World wide dragonfly.

[xelasnave]

I expect all know about the dragonfly project.
I am particularly fond of the idea because I had it a long time ago and someone did it proving my idea was not entirely ratbag.

Well I was thinking today what with stacking and all why could we not form a group of folk around the world all using the same gear and stack a couple of thousand multi hour contributions into one image.
Now I know it will work but no doubt members here will be able to ppint out why it wont so in anticipation I call for a committee to be formed to solve all problems ptesented:)

Could we do it.
Say a group with 100 mm espirts and zwo 1600 cams...or the like.

Alex

[xelasnave]

If you look at the big scopes they are now made up of many segments...one with near 800 individual mirrors...

Would separation by half a world give any advantage?
Alex

[Atmos]

Stacking multiple images together would work as long as they’re of a minimum standard otherwise the poor quality ones will muddy the pool ;)

As for long base line imaging, this is routinely done in radio astronomy but sadly it doesn’t work in optical. The large professional telescopes with hundreds of segments work because they’re all pointing towards the same secondary mirror and hitting the same CCD. So for optical astronomy it doesn’t matter if the telescopes are across the globe or across the street.

[JA]

Continuous collection of data would be one advantage- it's always night somewhere.

Best
JA

[Wavytone]

Conceptually it would be possible to image the entire night sky, every night, using an army of robotic internetted smallish scopes. I'd make them solar powered, with a panel to charge and a battery for storage, and a wireless data connection to whatever carrier is available. Programmed to take a bunch of images suitable for stacking around local midnight and dump the images onto a server in the cloud.

Assemble enough of these scopes to provide full coverage of the sphere formed by the night sky, allowing for some overlap. This is a compromise in therms of focal length and sensor size vs the number of scopes, but definitely within the realm of doable. If each camera covers 4 square degrees it would require tad over 10,000 scopes. Programming each scope to take images of say ten portions of the sky instead of 1 per night reduces the number of scopes required by a factor of 10, say 1,000. For each chunk of sky to be imaged, lets say 10 shots at 30 seconds apiece, so each camera would take 100 shots each night, for an imaging run lasting about an hour.

Now the locations. Assuming we could install them at any point on the globe, have every scope imaging at their local zenith. That way the entire dark side sky would be covered once, every night.

However there is an issue with inaccessible or insecure locations (oceans, the poles, Himalayas and deserts etc) and locations that are hopelessly cloudy. For the cameras that would have been located in these, merely relocate them to a more suitable location where there is internet access - but still have them aimed at their designated patch of sky by hour angle and declination.

Once deployed, at the server side, stack the images from each camera for each night. The result is an image of the entire night sky, every night. With 1000 cameras producing 100 frames per night, that's 100,000 images per night requiring a potentially a few terabytes of storage per day. A petabyte per year. And the backend has to munch through this lot faster and dump the old frames than the images come in - or it will be inundated.

Now... as for what to do with that data... deploy a web application in the cloud (utilise the massive computing power in the cloud) which takes each group of 10 frames, stacks them to produce the final image for each chunk of sky and compares the images night to night for changes, eg supernovae, asteroids on collision courses with Earth, alien spacecraft... whatever.

Sounds like a plan - anyone with a server farm lying idle, and friends in high places in Google, or AWS ?

[lazjen]

Nice one Nick. :)

I seem to recall someone on Astrobin doing like this - because my data was included in one of the images. Used many sources to create an image. Wish I could remember the details now.

[Atmos]

https://www.astrobin.com/119854/?nc=user

[RickS]

As well as the pic that Colin posted there is a thread by Morten on the PI forum about his Crowd Sourced images:

https://pixinsight.com/forum/index.php?topic=7506.0

[xelasnave]

Thanks to all for your contributions here.

Well I am happy that the idea was reasonable and better still it is being done.
Alex

[multiweb]

I like that idea.

[CalvinKlein]

I'm fascinated by this concept Alex. I love the idea of the Dragonfly arrays. Combining data from multiple sources makes a lot of sense !

