Questions tagged [camera]
A device used to record static or moving images, either digitally or on a physical medium. The images captured may be in any region of the electromagnetic spectrum such as x-ray, infrared, visible, or ultraviolet and beyond.
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How to test the distortion of a Camera lens?
I have a camera lens and i want to perform the distortion test. I got some steps to perform it using Photo Diode and oscilloscope using a target. The step also states that after few steps i should ...
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How to reduce camera field of view (FOV)?
If I have a camera with a FOV of, say, 17⁰ deg, how can I limit that FOV to 1x1 deg? I imagine some sort of mask is what I am looking for, but what needs to be considered in designing a solution?
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How can I determine how much energy a sensor pixel can withstand before exploding?
I am trying to design a camera system to image a laser beam. I know the sensor is a Sony IMX226, and I have the data sheet for this sensor. The data sheet, however, does not list a maximum energy ...
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How to calculate the minimum distance where a USB cam provides sharp footage?
Can one calculate the minimum distance for a USB cam at which images appear sharp only from the focal length. Let's take this webcam from elpcctv as example.
The focal length is 2.8mm and the sensor ...
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Strange behaviour of ultra dark image in a CMOS camera? [closed]
Samsung Galaxy S21 Plus has a CMOS camera.
I recorded an ultra dark raw (DNG format) image using its Pro mode in the following conditions:
ISO 50
Shutter speed 1/12000
Cover the aperture with ...
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Vertical peaks in single slit diffraction pattern
I have the output from a single slit diffraction experiment using a HeNe laser (632.8nm), the diffraction grating is placed vertically so you expect to see only horizontal diffraction peaks in the “...
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How to calculate Distance $D$ to object from a camera with known $H$?
I am using algorithm to draw a bounding box around object when they appear in camera as shown in attached image. The main confusion is that i consider the object closer to camera when the Distance $D$ ...
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Can pixel color be used as s quantitative indicator of displacement?
This is regarding the use of pixel color to measure displacements smaller than the image resolution.
Say we have a glowing screen of uniform brightness shining at a camera. A curtain is drawn at ...
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Why does cooling down thermal imaging cameras increase sensitivity?
A lot of high-sensitivity thermal cameras and sensors are (cryogenically) cooled down to low temperatures to achieve these high sensitivities. For example. the Stinger missile, and the James Webb ...
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Is it possible to obtain noise level in electrons using only one camera?
In the link, https://www.photonstophotos.net/GeneralTopics/Sensors_&_Raw/Sensor_Analysis_Primer/Photon_Transfer_Curve.htm
there is one figured called Standard Photon Transfer Curve – Multiple ISOs ...
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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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Narrowness of black bars to be resolved by camera?
So the question is:
A digital camera has a lens with a focal length of 10 mm.
The image sensor, i.e. the photosensitive part of the
camera has 7.5 x 7.5 μm pixels. A test map with a variety
of ...
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Why doesn’t an irregular or polygon shaped hole work like a pinhole camera when held close to the screen?
When a card with a hole of any shape is held close to the screen, the lighted area on screen is of the same shape as the hole. To make an image of light source, say Sun, the card has to be moved away ...
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Can I able to detect (by long exposure shot) infra red region when black body is heated to its necessary temperature
When we heat a body ,it emits radiation in full spectrum with maximum spectral density at a particular wavelength depending on its temperature. When I heat the body to particular temperature , ...
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How to measure physical luminance just with regular camera? [closed]
Maybe there is some software for that task? Theoretically, it's able to realize. I guess it's may work somehow like bracketing in photography (making HDR shots from several shots with different ...
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Spatial Resolution and pixel smear and camera devices
Can anyone recommend a good source (video, textbook, online course) that I can use to learn more about spatial frequency, exposure, pixel smear, how cameras work. I only have some basic optical ...
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Cameras that can see through opaque objects
Are there cameras which can see through opaque objects (i.e. a reasonably dense curtain, cardboards or walls)?
And by see I mean in almost full color the way a regular camera would work.
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What if cameras get better than our eyes?
What happens when camera technology evolves so dramatically that (without considering zooming) camera lenses get “better” than our human eye?
Do we see the footage in higher definition, or do we ...
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How can a digital camera capture and render IR (and UV) light?
It is known that you can see IR with digital camera. I have personally tested with camera of phone and webcam with a RC of A/C. It is seen as mostly white light with red tint. I haven't tested with ...
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Weird pattern for a laser beam spot
I am trying to measure the gaussian profile of a laser beam, which is supposed to be T00. The profile shown in the specifications looks very Gaussian, and the laser is brand new. I am using this ...
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How our eye see real images formed by pinhole camera? [duplicate]
How do we(eye) see real image form in pinhole camera?
1.Are rays that are forming image pass through screen and reach our eye help us too see it ?
OR
Light rays from hole from where we are looking at ...
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How pinhole camera works? [closed]
What is the working principle of pinhole camera? What is the function of translucent screen in the camera? Now, if we look behind the translucent screen, what do we actually see: the image formed on ...
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Is it possible to use a distributed camera array to fake an interferometric sensor without phase data?
Astronomical interferometry is a technique which uses multiple small telescopes to mimic one giant telescope. It requires the phase of the light to be captured for it to work. It is widely used in ...
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Can there be multiple shot noise sources? For example: laser & camera
Suppose you have a system consisting of a laser, a filter (with transmission $T$), and a camera. To my understanding, both the laser and the detector produce shot noise. Is that correct?
For a camera ...
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Simulate a camera PSF?
