Flarestar Observatory - Concept & DesignFlarestar Observatory is a compact yet versatile structure, designed to house astronomical equipment while accommodating future telescope upgrades. Its discreet design blends seamlessly with its surroundings whilst operating quietly to ensure minimal disturbance to nearby residents.
The run-off roof observatory was acquired through Tecnosky in Italy and is manufactured in Spain. It extend a footprint of 2x2 meters and features insulated panels on all walls and the roof. These panels effectively prevent thermal buildup during the day, particularly in the intense heat of summer, ensuring a cooler and more stable interior environment. Mounted on a solid steel platform, the unified structure combines a thick aluminum exterior with 3.5 cm thick insulation on both the exterior and interior sides. Both the wall and roof panels are maintenance-free and engineered to endure harsh environmental conditions. The roof slides open smoothly along side rails into three panels and is guided by two heavy-duty nylon belts on each side. This set up provides unobstructed all-sky access without the need to align the structure with the telescope. Its quiet operation preserves the tranquility of the observatory's surroundings. For aesthetic purposes and in view that the observatory is unattended most of the time, the observatory walls were custom-built to obtain a reduced height that does not compromise equipment functionality or observational efficiency. Designed for full remote control, the observatory is operated autonomously, requiring no human presence on-site. Prior to its stand alone operation, its systems were pre-configured and rigorously tested to ensure reliable and seamless robotic management. The ready-made approach guaranteed optimal performance from the outset, minimizing setup time and ongoing maintenance. The Flarestar Observatory exemplifies a commitment to its photometric research program through reliable automation. Its durable, low-maintenance design and efficient remote operation enabled the acquisition of uninterrupted astronomical observations night after night whenever the sky is clear enough to allow for the gathering of accurate photometric data. Telescope, Cameras & SoftwareThe primary optical instrument is a Meade Instruments SSC-10 Schmidt–Cassegrain Telescope (SCT) operating at its native f/6.3 (effective focal length ≈1600 mm). The selection of a 10-inch (254 mm) aperture SCT reflects an optimization between light-gathering power, system compactness, and mechanical load constraints.
The Schmidt–Cassegrain Design was the preferred choice as it provides:
The telescope is mounted on a EQ8 Pro equatorial mount. The selection criteria were:
Mount control is achieved through ASCOM protocol via direct EQDIR interface, eliminating dependence on a manual hand controller and enabling deterministic software-driven control loops. The remote pointing and slewing of the telescope, fundamental to its functionality, are executed through the utilization of Sequence Generator Pro (SGP) software. This software serves as a sophisticated and capable tool for the precise control of the telescope, enabling the control of all the observatory's instrumentation. Imaging CameraThe main scientific camera at Flarestar is a QHY268M monochrome CMOS camera that employs the Sony IMX571 back-illuminated (BSI) sensor. This camera was selected after evaluating several other imaging systems for scientific work. In the end, the QHY268M was chosen as its workmanship is of high quality and the native 16-bit A/D electronics inside produce extremely low read noise levels (0.7–1.1 e−) that are desirable for achieving high-quality data. Although the Sony IMX571 has a high resolution of 26 Megapixels (6280×4210), the 3.76 μm pixel size is an ideal match for various focal lengths and local atmospheric seeing. The APS-C dimensions of the chip at 23.5 × 15.7 mm (28.3 mm diagonal) is large enough to cover a good range of comparison stars for high-precision aperture photometry. Furthermore, the sensor's sensitivity is quite high with a peak quantum efficiency of 80%–91%, and the variable Full Well Depth of 51,000 e− to 80,000 e− is a great photometric asset for bright targets and exoplanet transits. Camera cooling for the QHY268M utilizes a dual-stage TEC capable of reaching −35∘C below ambient.
The QHY268M camera employs a IMX571 back-illuminated (BSI) sensor that has a Quantum Efficiency of 91%, peaking at around 450 nm.
At Flarestar, flat fields are taken by illuminating a translucent panel that is illuminated by reflected light hitting the back wall of the observatory. The even reflection enhance the quality of the flat fields as the light from the strategically placed wide-spectrum light is evenly distributed. The light source used emits a good portion of its light in the infra-red that is desirable when working through at this bandpass. Sky-flats can also be taken when desired. An colour-enhanced flat field is depicted below that shows the a maximum range of less than 3% across the image.
