23

As was said, the mechanical shutter has speed limitations. As to the slit, try to imagine without it. Suppose the shutter opens by moving from top to bottom of frame. And then of course, it has to close from bottom to top. So it is open longer on the top side than on the bottom side, which is uneven exposure. Modern fast curtains might move about 7 ...


22

So, why can't the sensor's image data downloaded to the processor, globally? Why is it downloaded row by row? It's a matter of physical limitations and simplicity. The physical limitation is that there's only space for a certain number of external connections -- you couldn't possibly connect every pixel to the processor and grab all that data at once ...


21

Thought experiment time. Assume we'd like a minimum exposure of 1/2000 of a second (500 microseconds) on a 35mm full frame camera. We have a single 'shutter' to move out of the way, and back. We'll tolerate one side of the picture being 10% more exposed than the other, so that means we allow 50μs to move the shutter back and forth. So the shutter has to ...


18

You are correct that the image is inverted as it is projected on the sensor and that the mechanical shutter reveals the bottom of the scene before the top of the scene. What you have missed is that the image (with the shadow of the cork falling on the red shirt at a later time than the the actual cork is seen flying through the air) is not a still frame ...


14

The rolling shutter is a method of image capture which is not by taking a snapshot of the entire scene at single instant in time, but rather by scanning across the scene rapidly (vertically or horizontally). The implications of using a rolling shutter can produce predictable distortions of fast-moving objects or rapid flashes of light such as wobble (jello ...


11

I think you've slightly misunderstood how the shutter works. Initially, the first shutter covers the sensor and the second does not. The first shutter then slides away to expose the sensor, and the second shutter follows it to cover the sensor again. The shutters always move at the same speed, regardless of the exposure time. For a short exposure, the ...


7

Most DSLRs have shutter curtains that transit the face of the sensor in approximately 2-4 milliseconds. For any particular camera model, barring a mechanical malfunction, the transit time for each shutter curtain will always be the same, regardless of the exposure time. This is the case with shutter times anywhere from 1/8000 second, where the second curtain ...


7

Yes, you are right, the effect is opposite from what we would expect from a shutter moving downwards. And this is because the shutter moved upwards, or, more specifically, it was the electronic shutter so nothing really moved, but the image data was being read from top to the bottom of the image (which corresponds to the bottom-to-top of the image sensor). ...


7

Very early color reconnaissance cameras did, in fact, use a color wheel in front of a camera with B&W film. At that time the resolution available with B&W was superior to that of color film. Developing labs that could easily process B&W film were also already in place at the air bases from which such cameras were flown. The resulting images were ...


6

Because the sensor essentially never stops sensing. There is no mechanism built into the sensor to not bleed charge from the little capacitors when light hits it. It also takes long enough to read out all the data from the sensor, so that there would be significant exposure time variation between parts of the image if the firmware reset the sensor, waited ...


5

This is caused by the lightning illuminating the sky very briefly as the photograph is captured. The image on digital cameras is not recorded on the whole sensor at the same time, but instead it scans across the sensor, usually (as in this case) parallel to the shorter edge. It is particularly pronounced on camera phones as the scanning speed is slower than ...


4

Satellite photos are often taken that way, with multiple linear sensors ("push broom scanners") that each detect different frequencies, mounted in such a way that they pass over a given point on the planet's surface at slightly different times. If it's an aerial shot, that's weird.


4

Simply because there's only so fast a mechanical thing can accelerate out of the way of the sensor (or film) and back without causing severe engineering issues with timing and diminishing shutter lifetime. It's simply not worth it when the alternative has no disadvantages in most uses.


4

The primary question is, "Why do smartphones use CMOS instead of CCD sensors?" Due to the way they are wired, CMOS sensors read out sequentially. This results in rolling shutter type artifacts. CCD sensors, on the other hand, dump the information from each pixel simultaneously into a buffer which is then read out while the pixels are capturing the next ...


3

There is no global reset on all pixels simultaneously. This is the Holy Grail of sensor design that hopefully may come soon. Canon, in order to save cost, does not include a mechanical first curtain in your RP. Electronic first curtain is just a row by row read that ignores the result by dumping the charges. That row will start accumulating charges again. ...


