a resolution of 1920 x 1080 pixels (2 MP). The Seestar S50 has a focal length of 250mm, and a focal ratio of f/5. For solar observing/imaging, a solar filter is provided. It has a built in dew heater and the Seestar software, which runs on Android or iOS can control the scope and autofocusing. The Seestar S50 can be set to capture 10s 20s or 30s exposures or video (which can be RAW or MP4). Being an altazimuth mount, if long exposures are being used, it will depend on which part of the sky and elevation one is imaging, which exposure it will be reasonable to use. Our initial deep sky imaging was done with 10s exposures.

The scope plate solves to centre the object once located. The built in compass aids the telescope in finding it's targets. Once located and centred (which is a quick process) the scope can be set to start capturing. It captures exposures and does a live stack so you can see the image building up on the screen. (We used a 10.4 " Android tablet to get a really good view of the developing image.) 

Before the scope starts capturing images, it prepares by capturing darks which are then applied in real time to the captured images. It is possible to save just the stacked image, or, as we did, to save each of the individual exposures so that they can be stacked and processed in other software.

Equipment Required to extend the Seestar S50s Wi-Fi range

1. Two high frequency ethernet over mains adapters.

2. Wi-Fi Repeater/Access point configured as a Wireless Access Point.

3. A Seestar S50 operating in Station Mode The Seestar S50 broadcasts its own network.

Ethernet over mains Adapters

Ethernet over mains adaptors are devices that are capable of routing data via electrical power lines. In order to set up a powerline network, two ethernet over mains adapters are needed. Each device consists of a standard mains plug (containing the appropriate circuitry) with an RJ45 ethernet port.

The first device is connected directly to the local local area network in the house via ethernet and is plugged into a standard mains AC socket. The second device is plugged into the AC outlet of the long mains extension lead out by the Seestar S50, and its ethernet port carries the same data signal as the first. Once the devices are connected, they automatically negotiate the fastest stable speed.

Wireless access point

A wireless access point (AP) is a device that takes a direct ethernet connection and transmits the signal wirelessly. The device essentially creates an independent wireless network which can have its own SSID and wireless password, however, the parameters can be the same as the primary network if required.

Procedure

A power extension lead is plugged into a standard mains outlet and the other end is taken to the desired remote location close to the Seestar S50. At the remote location, a wireless access point is plugged into the extension together with an ethernet over mains adapter and the two are connected via a short ethernet cable. The local side of the network (in the house) consists of an ethernet over mains adapter connected directly to the local area network via an ethernet cable.

Everything connected to the Seestar S50 at a distance from the house

The Seestar S50 telescope is taken to an imaging location and the the wireless access point plus ethernet over mains is placed close by. A tablet computer is then connected to the Seestar S50 in the usual way, once the connection is established, the Seestar’s Station Mode is activated and is connected to the remote wireless access point.

This process projects the Seestar S50 onto the primary network which allows a tablet computer (or smartphone) to be used anywhere that is within range of the primary wireless network. In addition to extending the Wi-Fi of the Seestar S50, this has the added benefit of providing power to the Seestar S5 telescope/mount if required, by means of a Mains/USB charger via the USB C  port on the Seestar S50 so that it is not reliant on its internal battery if it is going to be in operation for a long time and maybe using its internal dew heater.

Mains-USB charger

The complete Seestar Wi-Fi extender kit

This procedure will allow the user to control the Seestar S50 from the comfort of indoors whilst the Seestar S50 is placed at a distance from the house in a place where it has optimal access to the night sky for imaging.

We tested the system with the Seestar S50 in Scenery mode. We were able to slew the scope and autofocus on objects at a distance whilst being in the house, well ouside the normal Wi-Fi range of the SeestaS50 which would have been exacerbated by the thick stone walls. The ethernet over mains brought the signal into the house network and it worked perfectly.

A tree across the valley

A wind turbine at the head of the valley

Some images captured with our Seestar S50

The Orion nebula as presented by the Seestar S50

Processed image

The Pacman nebula as presented by the Seestar S50

Processed image

The Tadpoles nebula as presented by the Seestar S50

Processed image

The Rosette nebula as Presented by the Seestar S50

Processed Image

Steve Wainwright and Nicola Mackin

Using AstroCrop to crop and register Bridge camera images taken on a static tripod.

The camera used is a Panasonic Lumix DMC-FZ72, 60x optical zoom bridge camera mounted on a sturdy Manfrotto static tripod. Images are captured at ISO 100 in burst mode (3 images per burst). If the sky stays clear during the capturing session, the aim is to capture 150 images. Allowing for the images to be saved to a fast SD card, it takes about 2.5 minutes to capture all of the images. During this time interval, there is virtually no image rotation, so stacking does not require derotation.

The first example was to image the 99.6% Moon.

