What is Camera: Definition and 304 Discussions

A camera is an optical instrument that captures a visual image. At their most basic, cameras are sealed boxes (the camera body) with a small hole (the aperture) that allows light in to capture an image on a light-sensitive surface (usually photographic film or a digital sensor). Cameras have various mechanisms to control how the light falls onto the light-sensitive surface. Lenses focus the light entering the camera, the size of the aperture can be widened or narrowed to let more or less light into the camera, and a shutter mechanism determines the amount of time the photo-sensitive surface is exposed to the light.
The still image camera is the main instrument in the art of photography and captured images may be reproduced later as a part of the process of photography, digital imaging, photographic printing. The similar artistic fields in the moving image camera domain are film, videography, and cinematography.
The word camera comes from camera obscura, which means "dark chamber" and is the Latin name of the original device for projecting an image of external reality onto a flat surface. The modern photographic camera evolved from the camera obscura. The functioning of the camera is very similar to the functioning of the human eye. The first permanent photograph was made in 1825 by Joseph Nicéphore Niépce.

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  1. C

    Heat signature of security camera

    Is it possible to use a thermal imaging camera to detect the heat signatures of a security camera? Are you familiar with any equipment which can detect its electrical, electromagnetic or metalic signatures? You might wonder why I'm asking. It's because I'm a bachelor degree student in...
  2. Artlav

    Pinhole camera optimal resolution?

    For a given pinhole size in a camera, and camera size, what would be the optimal pixel size to get the maximum resolution at maximum light intensity? i.e. the larger the hole, the more light enters through it, but eventually the sharpness would drop below the resolution. Conversely, the...
  3. A

    What camera is an iPhone 4s using?

    Omnivision? Or developed by apple itself?
  4. Andy Resnick

    Lytro Camera: Understanding Focus After Image Acquisition

    For those who don't know, a company (Lytro) just released a camera that allows for changes in focus *after* the image was acquired. Now that's it's been released as an actual product, I'm intensely curious to understand how it works. Their website has a cutaway image, and the 'lightfield...
  5. J

    Computer Vision Geometry - Collinear Points In A Pinhole Camera Model

    Homework Statement Prove that a line in 3D space is imaged to a line on the image plane in a pinhole camera model. Homework Equations A 3D point give by (X,Y,Z) will be imaged on the image plane at x = f(\frac{X}{Z}) and y = f(\frac{Y}{Z}) where f is the focal point. The Attempt at...
  6. A

    Calculation of torque for motion control camera arm

    Hi, First post here, but I've been reading the forums for a while getting answers for various projects. I am currently working on a lightweight motion control camera arm (kind of a small jib arm, but with servo actuators). I've researched a lot to figure out what force I would need in...
  7. V

    Would amateur be able to take the flash out of a disposable camera and

    ...set it up in some kind of circuit in which I can press a button/ hit a switch and have the flash go off? I need to create and electric device of some sort, and seeing as I have a bare minimum supplies, I thought this may be plausable. I also need to draw circuit diagram to this. I am...
  8. B

    Infrared and NIR Camera Sensitivity

    Problem: I'm trying to optimize an inexpensive digital camera with a CCD sensor for NIR video. As of right now (after removing the IR filter) it doesn't work well in the dark at all (even with a basic visible light filter ... obviously). I have to direct at least a little bit of regular light...
  9. J

    New Video on One trillion frames per second camera

    New Video on "One trillion frames per second camera" Here is the video: Mods, please delete if there is already a thread for this. I think this is a great achievement by the researchers. It's an interesting topic, so maybe people can use it to ask questions on how/why it works, and...
  10. fluidistic

    Tips to buy a new digital camera?

    I've a digital camera since 2005 and it started going bad maybe 1 or 2 years ago. Basically most of the time when I want to take a photo it turns automatically in filming mod. I have to wait/shake the camera in order for it to turn back to photo mod and that's pretty annoying; even more...
  11. Pengwuino

    Digital Camera control software?