Say I have a $3D$ object stored as a $3D$ $\texttt{NumPy}$ array in python. I want to view this $3D$ object as a camera would give: a particular aperture, focal length, etc. My understanding is I can ...
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Resolution of a Michelson Interferometer using a Webcam
I've built a Michelson interferometer which uses a webcam as screen. This setup shall measure and correct drifts in optical path difference of the two interferometer arms.
I have problems determining ...
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Is it possible to get a resolution that is better than what is given by the Rayleigh criterion?
I remember reading recently that it is possible to unblur a face that has been blurred by using a computer to process multiple images of the blurred face from different angles. This got me thinking, ...
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Does a thermal camera detect distant objects colder?
Thermal cameras are often calibrated and display the temperature color-coded in $^\circ$C and I wonder how that works...
A black body emits photons because of it's thermal energy. The hotter it is, ...
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Damage from the Sun on a Raspberry Pi Camera Sensor with a Fisheye Lens
I'm working on a CubeSat mission which uses two Raspberry Pi V2 cameras (without special filters) as sensors. I am trying to estimate if they could suffer thermal damage if they were to have the Sun ...
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Does the size of CCD/CMOS of a telescope affects the magnification?
For a normal, traditional telescope, the magnification level should equal to focal length divided by eyepiece diameter, i.e.,
$$Res=\frac{f}{D}$$
So does the size of the CCD/CMOS the same as eyepiece ...
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What's limiting the field of view of a lens
An ideal lens with finite aperture leads to the formation of an image in the image plane as
\begin{equation}g(x, y) = \int \text{psf}(x/\lambda d - x', y/\lambda d -y') f(x', y') dx'dy',\end{equation} ...
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Why do images not appear inverted when looking directly through a pinhole camera?
I understand that the way light takes through a pinhole creates an inverted image on a surface behind the pinhole. I remember this effect from school experiments, it's also described in this wikipedia ...
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Relativistic-speed cameras [closed]
I am asking on behalf of someone else. Here is their question:
Two cameras, each recording video at 500 trillion fps, are speeding toward each other at $0.6c$, on a direct collision course. When the ...
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What is the right camera lens for imaging this experiment?
I am conducting an experiment in our lab where we are using an ICCD camera to image a very short-duration (ns) physical phenomenon. The area of interest of the test is about 25mm x 25mm and I need to ...
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Why is the geometric spread and dispersion spread in a pinhole camera independent?
About 6:08 of this video, the equation for geometric spread($ x_{geo}$) is derived for a pinhole camera:
$$ x_{geo} = \frac{d}{s} (f+s) = d(1+ M)$$
Where,
$f$ is focal length
$s$ is subject length
$d$ ...
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Technical name (radiometric/photometric/ray-optic) of the physical field that is measured with a camera
A camera (that is FPA and objective) is a device that measures [intensity][1] or radiant intensity vs. two angles (horizontal & vertical). So it generates a representation of the physical quantity
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Relating exposure time of a camera to number of photoelectrons
How can we relate the exposure time of a camera to the number of photoelectrons created on the detector? We know the power and the wavelength of light hitting on the camera, quantum efficiency of the ...
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Can a curtain create a focused image on an opposite wall?
This video* (linked at the correct time of 0:26 sec) shows a scene inside a room of a home. Apparently projected on the wall is an imperfect but recognizable image of the outside street scene. The ...
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Type of camera that is used in a double slit experiment [closed]
I need to know the type of camera that is used in a double slit experiment. Both with photons, and that with electrons? Can someone please answer. The type of camera that is used for observation. Is ...
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How do single-pixel cameras work?
To obtain images using a single-pixel camera we need a Digital Micromirror Device (DMD) because single-pixel cameras only possess a single detector (article).
From my understanding, a single-pixel ...
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If image formed by a plane mirror is virtual, then how are we able to capture that in a camera?
What I have learnt in school is that, we are able to see images behind a mirror(virtual image) because our brain assumes that the diverging rays that our eyes see, are coming from a point behind the ...
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Specular Reflection of IR Light
I have started to use thermal imaging cameras more and more and realized that I can see the reflection of my self bouncing off of a glass window through the IR camera. When viewing it on my monitor, I ...
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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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Vision: eyes vs cameras
I think this is related to physics, and light waves.
Is there some materials that can be seen by human eyes and can't be seen by cameras? (Imagine a special writing) Is that even possible therotically?...
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Why hyperbolic shapes of colour distortion in this image? [duplicate]
I took a photo of my computer screen through my mobile phone camera. Why are these color distortions in hyperbolic shape?
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Limits of zooming in (for camera/telescope)
What limits the ability of a camera/telescope to zoom in on distant objects?
The question is twofold:
What zoom really is?
Firstly, I would like to gain clear understanding of what we mean by zoom ...
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Estimating the focus plane of camera via thin lens equation [closed]
I have a camera that outputs a JSON file for every image taken. In the JSON file, I can find camera-specific and also the photo-specific acquisition parameters used. The issue is I wish to estimate ...
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Understanding atmospheric transmission's effect on IR camera [closed]
I'm using an IR camera to view a person at 1 meter, and then 5 meters. When I view them at 5 meters the max temperature I see for them drops by about 1 degree Fahrenheit. I assume this is because the ...
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Difference Between Angular Resolution and Spatial Resolution of optical device (Camera)
As per wikipedia angular resolution is the ability of device to capture minute details of an object and is the same definition in case of spatial resolution.
Whats the difference Between Angular ...
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Why does a pinhole create an image of the Sun?
When I was a kid I happened to encounter a solar eclipse. I was taught that I should not look at the Sun directly when it is undergoing an eclipse, but I was extremely curious to see it.
Somebody ...
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