The DRAGONFLY Telescope

[JA]

Hello Folks,

Here is an interesting account of a telescope (Or as they've called it, telephoto array) made of an array of 48 Canon 400mm 2.8 II L Lenses. They didn't state the equivalent aperture of those 48 lenses, so working it out - every doubling of area of the light gathering (doubling of lenses) is equivalent to 1 f-stop lower aperture- i.e: (2^(0.5)) = 1.414x... lower aperture .... So that works out to .... ???

1 lens - 400mm f/2.8
2 lens array 400mm f/2
4 lens array 400mm f/1.4
8 lens array 400mm f/1
16 lens array 400mm f/0.7
32 lens array 400mm f/0.5
64 lens array 400mm f/0.36

So for 48 lenses it's around (too lazy to be exact) 400mm f/0.4 - No too bad. Start saving your favourite telephoto lenses!!! These were $10k each.

Best
JA



See story here ... >>>
https://www.dpreview.com/news/6196210055/this-array-of-canon-400mm-lenses-helped-astronomers-discover-new-galaxies

[Merlin66]

Whooooo!
There's a fair amount of $$$$$ tied up there.
The effective Aperture will increase, but as each lens is independent the f ratio will still be f2.8.
Stacking the 48 (?!) images gives the performance....

[omegacrux]

Seen this on fb pretty crazy in an awesome way

David

[Slawomir]

This kind of system got me thinking of having 3 telescopes for simultaneous collection of Ha, OIII and SII data...maybe it is now slightly less impossible with recently released more affordable CMOS cameras...or even better, it would be very nice to have a 3-layered sensor with each layer collecting only one particular wavelength and at the same time being transparent to the rest of the incoming light...or reflecting the rest of incoming light to another sensor within the same camera...okay, where is my toolbox?

[JA]

And here is a lecture on the need for such an instrument and use ...https://youtu.be/EUr1mxanYmc

Best
JA

Hopefully that embeds it as a youtube ????

[Lognic04]

Suavi, maybe something like a dslr Bayer filter, because the individual pixels are optical filters for RGB, or probably better something like a Sony mirrorless transparent mirror(see pic) that reflects the light to a viewfinder, replace the viewfinder with a sensor and you're set:thumbsup:
:question::question::question:http://www.cs.mtu.edu/~shene/FORUM/Taiwan-Forum/Newbie/15-Mirror-Pentaprism/Sony-SLT-Cutaway.jpg