I'm slowly working on my own triple-imaging system using a 127mm triplet refractor & 0.7x reducer with Canon 6D and a couple of F2.8 EOS lenses with cooled ASI cameras. All three have similar field of view. I regularly use the two ASI cameras & DSLR lenses together - one for mono (luminance and Ha) and the other for the Colour. Works well.

[xelasnave]

Wonderful set up there Kelvin.
Thank you for posting.
Alex

[RickS]

Hi Kelvin,

I'm trying to do something similar with Nikon lenses and ASI1600mm and ASI294MC cameras. At present I'm tweaking the spacing trying to improve the stars in the corners. The recent weather in Brisbane hasn't helped...

Cheers,
Rick.

[CalvinKlein]

I'd be keen to see your setup Rick. It's still early stages for me with all this but AstroPixelProcessor has made combining the different images a breeze.

Here's the setup with my Samyang 135mm / ASI1600 and Tamron 70-200 F2.8 @85mm / ASI183. (both similar FoV).

From what I've read dark skies are a necessity for the ASI183MC-Pro. The ASI1600MM-Pro on the other hand is happy imaging anywhere and under any conditions :-)

My goal for all of this is to get as much imaging information for multiple targets in the shortest possible time on the rare occasions I can get out to a true dark site.

This bad run of weather has pretty well killed my chances of getting the North America / Pelican nebula for the year - I might get one more crack next month if I can find a high location with zero light pollution to the north.

[RickS]

Hi Kelvin,

I don't have a side-by-side set up yet. I'm just testing the individual components one at a time on a Star Adventurer. I have an Astro-Physics AP900 that I'll use for the dual system.

Cameras are an ASI1600mm and ASI294mc which I'll be using with camera lenses (lots of them... Samyang 135mm f/2, Nikon 85mm f/1.4, Nikon 50mm f/1.2, Zeiss 21mm, 35mm and 100mm, etc.) and a Borg 55FL f/3.6 scope that should ship from the US shortly. At present I'm just trying to sort out spacing and tilt so that I can get decent looking stars in the corners.

I hope to do a lot of narrowband from home with the ASI1600mm and then, like you suggest, suck down photons as quickly as possible with both systems on the rare occasion that I get out to a dark site.

Cheers,
Rick.

[CalvinKlein]

Very nice setup with your SA Rick. I pushed mine well beyond its recommended limits before buying my EQ6-R and am keen to get back to using it again alongside my heavy mount. I was regularly able to get 5min exposures at 500mm.

I've had intermittent issues with tilt I suspect due to the ZWO EOS adapters - even with mounting the lenses to take the weight off the adapter. I couldnt justify the cost of a Geoptik locking device so I got a similar device off an Aussie eBay site that I expect will arrive today. I dont think it will be able to replace the thinner EOS-T2 EFW though as its a couple of mm too thick. Its the normal ZWO EOS-T2 I've had most trouble with anyway.

That Borg looks like an amazing weapon !!

I looked at most of the short, fast OTAs around the 350mm FL mark - most had some quirk that users were unhappy with. Others were just plain difficult to order into the country. I ended up buying a second hand Sigma 120-300mm F2.8 sports lens for similar money. It rates extremely well for sharpness out to the corners even wide open, at almost all focal lengths. I was taking a big punt as I couldnt find anyone else using one for Astro. So far I'm very impressed - and of course it makes a good wildlife / sports zoom lens during the day :-)

[RickS]

That's a heavily loaded SA, Kelvin, and the Sigma lens looks suitably impressive.

I have one of the Geoptik adapters for Nikon but, unfortunately, it was about 1mm too thick to work with the ASI1600mm and EFW. Starizona have an adapter that looks to be good quality but it is expensive and also doesn't have enough back focus for the mono camera and filter wheel. Let me know what you think of the Geoptik look alike when it arrives.

Cheers,
Rick.

[lazjen]

Rick, if your filter wheel was the ZWO one, you might be able to switch to a Xagyl FW instead - from memory it's 1 or 2 mm thinner than the ZWO version.

