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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Would Jupiter seen from near the planet itself, looks like it does in pictures?
Jupiter picture processed by one of citizen scientists
The picture above is artificially processed by one of the citizen scientists working for NASA. It was composed from monochromatic pictures taken ...
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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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Clear Pictures from a Distance
How are astronauts able to take high resolution photos of small objects on the Earth's surface while traveling at 25,000 feet per second without the image being blurred?
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Nonlinear Response of CCD camera
What is meant when it is said a CCD's response is nonlinear? Does it mean the value of a pixel of the camera is not proportional to the number of received photons? Does it involve saturation? What ...
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Photographing the night sky - How important is fixed alignment of the camera?
If I set up my long exposure camera on a tripod and point it at the sky at night with the pole star in the centre we get a lovely image of concentric circles or arcs of circles depending on exposure ...
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How do we get images of galaxies?
First of all a very basic question upon which my main question is based. "Are the pictures of milkyway galaxy we see on books/mags are real ? ". If they are real then my question is, how we have taken ...
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How do we determine the pressure at the surface of a star?
Is there any means to do so?
I know there are some means to determine the surface temperature.
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Raw data acquirable from amateur astrophotography
What raw data can I possibly acquire from an 8" Classical Dobsonian Telescope, and a DSLR? Could anything eye-opening to amateur astronomers be computed or calculated first-hand with such equipment? I'...
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Land proportions in NASA blue marble photographs
What is the explanation for the apparent size difference of North America in these two photos from NASA?
Image source
Image source
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How do we know what the Milky Way looks like?
There is no way (with the current technology) that we could send a probe outside the Milky Way in a reasonable amount of time. So, how do we know what the Milky Way looks like, and what factors do ...
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How can we take pictures of something billion of light years away?
I have had this question in my mind for a long time, I thought you guys might enlighten me easily.
I am confused about some space photographs and claims like "this galaxy is 13 billions light years ...
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How did they take photos of Jupiter?
How did they take photos of Jupiter - I mean Jupiter is illuminated and that's a lot of light to produce. Am I missing something, and there was some sort of dark photo technology used, or was there ...
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Non-uniform lens flares [duplicate]
I assume -- and maybe wrong -- that lens flares, in photography, are caused by light getting "trapped" inside the curved lens and bouncing around (due to refraction and non-perfect total internal ...
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Why Can We See Stars In The Sky
Why is it when we look up into the night sky we can see stars. but when you see pictures taken from the ISS you don't see any stars. Why is this?
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What Causes the Noise Floor of Modern CCDs?
CCDs are getting pretty good these days, but all systems are subject to noise. A typical value for a CCD seems to be 20 electrons RMS per pixel. This article from qsimaging.com says
CCD Read ...
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Aligning images of starfields
I have two images taken within 30 minutes of each other in the same part of the sky. They are very similar but are slightly offset due to the Earth's rotation and other factors.
I know: the X, Y ...
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Why do astronomers never put a scale on their photographs?
Why do astronomers never put a scale on their photographs? I have been looking at images of the Bird nebula, a collision of three galaxies, but in none of the dozen or so that I have found, nor in the ...
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If the observable universe keeps expanding would we eventualy see light 24/7.... clouds permiting? [duplicate]
If we can see more observable universe could there be a time when day and night looked the same?
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Does an uneven and/or moving surface affect quality when using a solar filter?
I have chosen to make my own solar filter using Baader as opposed to Mylar or anything else based on these: https://physics.stackexchange.com/a/25204/6805 and http://irwincur.tripod.com/...
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What sort of equipment would I need to take a photo like this?
I'm interested in doing some astrophotography and I'm looking into the equipment needed to get a photo like this: http://www.flickr.com/photos/cscunha1984/6619321531/in/faves-heyvian/
I'm not looking ...
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Quality loss when adding more components to a telescope?
I would think this would be inherently true, but I'm curious:
(Assuming the highest quality amateur instruments are used.)
Is quality lost when, say, adding a T-mount adapter, diagonal or any other ...
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Celestron NexStar 6 SE vs. Orion XT8 [closed]
I'm interested in purchasing a new telescope and have narrowed it down to the NexStar 6 SE vs. the Orion XT8.
I'd like to be able to get into astrophotography and read that having the Go-To (auto-...
Trent Scott
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How to get started in Astronomy (UK based) [closed]
I have always been interested in space and astronomy (in my youth - I wanted to be an astronaut).
However for various reasons, I never quite got started. I now want to get started - small but ...
voidstar
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Can the "Milky Way" galaxy be seen by the naked eye in a clear sky?
Is this photo "real"? Are the stars not super-imposed in the image?
Ian
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What do the colors in false color images represent?
Every kid who first looks into a telescope is shocked to see that everything's black and white. The pretty colors, like those in this picture of the Sleeping Beauty Galaxy (M64), are missing:
The ...
Patches
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When taking a sequence of exposures for stacking/coaddition, what dither patterns are most commonly desired? Why?
When taking a sequence of exposures for stacking/coaddition, what dither patterns are most commonly desired? When visiting a telescope, what default dither patterns would a visiting astronomer like to ...
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Where can I find public domain astronomical pictures?
Where can I find public domain astronomical pictures of nebulae, stars, etc. that can be freely used?
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Exoplanet surface detail: Limitations on size of space telescope array
How big could an array of space telescopes acting as an interferometer be ?
How big would it have to be to resolve exoplanet surface detail the size of Iceland at a distance of 100 light years ?
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