36

Firstly the iPhone 5 lens has to be f/2.2, due to the small pixel size, the effects of diffraction which start to creep in at f/11 on a DSLR, start to creep in at f/1.45 on a 5.6mm (diagonal) sensor! I though that in order to have a big aperture such as f/2.2 a big amount of light should be able to enter to the sensor and in order to do it, a big lens was ...


26

The 12MP designation is usually used to refer to still photography while the 1080p designation refers to video. The sensor has 12 megapixels - sometimes a little more which gets masked out. This means it takes 12 megapixel photos. Most likely this is a 4:3 aspect-ratio image which means about 4000x3000px. Video is a stream of images, most commonly ...


24

Most times it's because putting the lens in the center would require unacceptable design compromises. The average camera-equipped smartphone has a large, flat battery just behind the back cover. Putting the camera in the middle would require splitting the battery or manufacturing one with a hole in the middle, which would get very expensive.


18

1080p refers to video: 1920×1080 progressive scan. The phone is capable of 12 Mpixel still images but only 1080p video. (This is fairly typical; it takes a lot more processing power to take video at a given resolution than to take a still at that resolution.)


14

I disagree that the location of the camera is counter intuitive. When I am using my phone(using a wallet as an example here), I hold it in the palm of my hand - exposing the upper corner of where the camera is naturally. This is the way that I normally shoot images with my smartphone. If I am typing, I use two hands, but the same corner is still exposed ...


14

You should shoot with your phone - best way to get better is to shoot more, which is great if you already enjoy it. But you should get a dedicated camera if you're interested. They work differently than phones and will let you learn about stuff like focal length, white balance, aperture and shutter speed and why they matter. My recommendation - buy, ...


12

Facebook images are usually displayed at around 720×540 pixels. That is about one third of a megapixel, so for that use, anything you can buy is overkill in terms of megapixels. This is perfectly fine for almost all online display, and will even make decent small-sized prints. However, megapixels do not accurately represent image quality. The answers to Why ...


12

Yes, it is possible - however, a quick experiment shows that it's a little tricky and that the results aren't as good as what you can from a bigger camera. The bokeh discs are just out of focus lights - so all you have to do is place some lights and "defocus" them. Here's what you do: You need an iPhone 3GS or later, earlier models are not capable of ...


12

I initially assumed that the reason to the skew faces was a result of curvilinear properties of the lens, but JohannesD pointed out in the comments that it could be due to rectilinearity itself since the corners get "stretched". Unfortunately both of these explanations causes skewness but they are different kinds. Without an image as an example I'm ...


12

There are a lot more to image quality than resolution (i.e. number of megapixel). First of the light from the subject has to be gathered to the image sensor. This is done by one or several optical elements that together constitutes the lens. These elements can differ in quality and a low quality lens will not produce a high quality image no matter the ...


12

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 camera. The same sensor does not necessarily mean equal pictures. The sensor is one component of the whole process - the others are the analog-to-dicital-...


10

To take a digital picture you need: Optics Sensor Image processing (CPU and algorithms) As you see, sensor is just a one link in a chain, and the chain is as weak as it's weakest link. Currently, we are experiencing great technological progress in the third stage. Compared to DSLRs, smartphones have abysmal both optics and sensors - however the ...


9

F values are relative to the focal length; the absolute aperture size of an f/2.2 lens is 1/2.2 times the focal length of the lens. Cellphone cameras have tiny sensors and thus large crop factors - their focal lengths are typically only a few millimeters. Even with a large relative aperture the absolute size of the aperture is only a millimeter or two.


8

The white paper in your link explains this very nicely. The "jiggery-pokery" that Engadget speaks of is not faking the high resolution, but rather going the other way around: the sensor really does appear to have that many tiny little photosites, but under normal use, it pixel bins. (Presumably, the image quality is pretty atrocious at the pixel-peeping ...


8

Disclosure: I'm the guy behind Cine Meter and Cine Meter II, so take what I say with a grain of salt, grin. Do these apps really work, or are they gimmicks? They really work, within the limits of what the built-in camera allows. They may not be able to measure really dim light, for example. Can they get the same information from a scene that a real ...


