Questions tagged [astrophotography]
Imaging of astronomical objects or large regions of the sky.
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Galaxy S4G database: convert pixel to kpc
I am referring to S4G database (https://irsa.ipac.caltech.edu/data/SPITZER/S4G/overview.html ).
The information on the length of galaxies, and various length parameters are given in terms of pixels.
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Why are certain stars not moving in this timelapse video?
In this video, certain stars are not moving in the bottom left & top right corners. I thought only the pole star didn't move.
https://www.youtube.com/watch?v=QC8iQqtG0hg&ab_channel=...
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Resolution: Telescopes vs. Camera Objectives
Telescopes and Camera Objectives are both optical systems which image objects from far away to a finite image distance. Although camera objectives are often used for finite object distances, in most ...
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Are there Wolter telescope lenses for consumer cameras?
Wolter telescopes are used for x-ray astronomy. However, I see no reason why they couldn't be used for visible light as well.
How would a visible image look when taken through a Wolter telescope?
Are ...
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Why do we see dark black spots in night sky with the naked eye if those same spots are filled with stars when looked at with a telescope?
When looking in the sky with the naked eye, we often see dark regions with no stars. However, when we look at those same spots with a telescope, it is full of stars or clouds of dust. Why is that?
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Pinhole camera as a device to develope photos of distant stars? [closed]
Could a transparent slab coated with photosensitive film be placed inside a pinhole camera nearly paralel to the path of the light emitted by a source of light(star) to produce a picture wich due to ...
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Can a photographic film on a flat slab create a well visible elongated picture of a far and faint astronomical object? [closed]
Let say we see a light source with apparent cross section area 1mm squared. If we position a flat slab with inductive high light sensibility at a very small angle to that source one dimension of the ...
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Considerations about a mathematically accurate calculation of astrophotography exposure times
Dear StackExchange community,
I hope this is the right place for my question. This question is motivated by the photographical topic, but is about a purely mathematical issue.
In astrophotography, a ...
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Could the black hole photo be a gravastar?
Mazur-Mottola gravastars would in many ways appear identical to black holes.
Does the new radio-photograph of M87* taken by the Event Horizon Telescope eliminate M87* as a gravastar candidate, and ...
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Why do stars appear so close in universe photos?
I saw an extremely sharp picture (from NASA/ESA) of the Andromeda Galaxy recently, and it made me wonder why the stars appear so close together, when I know in fact that they are not.
Is it simply ...
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How to make an image from telephoto lens smaller?
I have obtained an old telephoto lens that was adapted for astrophotography by the previous owner.
I have found a focal plane and I have placed a small webcam (without optics) there. There was a bit ...
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Using of optical slit for different spectrum
Here below the 3 spectrum currently used in astrophysics and illustrating Kirchhoff's laws (emission, absorption and continuous spectrums),:
I just want to know : what's the utility of the optical ...
user87745
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Actual Jupiter seen from the place, will it looks like on the pictures?
Jupiter picture processed by one of citizen scientists
Picture above is artificially proceeded by one of the citizen scientists working for NASA. It was composed from monochromatic pictures taken by ...
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Cameras in Voyager probes 2017 [closed]
Riffing off an old thread...
Analog v digital and data transmission aside, I'm wondering how images were captured in such low light at 37,000+mph. Seems like a wide open aperture and slow shutter ...
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What dynamic range is needed to photograph the moon and the sun in the same frame?
What dynamic range would in theory be required to photograph a total solar eclipse for real to get the effect on this commemorative stamp, with the moon illuminated by Earthshine:
For good measure, ...
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