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A sensor is the digital camera's equivalent to film. It contains millions of tiny light-detecting areas called photosites, which convert light into an electric charge. After exposing the sensor to light, this charge is read from each pixel and converted into a digital image.

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78
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7answers
32k views

When do the differences between APS-C and full frame sensors matter, and why?

I'm trying to decide on a higher-end digital SLR, and I'm down to choosing between an APS-C model and a full-frame model. I understand that the sensors are of different sizes, and as such have an ...
48
votes
7answers
33k views

Can the sun damage the camera sensor? Under what conditions?

I want to experiment taking photos where the sun appears. I'm afraid of what might happen if I take one with a narrower angle (where sun would be bigger). Can the lens act as a magnifying glass and ...
27
votes
6answers
3k views

Do megapixels matter with modern sensor technology?

Are more megapixels good? Are more megapixels bad? Do more megapixels increase detail? Do they make my images sharper? On the other side, is there a point that is too much? Do megapixels cause ...
26
votes
6answers
10k views

Why does a bigger sensor lead to a shallower depth of field?

It has been mentioned at a few places that a larger sensor results in images with a shallower depth of field. Example image: APS-C Canon 30D left, FF Canon 5D right, same lens, same composition, ...
11
votes
5answers
2k views

How does taking lower-resolution pictures with a higher-resolution sensor affect image quality?

Does taking a picture with 8 megapixel resolution with my Canon IXUS with a 1/2.3" sensor and 12M max resolution provides the same or worse image quality (particular, noise) as if the picture was ...
26
votes
11answers
2k views

What is the best way to clean the sensor on a digital SLR?

I've got a couple of spots of dust on the sensor of my Canon 20D - a rocket blower isn't shifting them, and I'm ridiculously scared of some of the more direct methods for cleaning sensors -- what ...
17
votes
4answers
1k views

Does the dpi number reported by camera in JPG have any meaning?

I have two cameras, a 6mpix Panasonic FZ8, and 14mpix Canon A2200. When I compare shots from two cameras, one of differences I notice is dpi number that camera reports in JPG info: FZ8 reports ...
40
votes
8answers
16k views

What does “expanded ISO” mean?

The ISO specification for the Canon EOS 7D reads as follows: High ISO For handheld shooting in low light, the EOS 7D offers ISO speeds of up to 6400. Expandable to ISO 12800, for low light ...
20
votes
2answers
2k views

Why use a small aperture when trying to see sensor dust?

Here and there I read of people who set their lens to a small aperture while testing their sensor cleanness, supposedly to get the best image of dust speckles. However, the image of the on-sensor dust ...
15
votes
6answers
3k views

Why are blown highlights particularly bad in digital photography?

I've heard that digital sensors are less "forgiving" of blown highlights than film. Why is this? There's something called "characteristic curves". How does this relate, in film and in digital? Can ...
19
votes
3answers
4k views

What is meant by the “native ISO” when talking about DSLRs?

The new Nikon D7000 is out, and a lot of previews has touted the "native iso" of D7000 to be 100. What does this actually mean? I'm assuming it means it performs at its best at iso 100, which means ...
13
votes
4answers
4k views

When shooting in mRAW or sRAW, how does the camera generate smaller files?

Most mid- and high-end DLSRs offer two or three sizes for RAW capture. When the camera is generating the medium or small sized RAW files, how does it make them smaller? Does it capture less ...
6
votes
1answer
174 views

What characteristics make a digital sensor good?

Generally, the technical image quality of a digital image (before we get to the post-processing stage) is the product of the characteristics of the lens and the recording medium, with an important ...
4
votes
1answer
585 views

what's the relation between sensor size and image quality (noise, dynamic range)?

I'm reading this description on sensor size: Digital compact cameras have substantially smaller sensors offering a similar number of pixels. As a consequence, the pixels are much smaller, ...
22
votes
5answers
5k views

Why and how do “bigger pixels” make a better picture?

This is going off of today's iPhone 5S announcement, when Phil Schiller said that "bigger pixels" is the key to a better picture. What does this mean? Is it true or just a marketing ploy?
11
votes
3answers
840 views

What are differences between Bayer mosaic and Foveon 3 layer sensor?

