Resolution of observation telescopes?

In summary: If you scan a wide field, the energy flux is spread out over a larger area on the detector, so you need more photons to hit your sensor and create an image.
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LightningInAJar
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TL;DR Summary
Observation telescope stats.
I was wondering how the resolution is of a observatory station and compare that to its field of view? Higher rez with larger field or higher rez with more narrow field but much more scanning across the sky to create full images?
 
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LightningInAJar said:
Summary:: Observation telescope stats.

I was wondering how the resolution is of a observatory station and compare that to its field of view? Higher rez with larger field or higher rez with more narrow field but much more scanning across the sky to create full images?
I think your question could be based on a false dichotomy. You are not really comparing like with like. Resolution is not the only relevant factor in astronomy. Pushing the system to see (and resolve) as many stars as possible involves the good old Signal To Noise Ratio. Your two scenarios are including the implication that you want to scan a particular region of sky and not just to resolve two distant, faint objects. The diffraction limit is set by the diameter of the objective lens (at least, that's a major factor). If you use a long focus / narrow angle then your sensor can have bigger elements and, therefore more sensitivity to a given elemental angle of view.

But if you want to scan a wide field, either the focal length of the objective your sensor would need to be shorter and, to make use of this wider field, the element area would need to be less in order still to resolve the two faint objects and have room for many more on the image.

Otoh, you could stick with the original scope and scan it around. Apart from practical details, the longer time to get your big image by scanning the scope around would be very much of the same order as the extra exposure time you'd need to get high enough signals from your finer pitch sensor elements behind a wider angle lens.

That's probably a gross oversimplification but it's got to be based on the total Energy flux from each area of space onto a sensor.
 
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sophiecentaur said:
That's probably a gross oversimplification but it's got to be based on the total Energy flux from each area of space onto a sensor.
I think this can be shown, using information theory, to be exactlly true. Please don't ask me to reproduce the argument.... it would require deep coherent thought.
 
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Related to Resolution of observation telescopes?

1. What is the resolution of an observation telescope?

The resolution of an observation telescope refers to its ability to distinguish between two closely spaced objects in the sky. It is measured in arcseconds, with smaller values indicating a higher resolution.

2. How is the resolution of an observation telescope determined?

The resolution of an observation telescope is determined by its aperture, or the diameter of its primary lens or mirror. A larger aperture allows for more light to enter the telescope, resulting in a higher resolution.

3. Can the resolution of an observation telescope be improved?

Yes, the resolution of an observation telescope can be improved by using adaptive optics, which corrects for atmospheric distortions, or by using a technique called interferometry, which combines the light from multiple telescopes to create a larger effective aperture.

4. What is the diffraction limit of an observation telescope?

The diffraction limit of an observation telescope is the theoretical limit to its resolution, based on the wavelength of light being observed and the size of its aperture. It can be calculated using the formula: θ = 1.22 * λ/D, where θ is the angular resolution, λ is the wavelength, and D is the diameter of the aperture.

5. How does the resolution of an observation telescope affect its capabilities?

The resolution of an observation telescope directly affects its ability to observe and study objects in the sky. A higher resolution allows for more detailed and precise observations, while a lower resolution may limit the level of detail that can be seen. It is an important factor to consider when choosing a telescope for specific research or observation purposes.

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