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Hi Bojan,
What they claim is that the almost total lack of reflections and scattering that you would otherwise get on every other optical surface of a reflector or ordinary refractor telescope in existence gives rise to a theoretical limit on the resolving capability of 28 magnitudes.
That is the SNR gain they are taking advantage of.
Their optics dont have this problem so they can go down to 32 magnitudes.
That is to say that the optical noise produced by the minute amount of reflection and scattering at the wavelength level of imperfection on ordinary glass surfaces is enough to limit their ability at 28 magnitudes
Theirs doesnt have this thanks to Canons process.
Thats their SNR magic bullet !
The result of Canon's "nano fabrication coating" is that the surface of the optical elements is to all intents and purposes perfectly "smooth" because it is well below the length/height of any of the wavelengths of light they are interested in and thus in effect invisible to the optical system.
As a result of this they have reduced the inherent optical noise so that they can resolve down to 32 magnitudes.
All the rest of the stacking just helps with ordinary sensor and data collection noise reduction and improved integration time - more light for in same time. Its nothing special at all - but just as necessary as normal to imporve SNR, remove sensor and processing noise etc etc
As soon as others are capable of coating their surfaces in the same manner, I guess their technical advantage disappears and Im sure that might happen, but there may well be some manufcaturing and technical limitations (and patents) that make this difficult or impossible for larger elements such as big refractors and mirrors.
In answer to your question "what is the difference (apart from saving time) between stacking subframes taken by array of telescopes and stacking frames taken sequentially by a single telescope? "
There is no difference whatsoever ! - you seem to miss the point - the gain they claim in their papers (and their published results appear to support it) is their ability to avoid the increased noise of surface imperfections that exist on other optics.
I do not believe they are using 1980's technology, my understanding is that its latest technology, some published articles list the actual model number of the lens, current retail pricing is about $10kUS and that corresponds with their costed model.
Hope that makes sense.
For an amateur maybe $2k or $10k for a lens is a lot but for a research project that is finding and discovering what they are uncovering - its not really a big investment, just a matter of them getting appropriate funding to go further and based on their findings - I would be surprised if they didnt get funding for their 480 lens system.
They did all this on a baby Paramount with photographic lenses not a Magellan or a Hubble !
I just started at their website and a few press releases and then started reading the links that progressively went further into the actual research papers. Its all discussed openly and details presented.
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