To filling my appetite on camera things hunger I've came across to Sigma website and found this 3 layer sensor stuff. Can anyone really explain this based on their experience or research about this? ...
8
votes
1answer
4k views

How to fix an image sensor damaged by long sun exposures?

I took a number of shots of the sun during mid-afternoon and now all my images have pink spot where the sun was. Is there anyway to fix this, or is it permanently damaged? The camera was pointed at ...
20
votes
2answers
6k views

Why is a 1" sensor actually 13.2 × 8.8mm?

I'm wondering how sensor sizes are calculated. The Sony RX100 reportedly has a sensor size of 1" which is 13.2 x 8.8 mm according to the press release and various sites. How does that work? That's a ...
18
votes
2answers
622 views

What are the basic workings of the Lytro light-field camera?

lytro.com describes their new light field camera as being able to capture the entire light field, rather than just one plane of light, thereby allowing for a whole new set of post-processing ...
17
votes
2answers
4k views

What are the advantages or disadvantages of a back illuminated CMOS sensor?

The iPhone 4s uses a backlit CMOS sensor, and I have noticed that some other point and shoot cameras do as well. What does that mean for photography, and if it is a benefit why do DSLR cameras not use ...
15
votes
3answers
5k views

What is the Nyquist Limit and what is its significance to photographers?

The Nyquist Limit is frequently mentioned in the context of lens and sensor resolution. What is it and what is its significance to photographers? Here is an example of it being used by DPReview.com ...
9
votes
6answers
2k views

What happened to Foveon sensors?

It seems like the Foveon sensor should be able to produce better images, because it's not dependent on the separate red, green, and blue pixels as exist on most digital cameras. However, cameras ...
6
votes
1answer
4k views

What effect does UV filter provide?

I know that I should always use a filter on my lens to protect the camera lens, however, exactly what impact to the picture does using a UV filter have since that is the one most often used? Do I ...
10
votes
3answers
3k views

Should I clean my camera sensor, or take it to a professional?

Possible Duplicate: Best way to clean the sensor on a digital SLR? Can anyone offer me advice on how to clean my camera's sensor? Should I do this myself, or take the camera to a ...
9
votes
2answers
3k views

Why don't comparisons of aperture take sensor size into account?

When one compares focal length, many times we use the 35mm equivalent length. A 50mm lens on an APS-C sensor camera(1.6x) would be a 80mm equiv. length on a full frame camera. But when we state the ...
15
votes
4answers
7k views

Can a laser pointer damage the sensor in a digital camera?

I once experimented with standing in a dark room and directing a laser pointer towards my digital camera with a long shutter speed while moving the two about. I made a few images that way; one was ...
16
votes
7answers
611 views

Why do cameras use a single exposure rather than integrating across many very quick reads?

I have never understood why cameras need a shutter with a specific speed and why this cannot be adjusted in postprocessing. I think that present sensor works in an integral way: they save the amount ...
20
votes
6answers
4k views

How many stops can a digital camera capture?

How many stops can a digital camera capture? Additionally, does anybody know what the dynamic range is for negative and positive film, the human eye, computer monitor, the television, etc...
10
votes
2answers
3k views

What is “pixel density”?

Apparently megapixels aren't a good way to measure the camera quality, so some people are referring to a relative measuring system called "pixel density". What specifically is this? What information ...
4
votes
3answers
529 views

How linear are DSLR sensors?

To be more precise, let's say we are taking a W&B photograph. Picture 1 : And let's say we take it once with a 1/1000 shutter speed, so that the values for R/G/B range from 0 to MAXVALUE / 2 ...
7
votes
4answers
1k views

How many bits of data are typically actually captured by a digital camera sensor?

In a comment on this question someone suggested that camera sensors typically only output 12-14 bits of data. I was surprised because that would mean that 24 bits of color is only useful for doing ...
6
votes
1answer
419 views

Where is the AF sensor located in a DSLR?

As I understand every DSLR has a separate, smaller sensor that handles phase detection focusing. Where is it located? If this location is different for every DSLR, and therefore this broad question ...
5
votes
2answers
984 views

Is it sensor damage? Or dust?

I have been trying to shoot partial solar eclipse today with my Nikon D3100, and later noticed this spot on images: http://pix.academ.org/img/2011/01/04/70baea815d1557594f096a82ab05704f.png I do not ...
3
votes
2answers
436 views

Assuming a perfect sensor, what is the physical limit of ISO/pixel area?