8

There's a bit of a bug in the way Motorola set up the camera profiles on the RAZR (and many other phones in the same family, all of which use a near-identical load of Android) that causes images to be compressed a lot more than they should be. The problem can be corrected by rooting the phone and making some minor modifications to a configuration file. How ...


8

One could achieve similar starbursts by holding a Star-16 filter (such as Cokin A055 or P055) in front of the camera phone lens. During a photoshoot aimed at demonstrating the camera's capabilities, however, the director of the shoot should consider that it's not what many phone photographers would do, so it would still count as deception.


8

Instead of trying to describe it by mere words, I'm posting this to show the size of those bokeh balls. They are quite small, as you can see. Bright ones are made of several overlapping "balls" but some dim ones appear individual. Actually all background blur is made of these circles, but only those created by a point light come up visible. Photo taken with ...


8

Megapixels just tell you one thing: the number of individual tiny detectors on the sensor. They do not tell you anything about: the size of the sensor overall the sensitivity and size of each sensor the ability to read from the sensor without introducing noise other technical aspects of the sensor construction (back side illuminated? standard Bayer array or ...


8

It's highly unlikely that this many pixels on the sensor would become "dead" in quick succession, or in this pattern (groups of pixels, rather than individual pixels). This is clearly dust directly on the sensor. I also see indicators of dust on the inside of the lens (larger, out-of-focus areas that are lighter than their surrounding pixels). For ...


8

Looks really bad. Normally, dust gets on top of the stack of optical filter which sits above the sensor. It then shows as small blurry disks which get smaller and darker at narrow apertures because they are close to the sensor but not directly on. From your example, I would guess that you have dust that entered below the filters and is directly on the ...


8

Why does it seem like large sensors are necessary for good low-light performance? Because for the same amount of light passing through a lens a larger sensor will collect more of it. Your tire size analogy is seriously flawed. A better analogy would be increasing the diameter of the engine's cylinders. The size of the individual molecules of the fuel/air ...


8

Camera phones don't have variable apertures (apart from a handful exceptions) because they are not designed like full sized cameras. Owing to their tiny size, decreasing thickness of phones in general and the ever present cost-vs-complexity challenge, they have a fixed opening/aperture. If the bundled camera app doesn't provide you any option to change the ...


7

The QX10 and QX100 aren't actually lenses for your phone, they are a miniature point and shoot camera that uses your phone for control and display of the images. (Think of it kind of like a remote controlled digital camera with no screen.) It has its own sensor and is basically the same as buying a point and shoot that copies the photos to your phone. ...


7

With phone cameras it is as much about the computational things done to it after the raw data is collected from the sensor as it is about the hardware specs. You can certainly use hardware bad enough that no amount of computational photography will overcome it. But by and large most of the hardware used in upper tier phones is good enough. It's often how ...


6

Quote from www.exif.org/dcf.PDF (Design rule for Camera File system): With the rapidly growing popularity of digital still cameras, there are increasing demands for file interchangeability, which will allow images captured on one camera to be viewed on another, or output directly to a printer. ExifR98 is a set of compatibility recommendations ...


6

First, make sure your camera is set to highest resolution and quality supported, the galaxy S2 has a 8 mega pixels camera but it can also be set to take lower resolution pictures, down to 640x480 (0.3 mega pixels) and at that low resolution the pictures are really mostly unusable. I believe what you call "dotted" is noise, the way to reduce noise is to have ...


6

They key factor about Nokia's new PureView camera in the Lumia 920 is the optical image stabilization. From what I understand, Nokia put in a lot of R&D to develop an optical image stabilizer to be paired with their 8.7mp sensor. From the marketing hype, they were claiming it was capable of a degree of stabilization that rivaled that present in DSLR ...


6

Yes there are many ways the starburst diffractions effects could be achived with a fixed f/2.0 lens: Photographing the image projected by an SLR lens onto a groundglass. Products to achieve this used to be very popular with indie filmmakers to allow shallow depth of field (before the 5D mkII came along). Effectively provides the same image as you'd get with ...


6

The actual focal length of the lens is usually measured along with the crop factor of the sensor. Cell phones, needless to say, have a huge crop factor. For example, the Samsung Galaxy SIII and iPhone 4 are a 7.6x crop. So, if you have a 5mm lens on one of those, you're looking at an equivalent full frame focal length of 38mm. That's wide, but not that wide.....


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