The QHY268M camera at Flarestar is equipped with a QHYCFW3 electronic filter wheel that accommodates five filters. This filter wheel is specifically designed to house five 2-inch mounted or 50mm unmounted filters, making it an ideal match for the APS-C sensor of the QHY268M. The QHYCFW3 filter wheel model features a high-speed direct-drive motor that reverses direction to take the shortest path possible when switching positions, effectively saving time during complex remote imaging sequences. For streamlined cable management, the wheel is powered and controlled entirely through the camera’s 4-pin socket, though it can also supports a standalone USB control mode with a dedicated, threaded 12V DC power port to prevent accidental disconnections
Flat field Acquisition
Digitally enhanced false colour image of a flat field acquired through the method described above. Variation across the field is less than 2% of the well depth capacity of the sensor. The gradient shown here has been exaggerated to show gradient effects.
Photometric FiltersFor photometric measurements, B, V, R, I (Bessel/Cousins) filters have been fitted onto the camera's internal filter wheel to convert instrumental magnitudes into the photometric B,V, R,I standard . A Clear glass (C) filter is also employed to maintain the same focus when switching from coloured filters to white light.
Although photometric work predominantly occupies the observational schedule, occasionally, aesthetic colour images have also been taken. Aesthetic images are acquired through a Canon DSLR camera that has been used to take pictures of celestial objects ranging from comets to distant galaxies. The quantum efficiency of the DSLR is quite low when compared to modern CMOS cameras, however, the sensitivity of the DSLR is still good enough considering it is a one-shot colour camera that enjoys a generous wide field of view. 
B, V, R and Cousins Infrared (Ic) photometric filters are installed onto the camera's filter wheel to convert instrumental magnitudes into the standard BVRI system.
Software for System OperationSequence Generator Pro (SGP) is the software of choice to operate all equipment remotely. SGP PRO operates the main camera, the telescope's mount, the autoguider camera, the autofocuser motor, and the observatory’s roof. SGP interacts with the autoguider via the PHD2 software avoiding the need to flip between program windows when in operation. SGP also operates the auto focuser routine as well as the programmable operation of the mount via a GUI interface. This program has also been used to operate the DSLR remotely when needed. The observatory’s roof is operated by SGP through software driver that acts as an interface between the 12-channel Denkovi remote switch module and the roof motor.
The pointing of the mount to center targets is done through SGP's plate solving subroutine software that is achieved within seconds. Via plate solving, the software can achieve pointing precision down to well less 1 arc minute easily. This ensures that no matter how small the field of view is, the target is always centered on the main sensor of the camera. The goal of SGP is to provide a best-in-class image capture suite for astrophotography and scientific imaging. SGP's philosophy is based on the concept that a lot of equipment is rigged to the telescope and sometimes it is difficult to get it all working together. SGP PRO was written in a way that is capable of executing complex sequences of capture events through a straightforward process without the need to go into any scripting processes. Thus, this great program allows spending more time acquiring images and less time dealing with rigging issues. 
Sequence Generator Pro controls the all the operations at the observatory. Plate solving, interaction with the PHD2 guiding software, camera control and the setting of image sequencing permits the system to function with minimal user intervention. The only interaction required at Flarestar concerns the opening of the observatory and initial flat-field calibration. SGP then takes over all the necessary functions required for the night.
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The Observatory's Structure
Flarestar Observatory is implemented as a compact roll-off roof facility specifically engineered for precision time-series photometry. The 2 × 2 m enclosure is constructed from insulated aluminum composite panels mounted on a rigid steel platform. This configuration was selected for three primary scientific reasons:
Utility EnclosureThe utility support storage serves as a hub for the observatory's essential components, including power supplies, electronic modules, and other accessories. The cabinet lid can be opened to access a supplementary PC. The main control PC, a mini-PC, manages all operations during autonomous functioning.
The choice of a mini-PC offers significant advantages, as its proximity to the telescope equipment minimizes interruptions caused by cable length. To prevent heat buildup, air vents are installed within the storage unit. A 1500 VA UPS unit provides backup power, ensuring safe system shutdown in the event of a power failure. The UPS is remotely manageable through the observatory's PC browser and functions as the observatory's central control hub, coordinating operational commands for the telescope and other connected equipment. 
UPS management as accessed through the web browser. Any anomalous values help to readily identify any possible equipment failure.
Remote OperationGiven the long hours often required for time-series photometry, remote operation was deemed essential from the outset. Observations are managed using SGP Pro software, monitored from a home-based "control room" located approximately 15 meters from the observatory. However, the distance to the control room is inconsequential, as the system is accessible remotely from anywhere via the internet, including smartphones.
