Chris Peterson wrote:alter-ego wrote:The telescope is designed for light collection, and not for imaging in the classical telescope sense. Each element just needs to send photons to a multi-element detector for signal amplitude, and, I'm speculating, maybe providing some limited spatial imaging capability(?) along with having different performance characteristics (e.g spectral information).
I believe these are true imaging telescopes, not simple energy collectors. The cameras have 3.6° fields of view, and 576 pixels, which have individual imaging scales of 0.1 to 0.2 degrees, depending on their location in the sensor array.
That's true. My statement overconstrained the definition of an imaging optic, and I should have elaborated a bit. To qualify as a "classical" imager, I imposed the criteria that all the mirror elements have to be cophased, i.e. at least near-diffraction limited which MAGIC telescopes are far from that. Geometrical imaging using element sub-telescopes with overlapping, non-interferring, intensity spots is a valid form of "imaging". Said another way, a poor-quality (relatively speaking!
) optical telescope will still be an imaging telescope, just not a good one.
FYI, the minimum focused spot size achievable by the MAGIC telescopes ≈ 5mm @ 17m, or about 20% of the camera's central, higher resolution, PMT 1" aperture. The picture shows element mirror point-source images before alignment and at "best focus" (inset)
