Astrel Flatbox Controller - for AST8300 cameras

Astrel Instruments Controller for even flats

One feature of all cameras with the KAF8300 is the internal shutter. This feature makes generating uniform flats difficult, as it needs a bit of time to open and also to close. Only at exposure times of at least 5 seconds, the gradient becomes acceptable. However, this eposure time is too long for most flatfield boxes.

The controller box allso allows for ultra-short exposure times, thus you can use almost any flatboxes, even brighter ones without control. The trick is simple:

1. The internal shutter of the camera opens. The flatbox is still dark.

2. The flatbox is switched on and off by the controller box for only a short time - exactly as long as you need for a good flat frame.

3. After the flatbox is switched off, the internal shutter is closed again.

Thus you can generate perfectly illuminated flats with less than one second exposure time. There is one prerequisite, the flatbox supply must be 12 V.