Si Pin Detectors

Focusing a Telescope

The movie on the right shows images of a star captured on an H4RG Silicon Pin Detector at the Kitt Peak 2.1 meter telescope in Arizona while the telescope is being focused.

It starts with the telescope out of focus, which is why the star appears so blurry in the beginning frames. As the movie continues the telescope gets closer to a proper focus, so the star gets smaller, but the shimmering continues due to atmospheric turbulence.

While the movie is not real time (it runs at about 3 times the real speed at which the pictures were captured), it still shows the novel high-speed capability of the H4RG detector; an 11" x 11" field captured at 10 frames a second. The dark pixels that do not show light are artificats of the detector that can be removed with proper image processing techniques. (Double - click on picture if movie doesn't play)