    So I'm taking a bunch of pics at regular intervals to show my class how this borax/glue slime slowly collapse and spread. This happens over the course of a few minutes and it gave me an idea. Is there any software out there that you could hook up your digital camera to and have the software take...
  12. M

    Calculating Object Height Using a Pinhole Camera

    I don't have any idea how to go about this... Please help!:frown: A pinhole camera produces an image of an object kept at a distance of 100m from the pin hole. If the screen is 10 cm from the pin hole and the image is 5 cm high, what is the height of the object Any help will be...
  13. D

    Angular Acceleration of Camera

    Homework Statement http://imageshack.us/photo/my-images/855/10544781.png/ Homework Equations a=[r''-r0'^2]er+[r0'' + 2r'0']e0 where 0 = theta The Attempt at a Solution stumped about it, I've tried setting the above to 0 then work out r which is 200 m but that's just cluelessly...
  14. C

    How does the iphone 4s camera work?

    Many people use the iphone nowadays. But I wonder if they know exactly how it works? I found a description of the technologically advanced iphone 4s camera features, and I curious as to how it works. The lines in red are what I found from the apple website. The iPhone 4S camera gives you 8...
  15. K

    Axis Camera with I/O and relay to turn on lights

    Hi, I do not know anything about relays. I been trying for days to hook up a relay to turn on a light using an Axis camera with an I/O switch. This is the relay http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&itemSeq=105585863&uq=634536768231996536&DPU=submit This is the manual...
  16. J

    A camera falling from a blimb

    A camera falling from a blimb... pleasezzz help (part 1 of 2) A camera falls from a blimp that is 349 m above the ground and rising at a speed of 17.2 m/s. Find the maximum height reached by the camera with respect to the ground. The acceleration of gravity is 9.8 m/s^2 Answer in units of m...
  17. W

    Using a zoom camera to identify object and laser to track

    Hey You may have seen the mosquito killing laser system from the intellectual ventures lab. In the description of the system they say the zoom camera identifies an object (mosquito) and from that they are able to direct a green laser on it and track it. What I am wondering is how the...
  18. Saladsamurai

    Going to Ghana Need Camera Suggestions

    Hello folks :smile: My girlfriend and I are leaving on September 14 for a 6-week humanitarian effort in Ghana, Africa. We organized the trip through a group called http://villagevolunteers.org/" . The DSLR is amazing and we will definitely be bringing it with us. What we are looking for, is...
  19. V

    Camera near the speed of light

    If you were infinitely close to the speed of light, and you attempted to take a picture of yourself, would it work? Would there be any way to make it work using relative velocities?
  20. P

    Diffraction and Aperture Size: How Does It Affect Image Resolution?

    Hi there, I understand somewhat how diffraction works in terms of the aperture of a camera lens and the resulting loss in resolution in the image, but my question is: Is the degree of diffraction only dependent upon absolute aperture size, or the size of the entrance pupil? For example, f/22...
  21. Andy Resnick

    Vacationing with a Camera: Nashville and Beyond

    A quick post before heading out on vacation: Thanks to everyone with their advice on getting through TSA screeners- there was no issue at all. Here's a few shots out the window- daytime: http://img687.imageshack.us/img687/4154/74592845.jpg and sunset...
  22. C

    Why are moving objects blurred in a camera?

    Forgive me if I'm missing something truly basic about photography, but I always wondered why camera photos appear blurred if the object's moving fast. Isn't the speed of light large enough where, even if the object is moving rapidly, the time it takes to reach the object is negligible compared...
  23. L

    Lunar Rover Equipped with HD Video Camera

    I want to know why someone hasn't built a 'rover' of some sort that could easily navigate the lunar surface while recording HD video. I don't think funding would be an issue since you could easily strike a deal with a large company pertaining to product placement i.e. a coca-cola bottle in the...
  24. L

    Pinhole camera question with only two known variables?