At ISO 100 and 1/1000s exposure at 60 x optical zoom at f/5.9 and F=215mm. With the sensor used in the camera, this is the equivalent of 1200mm with a 35mm sensor. The 150 images are captured as the highest quality jpgs and a captured image has dimensions of 4608 x 3456 pixels

Precisely cropping and registering the images in AstroCrop.

In order to get very precise and well registered crops it is necessary to set the crop search perimeter (the distance searched away from the crop box) to a large number. We used 35 pixels . The larger the search perimeter value, the longer the cropping/registering will take. With a modern computer, the time taken is acceptable.

A single frame from the camera

The reference frame is selected and the crop box is sized and positioned

Cropping and registering in progress

Single cropped image

The cropped/registered images sum-stacked in Siril

Wavelet sharpened in waveSharp

Levels adjusted in waveSharp and saved

The image was post processed in Gimp 2.10

99.6% Moon

The second example was to image the Sun

Lumix DMC-FZ72 fitted with an ICE ND 100000 filter

A Panasonic Lumix DMCFZ72, 60x optical zoom bridge camera fitted with an ICE ND100000 solar filter and mounted on a static tripod was used to capture 69 images of the Sun at ISO 100 and 1/2000s. The images were precisely cropped/registered in Nicola Mackin's AstroCrop before being sum stacked in Siril, wavelet processed in waveSharp and post processed in the Gimp 2.10.

Reference frame set and crop-box sized and positioned

Cropping/registering in progress

Sum-stacking the cropped/registered images

Wavelet sharpening in waveSharp

The image was post processed in Gimp 2.10

The Sun showing the huge sunspot group AR3590

These two examples demonstrate that when images are captured in a sufficiently short period of time that image rotation is negligible by a camera on a static tripod, AstroCrop can crop and register the images so that a simple sum-stacking is all that is required to produce a 16 bit stacked image ready for processing. We find that capturing 150 images is sufficient to give a worthwhile image with an increase in signal to noise ratio of  12.25 compared with a single image. The camera we use is quite old and it is possible that more modern versions may capture faster and more images in burst mode. There is, however, a law of diminishing returns for the increase in Signal to Noise ratio as a function of the number of images stacked. However, the more images that are stacked, the higher the signal to noise ratio in the final image.

The 150 images does give a respectable S/N which allows for wavelet enhancing of the fine details without enhancing the noise.

Creating every synthetic narrowband image palette from One Shot Colour (OSC) RGB images

Creating every synthetic narrowband image palette from One Shot Colour (OSC) RGB images using the PixInsight Toolbox Script CreateHubblePaletteFromOSC. 

We have previously discussed the use of this script with respect to creating a synthetic Hubble Palette SHO image. I use the term ‘synthetic narrowband image palette’ because, coming from an OSC RGB image, all of the necessary Ha, SII and OIII data are simply not available as separate (or separatable) colour channels as they are in true narrowband or (Ha, OIII) and (SII, OIII) pairs of dualband images.

The CreateHubblePaletteFromOSC script takes an OSC RGB image and produces reasonable approximations of all of the narrowband palettes with the exception of SOH (which I feel must be an oversight). It also produces an approximation to the HOO two element palette.

Fortunately there is a Utility script called Swap channels that allows us to take an ‘OSH’ image produced by CreateHubblePaletteFromOSC and swap the R and G channels to produce an ‘SOH’ image.

Whilst many astro-imagers regard PixInsight or Siril etc to be ‘one stop shops’ for all of their image processing, my approach is to use whatever software I feel is most appropriate to my workflow, which includes a number of programs such as the Gimp, Neat Image and Photoshop CS2.

As previously, we start with an OSC image of the Elephant trunk nebula captured using AstroDMx Capture, through an Altair Starwave 60 ED refractor with an 0.8 reducer/flattener and 2" magnetic filter holder with an Altair 2" Quadband filter, and an SVBONY SV605CC OSC 14 bit CMOS camera. 

It is best to work with starless images for processing nebulae and this was done with StarXterminator in PixInsight.

Invoking the StarXterminator Procedure

Starless image an a stars image produced

Launching the CreateHubblePaletteFromOSC script

Producing a 'HOS' image for example

Synthetic narrowband images produced by the CreateHubblePaletteFromOSC script

All of the starless, synthetic narrowband palette images were saved along with the stars image.

Using the Swap channels script on the 'OSH' image produces an 'SOH' image which was saved

The starless images were stretched by the same amount, below are three example

The images were denoised using the same settings in Neat Image as the three images below illustrate

Table showing the synthetic palettes in the montage of images below with the OSC RGB original at the bottom right

Montage of synthetic palettes as shown in the table above

The CreateHubblePaletteFromOSC Toolbox PixInsight script produces sufficiently good analogues to narrowband palettes that allow an imager using an OSC camera producing RGB images to be able to present their data in a way other than simple RGB.