PerfectStar Goes Bipolar

In this case “bipolar” does not refer to a disorder, but to a type of motor.  The current version of PerfectStar, like most focus controllers, uses “unipolar” stepper motors.  The indirect reason for this is that I (and probably most of my competitors) designed the controller to be compatible with existing motors (and for the motor to be compatible with other controllers) despite some significant advantages of bipolar motors over unipolar.  I’ll provide more details on that later, but first, I want to point out some other changes. In the above photo we see the “front” end of the controller. […]

PerfectTemp Temperature Sensor

Temperature compensation is a great feature of the PerfectStar focus controllers (excluding PerfectStarLite), but to perform to its full potential the sensor must read the temperature of the telescope accurately and not be influenced by the surrounding air, since they will change at very different rates.  That is, the sensor must be thermally coupled to the telescope tube and insulated from the air. This can be done with the standard sensor, but requires some planning an effort on the part of the user.  PerfectTemp makes it much easier:  Just place the sensor block face down on the telescope tube, secure […]