    Homework Statement True or False: If a pinhole camera casts on the screen an image of 40.0cm in size of an object situated at a distance of 40.0m from the camera, then the size of the object is 10.0m. Homework Equations M = hi/ho = di/do The Attempt at a Solution hi = 40.0cm do...
  25. M

    Radar Camera for Large Format Photography

    Large Format Photograph Machines usually uses 8x10 inches size negative. Can I make a radar large format camera with using similar or bigger size plate as antenna and when transmitter was a cw radio transmitter ? I know only need of mixing transmitted to received. If this does not work , can...
  26. M

    Designing a digital eyepiece camera

    I have an optical design question - hopefully this is the right forum in which to ask. It is "engineer", but it's really optical engineering... --------------------------------------------------------------------------------- I am wondering if someone can help me out here with a few...
  27. S

    What can you capture with an IR camera using heat transfer principles?

    Hello, i have a college seminar due 1 week from today and our group has already done the writing part of it, but now we need to take a few pictures with the IR camera itself and we are clueless what to actually shoot because the idea must be innovative and simple and must be backed up by heat...
  28. P

    Camera Calibration: Estimate Lens Distortion from 1 Photo

    Hello, Here is my problem: I've created reference pattern for camera calibration. It consist of well defined dots where each dot is unique. What I'm trying to do is to estimate lens distortion from only one photo. I can easily identify dots on photo, but I have no idea how to estimate the...
  29. T

    Find out How Long 9.5 W Battery Can Run Camera

    Homework Statement How long the camera can be operated in the 9.5 Watts recording mode using an initially fully charged battery. P = 9.5 W, V = 7.2 V, I = 1.3194 A Homework Equations (Cb) = I x t The Attempt at a Solution (Cb) = I x t = 1.3194 x 3600 = 4749,84 minutes...
  30. S

    Programming a video camera for a noob

    Hello everyone, I have a basic (I think) question about how a consumer video camera is programmed to do what it does. The camera I have in mind is the Flip (may it rest in peace). Ok, so I'm aware of most of the parts that go into a video camera, such as the shell, controls, lens, sensor...
  31. L

    Troubleshooting a Coil Gun Project Using a Disposable Camera Circuit

    I'm making a coil gun for a project, and ran into a few problems. I used a circuit from a disposable camera, which had a capacitor and charging circuit. I used two wires attached to the capacitor to connect the circuit to my solenoid. However, after charging the capacitor, nothing seems to...
  32. H

    Laser Split Into Camera Lens Pattern: What is it?

    What is the pattern made of balls? https://www.youtube.com/watch?v=KrUhKQxOPx0 I have some hypotesis: Something related to the CCD, a diffraction pattern caused by some dirt on the lens, or, but i think it's absurd, the Bravais lattice of the lens? I'm very curious!
  33. T

    Problem concerning zoom lens in camera

    Problem concerning zoom lens in camera... This problem deals with a diverging lens placed to the right of a converging lens. The converging lens has a focal length of 12cm and the diverging lens has a focal length of -12cm. The lenses are separated by 4cm. a) For a distant object, where is...
  34. A

    Why Does Camera Flash Brighten Stars in the Sky?

    When I point a camera at the sky and use the flash, it brightens up all the stars I'm looking at (not just the ones on the screen). Does anybody know why this is?
  35. S

    Rocket Camera, CMOS vs. CCD

    I'm looking for a small camera to use in my rocket. It's about a 7' rocket, 4" diameter and 3" long viewing window. I've heard that the choices are either cmos or ccd but I don't know the difference between the two. I'm only looking to spend up to $100 (really looking in the $50 range). Any...
  36. Andy Resnick

    Insights Digital Camera Buyer's Guide Introduction - Comments

    Andy Resnick submitted a new PF Insights post Digital Camera Buyer's Guide Introduction Continue reading the Original PF Insights Post.
  37. E

    SAXSess from Anton Paar (Small angle x-ray scattering camera)

    Is there any user on this forum who have used the SAXSess? please reply to this post. I need some discussion.
  38. Andre

    Which Camera to Buy? Advice for Photographers

    That question comes up every now and then. So maybe it's an idea to unanswer that here in this thread. So you want to be able to make those nice pics you see in the nature books, commercials etc. Obviously you need good equipment for that. The first essential thing is brain, the most...
  39. B

    How can I convert 18v cordless drill battery to recharge laptop, compact camera?