3

It is still the same shutter, even in long exposure and pixels are not exposed simultaneously. However, the time difference (in relation to the total exposure time) becomes smaller as the exposure time increases. It might become insignificant depending on your requirements. If you cannot tolerate rolling shutter at all, you still have 2 options: use ...


3

This is a prime example of the so-called "rolling shutter" effect. It happens in some devices (like this phone) that do not have physical shutters and have to expose the image line by line. What's observed here is an image exposed from top to bottom, i.e. the top part of the truck trailer was exposed a certain amount of time earlier than its bottom part, ...


3

Modern DSLR cameras come with rolling shutter. My Nikon has visible rolling shutter (in certain conditions). I don't know whether exceptions exist. Yes, this site says that CMOS have a rolling shutter and CCD uses total shutter. Here is a search showing all cameras with a CCD sensor. Here is the same search but showing DSLR cameras only. There are no ...


3

You seem to be confusing the time it takes to expose the sensor that is the time each pixel well on the sensor collects light information and the time it takes to readout the sensor that is the time it takes to collect the information that each pixel well has recorded. If I have a shutter speed of s-seconds, then does it mean that the camera takes s-...


2

The reason is economical. CMOS sensors with global shutter are available, but the added complexity makes them very expensive, and this extra cost would be justified for very, very few photographers. Let's take Sony video camera models PMW-F5 vs. PMW-F55. Global shutter is the main difference between them. The price difference is quite steep, $16k vs $29k - ...


2

I would print a straight vertical line and attach it to a turntable set to 45rpm. IF you set up the camera so that the frame covers the centre to the edge of where the record goes you can then measure the effect by the bend in the straight line, and compare different cameras even if the focal length changes.


2

CMOS sensors almost all use a rolling shutter, CCDs are generally necessary to get a global shutter. It has to do with the way the sensor is read. A CMOS sensor by design has to be read in series and thus creates a rolling effect as values are sampled. The main way that a few specialized sensors get around this is by including memory with each pixel to ...


2

Shutter rates, as measured by Jim Kasson - blog.kasson.com typical mechanical shutter 1/250 Nikon Z6 1/37 Nikon Z7 1/16 Nikon D850 (full) 1/15 Nikon D850 (crop) 1/40 Sony A9 1/150 Sony A7RIII (normal mode) 1/15 Sony A7RIII (continuous mode) ...


2

For the purpose you describe: Yes, all pixels are exposed simultaneously; they work independently, in parallel. Even for the short periods of time at start and finish, they're still all working together - but the shutter will need some time to get out of the way completely. So if a short event were to happen during the long exposure, what you will get is a ...


2

CMOS pixels are reset and then gather the cumulative charge from the light they receive until they are read & reset again. The CMOS is usually reset, the shutter process takes place (front curtain, delay, then rear curtain) and then values are read. Because of the mechanical process, there will always be a short period during the shutter opening/...


2

The newest update to that announcement is from two months ago: "Panasonic unveils 'industry-first' 8K organic image sensor with global shutter", as the article mentions they have a prototype and Apple has bought a competing technology - since this idea has been floating around for a half dozen years I'd expect it will be a few more until it's available/...


2

Flickering was the unavoidable effect of the image display method in CRT displays and therefore it was always synchronized to the frame rate. In today's LCD screens there is no connection between flickering and the refresh frequency, because it's not the screen what flickers, but its backlight. (this also means that unlike CRT, some LCD screen will not ...


1

I think if you read the manual you will find that the electronic first curtain/mechanical second curtain function is only available at SS's below shutter curtain transit time/flash sync (~ ≤ 1/250). And at higher SS's it is functioning as a completely electronic shutter... which is rolling readout, not global. The rolling readout electronic shutter works by ...


1

That's because the curtains of the shutter have limited speed. So if you want to archive high speed/small time of exposure you need to keep sensor exposed to light for short time. And in such case is simplest not to increase the speed of curtains, but to limit the size of the slit For example if the size of the sensor is 24mm and the flash sync speed is 1/...


1

For me it looks like rolling shutter effect. For more detailed explanation what is this you can check here


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