[RickS]

Hi Chris,

Yes, the specs say the Xagyl filter wheels take 1mm less when used with their adapters. I have a workable solution with the ZWO EFW/Nikon adapter and some thin spacers but worth keeping in mind as a future option.

Cheers,
Rick.

[CalvinKlein]

Hi Rick

Well I can report that the eBay Geoptik work-alike is excellent.
I managed to find a 7.5mm T2 extender (Baader - courtesy of Astro Anarchy).

So I now theoretically have a strong & squarely coupled and perfectly spaced solution to the Samyang 135mm-ZWO camera tilt, mounting and spacing problems.

It seems to be such an elegant solution to everything else I (and others) have tried.

So we have 19mm for the EOS-T2 adapter, 7.5mm for the Baader extender, 11mm for the ZWO extension ring, and 6.5mm to the sensor = 44mm total. I sure hope I have my maths and flange-focal-distance theory correct !

Hopefully tonight or tomorrow morning after 5 weeks of cloud I will get to try it out.

cheers Kelvin

[xelasnave]

It seems that if we wanted to we could with the software available combine all our images ... so it would not be to difficult to set up a place we could download our images and process the lot...say of one of the clouds...I dont know what could be done with such a set up..maybe help science ... mmm we need a committee☺
Alex

[xelasnave]

You probably could set up a site like there are hosting photos with as a kicker to use our site to engage in a monster photo project ...
Alex

[xelasnave]

If you could write a program for S/N such that you could statistically anaylse each photo against the average of the group and refine what you could treat as signal.
Its not raining but I cant get out of the rainy day mentality.
I should set up its clear but the Moon and it will be so wet ...I have tried in these conditions and its tuff...plis I cant drag the genny over the muddy lawn to set up...
I bundled the mount power cord with all the camera and guide cables..bad idea...I could just go unguided with the dslr camera and 200 mm lens just for the heck of it...
Alex

[RickS]

Thanks for the update, Kelvin! I might have to get one of those adapters to add to my collection. I also have one on the way from Astro Hutech.

Are you using a UV/IR blocking filter with the ASI183? I tried using the ASI294 without one and the results were truly awful.

Cheers,
Rick.

[RickS]

Hi Alex,



On Astrobin you can use a Creative Commons license to make your images available for use in projects like this.

[silv]

Alex, that's a cool idea! and +1 from me for the committee!
I googled "dragon fly project" and it came up with a) a virtual bereavement/sympathy card sending site and Google's censorship interests [in China]. Can't imagine a reason why your brain circuits would associate either with crowd astrophotography??? :D

The crowd images on astrobin by Morton Balling &Crowd (www.google.com/search?q=crowd+image+morten+balling +site%3A.astrobin.com)go for aesthetics&detail in assumed static DS objects, i.e. he uses images indiscriminate of their imaging date/year. But you would pursue a little more scientific approach and ensure images are taken within a given short time frame?

Which other parameters, other than DSO/area of the sky and time frame, would have to be met by uploaders? Would it be okay to upload stacked versions? Or do you think of collecting actual subs? Not saying "that can't be done", just trying to get more detail out of your dream.

[silv]

I can imagine several common dropbox-like accounts, upload-only for donating participants. An automatic notification email containing the link to the newly uploaded image which triggers an agent on the recipient's computer to start downloading for later stacking and processing.
If the given time frame were 1 week and the number of participants were, say, 150 per DSO/specified region of the sky (depending on the imaging goal to be discussed and decided in the committee :D ) - each recipient/admin of a dropbox would only have to manually handle 150 images (or the frames of 150 participants) per week (or per time frame set out in the committee).

Not too daunting a task for an individual, is it?

The next week, it'll be a different goal and a different group of stacking volunteers.

And the end results by each stacking volunteer can go up on Astrobin to a shared project account. To be used later for something else, like an all-sky-web-app Nick mentioned, or a scientific comparison with Hubble's successor, that imaging satellite, or something. Depends on the committee's vision.

[RickS]

https://petapixel.com/2015/05/27/this-telescope-uses-10-canon-lenses-worth-100000/