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Old 24-04-2016, 00:01   #1
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Cestial navagation by camara?

Is there effort in using a camera to monitor stars, or celestial objects, identify them, and then measure them for the celestial navigation module?

The price of cameras has gotten rather low recently, so something should be affordable?
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Old 24-04-2016, 00:08   #2
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Re: Cestial navagation by camara?

Drat! I thought you were asking about how to use the tonka-bean tree to navigate.

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Originally Posted by ViribusUnitis View Post
Is there effort in using a camera to monitor stars, or celestial objects, identify them, and then measure them for the celestial navigation module?

You could try a mobile device, such as an Android tablet, loaded with an app such as Stellarium (see https://play.google.com/store/apps/d...are.stellarium) or similar app.


In truth, the accuracy of such apps relies on the mobile device having a GPS/GNSS fix and (for best performance) a fluxgate compass. And if you've both of those, why would you then work out the celestial fix?
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Old 24-04-2016, 00:24   #3
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Cestial navagation by camara?

Are you asking if is possible, then yes plenty of folks using a camera as a sextant. If you want to read about it the NavList folks have several threads on the topic: http://www.fer3.com/arc/sort2.aspx?s...1401&y2=201912

Your individual camera and lens would need to be calibrated and you will need software that can give you x,y coordinates for individual pixels. I use Paint on Windows machine so that's not so hard to come by.

If you are asking if someone has automated the process in an app, the no, not to my knowledge.


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Old 24-04-2016, 00:35   #4
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Re: Cestial navagation by camara?

What about using something like a fish eye lens on a high resolution security camera? Mount the camera somewhere pointed straight up, with a clear view of the sky, from horizon to horizon. Maybe an UV-VIS-IR camera to have the best chances of seeing the bodies through thin clouds?

If you wanted to be clever, add a digital gyroscope, and a fluxgate to the system.

The goal would be to have an automatic system that would continuously monitor the visible bodies, identify what they were, measure them, and then calculate position. If it was automated, a cheap CPU should be able to do the calculation for position at nearly real time. Throw in the fluxgate and the gyroscope, and you'd only need one star identified, and no need for a visible horizon.
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Old 24-04-2016, 00:35   #5
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Re: Cestial navagation by camara?

Played with a few photos in the past. It could be a goer with the right software
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Old 24-04-2016, 00:47   #6
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Re: Cestial navagation by camara?

This one shows both the Moon, an unknown star or planet and a slightly fuzzy horizon. It is reasonably clear, but with no magnification I dont know how accurate it would be. It was taken on a samsung G7 on the west coast of Tassie heading up to Port Davey. I was very impressed with the low light capabilities. It seemed much darker by eye.
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Old 24-04-2016, 00:49   #7
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Re: Cestial navagation by camara?

Fisheye creates 3 problems, bigger chunck of the sky is spread across the same number of pixels on the sensor so resolution is compromised, fisheye decreases light sensitivity so stars are missed in marginal conditions and the fisheye creates a very distorted image so calibration would be a long involved process and there would have to be some sort of coordinate mapping in the algorithm. Not impossible but one more large issue to program into the app.

The flux gate would help you some with star identification but the gyroscope won't do anything for you. To be useful it would need to be accurate to 1 arc-min. That's DoD or NASA accuracy not iPhone accuracy. Horizon works much better and a phone could probably be programmed to recognize it.


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