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.
![Image](http://wwwmagic.mppmu.mpg.de/gallery/pictures/Mirrors/focusing.jpg)
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!
![Smile :)](./images/smilies/icon_smile.gif)
) 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)