    I have 2 rechargeable 18v battery pack from cordless drill which I'm thinking of using as laptop charger and compact camera battery charger. These packs comes with 220v adaptor. Me and my 12yo son will be doing a week-long research for his school project (climate change) this Xmas break...
  40. G

    Automated Camera Clicking: Get Your Ideas Here!

    Camera "clicker" I need to take a picture every 5-60 seconds for about 2.5 hours. The problem is, I won't be near my camera when I do that. I want to make something to attach to the "clicker" or whatever it's called on the camera that will click it about that often. The button definitely...
  41. S

    Mirror or Camera: Which is the Truest Reflection of Our Perception?

    Which one is a more accurate representation of the image? (i.e. what we see with our own eye) I've read that camera's actually flatten out the 3d image, but I have no clue what the consequence of this would be, while I do know that mirrors flip the image but I think that's the only thing that...
  42. DaveC426913

    Stole memory card from my camera?

    stole memory card from my camera?? I've been working tech support at a conference all weekend. I went to use my camera this morning and found the SD card missing. I know that, when I took 50 pix the day before the conference, the card was in there (I would not have been able to take pix...
  43. edward

    Google Street View Camera Vehicles Collected WI FI data

    Google claims it was totally inadvertent that they collected wi fi data using their street view camera vehicles. Personally I can't bring myself to believe that. http://www.pcmag.com/article2/0,2817,2363835,00.asp This was first revealed May but for some reason is just now hitting the...
  44. F

    Therefore, the drum rotates 142.97 times before coming to rest.

    High speed cameras are used to photograph events which take place too quickly to be seen by the human eye. One such high speed camera is composed of a rotating film drum, a rotating shutter and some miscellaneous optics. The film is fastened along the outside of the drum (along its entire...
  45. A

    Whats the price of Thermographic camera?

    Hey what's up. How much will be the price of a Thermographic camera, I am thinking in doing something like spy operations(yeah i know I am kinda crazy bla bla). Also what's the name of the technology that let you see trough walls? it is infrared?
  46. Evo

    Using Kodak DCS 520 Camera: Advice & Tips

    I'm thinking of using the Kodak DCS 520 I inherited. It's still in the original box and never been opened. Has anyone used it or something similar? How dificult is it to use? I'm a bit camera phobic. It's old in terms of digital cameras, but it's just sitting there and I'd like to take...
  47. M

    Is the Olympus Stylus Tough 8010 a good digital camera option?

    Hi, I'm after a digital camera. Doesn't have to be too special beyond a) a high resolution (12MP minimum) and b) reliable and likely to last a while. I'm looking into this - Olympus Stylus Tough 8010 14 Megapixel Digital Camera - Silver 5X Optical Zoom - 2.7 LCD Touch Display - Waterproof -...
  48. L

    Where can I find comprehensive coverage of Vidicon television cameras?

    Homework Statement my textbook material on vidicon television camera is inadequate and i would like to know some web links from revered members which could provide some exhaustive coverage of vidicon. could members provide the link? Homework Equations The Attempt at a Solution
  49. N

    Mathematical relationship to control camera heading

    Hi everyone, I want to find a mathematical relationship between my head direction and the direction of a camera placed at a distance. The objective is to make the camera heading to same point where my head is looking at. Both my head and the camera are in the horizontal plane and the motion...
  50. M

    What is a high resolution CCD camera suitable for inspecting metal cavities?

    Hi, I'm trying to find a high resolution ccd camera that can be used to take PHOTOGRAPHS to inspect the surfaces of metal cavities. It has to be compact and oblong to fit into a tube so it can be inserted into a cavity. I'm looking for something very much similar to this shape...
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