Assuming that camera manufacturers can eventually make the perfect sensor that introduces no electrical noise to the signal, at what point (measured in ISO/area of a pixel) will shot noise be so ...
18
votes
3answers
3k views

Why are larger sensors better at low light?

The top answer of What point and shoots are good in low light conditions? says that (1) a fast lens/wide aperture (2) reasonable ISO 400+ handling and (3) a large sensor when put together are critical ...
17
votes
3answers
1k views

How can dynamic-range be larger than sensor bit-depth?

Found something that confused me and so I thought the crowd here can probably answer this one since its camera-related and technical at the same time. How can dynamic-range be larger than sensor ...
32
votes
4answers
7k views

What's the difference between CCD and CMOS image sensors?

I keep reading articles about CCD vs CMOS image sensors. What is the difference between these two types? What exactly do these sensors do in terms of photography? Is a CCD-based camera going to be ...
12
votes
4answers
872 views

Why is sensor sensitivity called “ISO”?

I was curious to know how the term "ISO" was coined for referring the image sensor's sensitivity. Is there any reason or circumstance that contributed for terming "ISO"? Also, does ISO has a literal ...
11
votes
4answers
4k views

What are the pros and cons of different Bayer demosaicing algorithms?

Bayer sensors use a pattern of red, green, and blue pixels, and merge those together into a final color image, with one pixel for every single color sensor. This could be done through a "naive" ...
13
votes
1answer
540 views

Is it really better to shoot at full-stop ISOs?

The second half of this answer says Notice that I only shot full-stop ISO which is important with Canon DSLRs because the gain to obtain the 1/3 stops in between is applied in software by the ...
8
votes
2answers
837 views

Why are sensors less sensitive to blue light?

This is a followup question to Why is the blue channel the noisiest?. The simple answer to that question is that sensors are less sensitive to blue, and therefore require more amplification, which ...
8
votes
7answers
1k views

Why has no one invented a 4:5 aspect ratio APS-C/35mm-sized DSLR?

People keep inventing different form factors and formats for cameras, but none seems to have hit on what seems (to me) like an obvious one. Why doesn't somebody build a camera with a sensor that has a ...
7
votes
4answers
1k views

Is a self-cleaning sensor necessary when using only one lens?

The Canon 1100d lacks a self-cleaning sensor. If I use this camera without ever exchanging the lens, is the absence of a self-cleaning sensor a bad 'feature'? Are the bodies of modern DLRS cameras ...
2
votes
2answers
545 views

Dust on the sensor, should I be worried?

I did a 30 second long shot without the lens and checked the sensor and saw some dust on my sensor (even though camera has sensor cleaning). I didn't see any defects on photos yet, but is it something ...
2
votes
1answer
608 views

Why does my Nikon D90 make a strange sound during built-in sensor cleaning, when my friend's D90 doesn't?

I noticed a quiet sound (like squeaking) when using the built-in sensor cleaning of my Nikon D90. In some forums I read about many people having this behavior with the Nikon D700 and some Canon ...
27
votes
6answers
2k views

Do sensors wear out?

We all know that shutters wear out and they have a limited number of actuation's. The question I have is, do sensors wear out too? Do they suffer any kind of damage after each shot? Should I be ...
12
votes
4answers
2k views

Is it risky or difficult to wet clean an image sensor?

I've discovered spots on the image sensor of my DSLR camera that cannot be cleaned using a blower bulb, so I would like to know the risk of problems, such as further image deterioration or damage to ...
12
votes
4answers
471 views

Are the sensors of newer DSLRs better beyond just having more MP?

I have a Canon Rebel XTI now, and am considering upgrading my camera body at some point. Aside from the increase in megapixels have there been other improvements to the CMOS sensors of the newer ...
12
votes
5answers
503 views

Does it matter which way the camera is orientated for the sensor cleaning to work?

With the advent of sensor cleaning in newer bodies - does it matter which way up you hold the camera whilst it is cleaning? I understand that the sensor cleaning works by vibrating the sensor to knock ...
11
votes
3answers
863 views

What advantages does a pure black and white camera have over colour cameras?

Now that Leica has released a pure black and white camera, the Leica M-Monochrome, I started to think about the advantages a pure black and white camera has compared to a colour camera. I guess you ...