The observatory's PC, which controls all equipment, is connected to the internet through an external CAT-6 LAN cable. An 8-port 10/100 Mbps Ethernet network switch facilitates simultaneous connections for the PC and cameras, allowing real-time monitoring of telescope operations. The equipment also interfaces with the PC through an 8-port relay module, enabling remote power control of all observatory equipment. The observatory's software and ASCOM drivers act as a safety net, automatically initiating a shutdown procedure whenever conditions—whether atmospheric or technical, such as a power outage—fail to meet operational requirements. Monitoring and controlling the observatory's PC is typically conducted using Google's Chrome Remote Desktop, which operates through a web browser. This software allows seamless access and management of the observatory system via another computer or a smartphone over the internet. Having control to the observatory's PC enables the operation of the telescope, cameras, autoguider and observatory roof to act as a coherent unit. However, despite all of the precautions taken to ensure optimal operation, this was not considered as being enough to ensure that all goes well. Cables might get snagged and clouds might roll in. To overcome this problem, two IP cameras with IR capability have been employed. One camera oversee the status of the telescope's mount while the other acts as a supplementary cloud monitor. The cloud camera employs a high definition (HD) sensor that is sensitive enough to detect high thin clouds as well as stars down to 5th magnitude. When the observatory is closed, these cameras also act as security camera along with other security measures.
An internal camera is employed to ensure that the telescope is operating as it should be. This cam is also useful to ensure that the telescope is parked prior to roof closure.
Image capture from the All-Sky Camera acts as a back-up cloud monitor to the AAG. Although PHD2 alerts when the guidestar is lost due to clouds, this camera is very useful to determine whether it was due to a passing cloud or not.
Having a lot of equipment at stake at the mercy of unpredictable weather conditions is set to bring about sleepless nights. As an additional precaution, a Lunatico AAG CloudWatcher unit has been installed. This system triggers an alarm at home in case the sky clouds over or the tiniest of rain droplets falls unexpectedly. Alarms are set to trigger a function within SGP that parks the telescope to close off all equipment.
Weather details through the AAG are embedded on the FITS headers of each image generated by the main camera. The AAG utilize an internal infrared sensor and thermometer that enables it to measure the temperature of the sky and derive cloud intensity above the observatory. The AAG also incorporates a light sensor to distinguish between day and night. Approaching daylight triggers a function to park the telescope when the sky gets too bright for observation. An embedded temperature sensor is used to read the ambient temperature at the observatory and can be used to trigger autofocus routines at the telescope to maintain focus throughout the night. Relative humidity and atmospheric pressure are also monitored by this device that can be useful to detect an approaching weather front that may bring about adverse weather conditions. 
In case that the observatory PC hangs or some other action at the telescope is not carried out in a specific time, an independent software by Lunatico Astronomia called GNS or 'Good Night System' is used on a smartphone to monitor the timing of all operations. Whenever an event operates outside the limits programmed, an alarm is triggered that alerts the observer to take over command. Autofocus
The ZWO EAF (Electronic Automatic Focuser) motor, integrated with SGP Pro software, automates the focusing process, ensuring precise and reliable adjustments during observation sessions. Operating at 5V with a step resolution of 0.04mm, it seamlessly maintains optimal focus, even as temperature changes impact the telescope's focal length. Its quiet operation, compact design, and USB connectivity make it ideal for Flarestar Observatory's remote setup.
Autoguiding
Autoguiding is achieved through the use of an Orion ST-80 Guidescope that is mounted on the telescope's OTA. This small 80 mm aperture (400 mm focal length) telescope is a very good instrument for guiding, as its aperture is big enough to enable guiding on stars as faint as magnitude 11.5mv using 2.5 seconds exposure. The camera employed for autoguiding is a ZWO ASI120MM that utilise a monochrome CMOS chip (1280 x 960 pixels of 3.75 µm square). Through this set-up this system ensures that a guide star is always available for autoguiding wherever the telescope is pointing to.
The software of choice for autoguiding is the popular PHD2 Guiding that is also controlled by the SGP software. PHD2 is the enhanced, second generation version of the popular PHD guiding software from Stark Labs.
In PHD Guiding, all calibration is taken care of automatically. There is no need to tell it anything about the orientation of the camera. The automatic calibration routine takes care of this. Once correctly configured through SGP PRO, the software can also automatically choose a suitable guidestar and starts autoguiding without any further user intervention. 
Analysis Software
Data reduction and light curve extraction are performed using MPO Software Canopus, optimized for asteroid and variable star photometry. Standard reduction steps include:
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