The Control Room is also called the warm room bc the clearest skies (the best for seeing) are in the winter, so this room is the warmest room of the facility. It's important that we keep the hatch closed since allowing the building air to flow through the dome and out of the dome shutters also negatively impacts seeing. So we don't want to open the hatch at all during our observation session. It can take up to 30 minutes for the dome to 'thermalize' again after opening the hatch.
Red lights: Even though we don't go into the dome very often during observing sessions, we still try to keep the lighting conditions the same to make it easier on our eyes to move around in low-light conditions. It could be that we have to re-point the telescope. Sometimes this requires a person to be in the dome while still taking images, so we need both environments to be low-light. And they're fun!
Data computer: The data computer is driving the three left-most screens on the desk. It's a more modern computer running windows, and supports the simultaneous data streams from multiple cameras and can even provide some small motor commands via the control computer. We do all of our image capturing (a.k.a., data capture) with the data computer. While there are some pieces of software on the data computer for imagine analysis, we generally do that on our personal computers or on one of UMBC's supercomputing environments if there are many images to analyze.
Control computer: The control computer is driving the right-most monitor. It's kinda old and runs windows along with the motor/encoder controls and the star catalog we use to direct telescope motion. The proprietary telescope driving software used by the control computer is DFM TCS. It is an API to all of the motor controls, the encoder signals that are sent back, and some celestial sphere movement. For example, we can input celestial sphere coordinates and tracking rates to the control computer. The control computer also controls the dome and maintains a sync between the telescope position and dome shutter position. The front panel is a physical interface into some aspects of the control computer. These physical switches allow us to completely de-power motors or cancel a previous action very quickly.
History: The DC was purchased right after the pandemic after the college (College of Natural and Mathematical Sciences) at UMBC. The control computer has been with us since 2014. The DFM Control Chassis is a part of the original build in 1999.
CCD vs CMOS: The old CCD was shipped with the original build of the telescope back in the early 2000s. It is capable of taking long exposures and has RGB filters inside it. A single frame takes 15s to be read off of this camera and sent to the data computer. That's SUPER SLOW –Perhaps wait 15s to demo and catch breath–
In sharp contrast, these tiny CMOS can give basically a live feed of the telescope with similar flexibility for long exposures.
Both cameras are capable of cooling themselves (slightly bigger CMOS) to reduce the impact of thermal noise on our data.
Generally, many dozens of images are taken to produce just one nice image. Some of these are the actual light from the object, the rest are calibration frames that help us understand what noise or sources of error were at play when we captures the light from the object. These are especially important for generating images of scientific quality.
Model Refractor: This tiny 2“-aperture refractor is a classic refractor. The type that Galileo or Jack Sparrow would use. Refractors suffer from chromatic aberration – where the colors of light can get spread out by the optics – impacting effective seeing or otherwise blurring your image.
Model Reflector: The larger 8” reflector is a Schmidt-Cassegrain reflector. All of our 8“ reflectors are by Celestron – a good ameteur telescope manufacturer. These telescopes can run from a few hundred to a few thousand dollars. The Cassegrain design consists of the two mirrors, primary and secondary. The primary mirror is a parabolic, concave mirror with a hole in the middle. The aligned secondary mirror (that you can't see by looking in) is a hyperbolic, convex mirror. The path of light is such that the focal plane is behind the primary mirror – where you could attach an eye piece or camera.
The Schmidt design corrects what's called a spherical aberration endemic to Cassegrain telescopes. This gives a slightly larger area of good focus and all comes from the Schmidt corrector plate, which is actually a very thin lens at the front of the telescope and suspends the secondary mirror above the primary.
Note: Our main telescope is a Ritchey-Chrétien (pronounced: richie-critchen) telescope. It uses two hyperbolic mirrors (instead of the parabolic primary) so this corrects for the spherical aberration itself – but is harder to manufacture. The main telescope therefore must suspend the secondary mirror with spokes that can generate diffraction spikes in our images.