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In theory, it could work. You are talking about optical interferometry. There are optical interferometry projects in the professional astronomy world.

Applying it to amateur equipment would be beyond the financial capabilities of most amateurs. Interferometry relies on very precise timing and positioning data. Establishing the baseline data for an optical interferometer requires more precision than it does for radio telescopes because the wavelength is several orders of magnitude smaller.

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This really is a wonderful question but trying to set up such a system seems likely to be simply beyond our technical capabilities right now. And the expense appears to be unsustainable even for organizations with very deep pockets.

I think there was one of the bigger telescopes which was using two somewhat smaller scopes which were within dozens to hundreds of yards from the main scope in order to increase the effective resolution. The expense was just too much and they shut down one or both of the adjunctive scopes.

You would be talking about making extremely precise distance measurements from one telescope to another - and since tremors/earthquakes would tend to alter that you'd probably have to build a structure from each scope to several other scopes and be constantly monitoring the distance. I guarantee you will not be able to get the environmental impact statement cleared for that one. You'd have many, many governments incredibly upset with you.

You'd also have to develop and mass-produce professional-grade mounts which would be extremely precisely oriented and then calibrated and re-aligned regularly.

You'd have to be constantly monitoring the dust levels on the scopes and getting lights, darks, biases, and flats done on each scope - maybe at varying times through the night.

Focusing may have to be controlled centrally (not sure about that).

In order to get the timing right you might have to have an atomic clock located with each scope in order to ensure synchrony.

You'd have to ensure the power and cooling systems for all the instruments and may have to position a team at each site to maintain and operate the system.

Then you'd have to arrange for the bandwidth to transmit all the data to the central location (or to distributed computing locations) - we're talking a lot of data.

And once you got the data you'd have to have nightmarishly complex software. You'll need to understand things like atmospheric disturbance in the area. Be able to account for light pollution. Correctly process thousands to millions of lights, darks, flats, biases, etc. You'll have to figure out how to account for the person who is using a monochrome camera with one set of filters - while someone else is using a DSLR.

You'll also have to figure out how to handle different scopes using different sized sensors and different sensor orientations with different optics and figure out how to make them all point to the same part of the sky and frame that part of the sky in the same way. I hear of people getting frustrated with AstroTortilla - and this would look utterly nightmarish compared to that. What's more, you might have to default to the lowest common denominator as the standard for the imaging - which means folk using big expensive refractors and incredible imaging instruments which far surpass anything I could buy - might have to be dumbed-down to be the equivalent of my using a webcam with my ETX-80.

If you want an incredible nightmare the DSLR illustrates the problem extremely well. DSLRs have a big problem with mottling. So to do good work with DSLRs you dither - meaning that between each shot you move where you are aiming the sensor just a little. That means that every single sub done appropriately using a DSLR is going to be framed differently. That means that every shot of the sky will be in a somewhat different direction and you're somehow going to have to figure out how to handle that.

It might be fun to try something sort of like this in a small neighborhood - maybe some place like Chiefland (I think that's the name). Over short distances the problems are not as immense although they would still be very large.

But if you want to sort of dumb it down and do something better than the the professional scopes can do on a far more reasonable budget?

Join IOTA. Even with a small scope, a GPS video time inserter and a DVR and a few other things - you can work with IOTA to detect extremely close doubles, help to better understand Lunar geology, and get pretty precise outlines of asteroids (to start with).

You can also work on Jovian Extinction Events for a somewhat bigger budget to do some interesting research.

These things are nowhere nearly as complex as trying to build a large network of amateur scopes. The power is not the same as what you envision, but it still can do some pretty amazing stuff.

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The twin 10-meter Keck telescopes are a working example of large-aperture optical interferometry.

The cost and complexity of imaging interferometry are far, far beyond anything an amateur is likely to have, or be able to develop.

Among other things, one needs hydrogen masers, a precision beam-line over which the precise distance/time-of-arrival is always known and measurable, motion control systems with 10nm pointing precision, and both adaptive and active optics systems for coordinating and measuring wavefront distortion and timing on all the optical elements in the system.

You also need sodium laser artificial star sources for both focusing, and for the AO system.

The software, computing resources, and engineering skill sets to get this working, keep it working, and make sense of the data from the combiner is also substantial, rare, and costly.

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HagbardCeline said:

My main concern was that having them spread too far apart would change their vantage points and make it difficult to resolve.  On the other hand, this could give some images a bit of depth like a 3D camera.

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That is exactly the reason why you would want to do this in the first place The added value of the concept lies in the fact that the vantage points are so different.

But like you've found out through the astronomy forum, the exact two hurdles are mentioned are also recognized by the astronomers.

koraks said:

HagbardCeline said:

My main concern was that having them spread too far apart would change their vantage points and make it difficult to resolve.  On the other hand, this could give some images a bit of depth like a 3D camera.

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That is exactly the reason why you would want to do this in the first place <img src="https://files.shroomery.org/smileys/wink.gif" alt=";)" title=";)"/> The added value of the concept lies in the fact that the vantage points are so different.

But like you've found out through the astronomy forum, the exact two hurdles are mentioned are also recognized by the astronomers.

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