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How ACP Works

ACP and other programs work together. Each program is useful in its own right, but when operated together by ACP, they form a system for acquiring images that blows away the competition. ACP provides the automation hub for the observatory. It sequences the observations and controls the telescope, CCD imager, filter wheel, auto-guider, focuser, and dome.

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Most GOTO mounts have imperfect pointing. ACP's unique Every Image Centered™ provides both self-learning model-based pointing correction and a "digital finder scope" function to solve this problem. While the pointing corrector learns about your mount's error, ACP ensures that every image places your target in the exact center.

From the first image you take, everything is centered! It learns by matching image stars against a catalog. This provides "closed-loop" control, ensuring that the telescope is always precisely on target no matter what. As it learns about your telescope's mechanical behavior, it forms a model which is used to correct pointing. Eventually, ACP learns enough to virtually eliminate last-minute centering adjustments. All of this is done automatically. No need to separately gather mapping points, run an analysis program, etc. You just go to work and ACP gets better as time goes on.

MaxIm DL/CCD provides scriptable controls for the camera, filter wheel, and the auto guider. ACP's scripts use these controls.

FocusMax ties into the focuser, telescope, and CCD imager via ASCOM, sharing devices as needed. It offers an AutoFocus function that ACP uses to do automated autofocus. ACP monitors the Half Flux Diameter of every image it takes, and can optionally refocus if the image quality degrades. Or you can tell ACP to refocus periodically and/or after filter changes. You can also set up a table of filter focus offsets, eliminating between-filter auto-focus runs.

For advanced users, nothing else has the flexibility and power of this system. The huge advantage is that you can fully customize the entire system. You can edit the web pages. You can edit the control scripts. You can add image processing features, integrate in other hardware (e.g. dome, weather station), or whatever else you can think of.

With this combination, you get automatic image calibration, pointing corrections (or TPOINT usage), and auto-guiding without any intervention on your part. A detailed log is produced, allowing you to diagnose problems and tune your system for best operation. Images can be automatically flat and dark corrected, plus astrometric info in the form of WCS coordinates are added to the FITS headers. In short, this is a professional-class automation facility!