52
votes
Accepted
Canon geometric overexposed quadrilateral shapes in all of my images
It looks like you've got a problem with the shutter. Possibly one of the "blades" in the second curtain is missing and allowing light to strike the sensor between the time after the second curtain has ...
- 175k
50
votes
What would be causing a thick black diagonal line in front of my camera's sensor?
From what I see this is element from the shutter. And my humble advise is to send your camera to repair shop, give it in to the hands of professional, do not try to repair it.
- 11.5k
47
votes
Accepted
What's the point in covering the viewfinder?
On SLR cameras, the optical path is connected to the viewfinder. Even while a picture is being taken and the mirror is up, blocking the viewfinder path, it's possible the seal/gasket between the ...
- 32.3k
42
votes
Is it true that the best images from all digital cameras can be obtained at ISO 200?
There is an ISO which is not necessarily 200 that is the native sensitivity of the silicon from which the sensor is made. That sensitivity depends on the sensor itself, so will vary between cameras, ...
- 103k
40
votes
Accepted
Why don't cameras offer more than 3 colour channels? (Or do they?)
Why don't cameras offer more than 3 colour channels?
It costs more to produce (producing more than one kind of anything costs more) and gives next to no (marketable) advantages over Bayer CFA.
(Or ...
- 4,770
40
votes
Why do photos with different settings produce different spots?
Let me just complement Xenoid's answer.
In this diagram, you can see how a bigger aperture produces a diffused shadow, that sometimes is hard to see.
And when you use a smaller aperture, the shadow of ...
- 23.8k
34
votes
How many pictures can you take with a Sony mirrorless camera before the sensor fails?
Unlike a mirrored camera, there is little likelihood of the sensing system
in a mirrorless camera suffering a catastrophic failure so it is really up to your "taste" to determine when a sensor is too ...
- 1,989
32
votes
Can the sun damage the camera sensor? Under what conditions?
At very wide angles the danger is much less and taking photos with the sun in the field of view doesn't normally harm the camera or lens. When the sun is very low on the horizon the energy is also ...
- 175k
28
votes
Accepted
Signal to Noise Ratio over the years
This data was iffy then — not really enough data points, and the trendline is dubious:
Source: a very timely xkcd
That said, the company DxOMark does measurements of camera sensors all the time, ...
- 143k
28
votes
What causes these squiggly lines in my photos and on my sensor?
Looks like fungus on the sensor (possibly under the low-pas filter). Some examples:
https://www.flickr.com/groups/canondslr/discuss/72157604712577076/
https://www.dpreview.com/forums/thread/3556906
- 20.6k
24
votes
Accepted
Is it true that the best images from all digital cameras can be obtained at ISO 200?
The information your friend gave you was essentially correct for most digital cameras, particularly compact digital cameras with very small sensors, made about 15-20 years ago. Digital imaging sensors ...
- 175k
23
votes
Why do cameras use a slit between two curtains rather than exposing the entire sensor instantly?
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 ...
- 12.9k
23
votes
Why do electronic shutters expose row by row?
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 ...
- 31.7k
23
votes
Accepted
RAW files store 3 colors per pixel, or only one?
Raw files don't really store any colors per pixel. They only store a single brightness value per pixel.
It is true that with a Bayer mask over each pixel the light is filtered with either a Red, Green,...
- 175k
23
votes
Why do photos with different settings produce different spots?
This is typical of sensor dust, the spots are more visible at small apertures. In fact taking a picture of the sky with a small aperture (large f-number) is the usual way to check for dust spots...
So ...
- 20.6k
21
votes
Why do cameras use a slit between two curtains rather than exposing the entire sensor instantly?
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 ...
- 1,848
21
votes
What would be causing a thick black diagonal line in front of my camera's sensor?
The item obstructing the sensor is a shutter blade. Your shutter has failed and needs to be replaced. There's no hack or DYI solution for this problem. This is a hardware problem and not something ...
- 674
20
votes
Accepted
What are physical causes of clipping?
What exactly limits modern digital camera sensors in capturing light intensity beyond certain point?
In terms of the physical properties of the sensor itself:
The number of photon strikes and the ...
- 175k
19
votes
Why don't cameras offer more than 3 colour channels? (Or do they?)
A few notes from this long-time optical systems engineer. First, there are things called "hyperspectral" cameras which use gratings or equivalent to break the incoming light into dozens or ...
- 1,887
19
votes
Why doesn't digital Large-Format exist?
It depends on how you define camera. In a sense, digital large format does exist, just not exactly in the way we might expect.
There are commercial products called 'Digital Scanning Backs' that fit ...
- 175k
19
votes
Why should we be interested at incident metering?
You said:
What is important is the subject being well-exposed to the sensor.
Exactly – you've hit the nail on the head.
Imagine photographing a bride and groom. The groom has worn a black suit and ...
- 11.7k
18
votes
How to build an attachment to support lens?
I am using a D5200 and wish to find the height of the centre of the sensor from the base of the body.
I don't know the number, but you should be able to measure the distance easily enough. It's a ...
- 31.7k
16
votes
Accepted
Hot, stuck, or dead pixels. What's the difference?
Excitingly, these terms mean different things to different people. I think the most useful distinction is like this:
Stuck pixels are always completely bright, as if they're fully overexposed
Dead ...
- 143k
14
votes
Accepted
Why is the IR filter present when there is already the Bayer filter on an image sensor?
The Bayer filter passbands are designed to be make the sensor have a reasonable match to the human eye, while not costing too much. They're fairly leaky even in the visible part of their stop band, ...
- 3,772
14
votes
Why don't cameras offer more than 3 colour channels? (Or do they?)
RGB camera sensors are so popular because they reproduce human vision
That's what most people need - making photos that look like what we see.
Replacing RGB subpixels with more different kinds of ...
- 5,045
14
votes
Why are camera sensors green?
An unfiltered CCD or CMOS sensor looks very similar to any other silicon integrated circuit that has a very regular/repeating structure of similar structure size - semi-metallic gray (from silicon, ...
- 7,182
14
votes
What causes these squiggly lines in my photos and on my sensor?
This is too long to post as a comment:
In a past life I've looked at many silicon wafers under a microscope with various stacks of deposited thin films and while I can't say so definitively, the ...
- 1,827
13
votes
Accepted
What camera companies make their own sensors?
The underlying technology is broadly the same for all sensor makers and is the same technology used to produce other chips (such as CPU's). Manufacturers tend to be coy about where a chip was made (...
- 9,539
13
votes
Can smartphones with the same camera sensor have different image quality?
Note: This is a simplified answer. It does not go into detail, and therefore, please do not take it as authoritative answer on specifics about the exact processes that take place inside a digital ...
- 6,467
12
votes
Would APS-C be better for shooting wildlife?
Crop sensors are indeed used for wildlife to get more reach without sacrificing megapixels. And, you can get closer images without spending as much money. Sure, you could crop, but then your printing ...
- 466
Only top scored, non community-wiki answers of a minimum length are eligible