What is megapixel?
Basically your mobile camera captures images as pixel elements, known as pixels. Simply put, a megapixel is equal to one million pixels. Digital images are made up of thousands of these tiny, tile-like picture elements. The more pixels, the higher the image resolution. Resolution relates primarily to print size and the amount of detail an image has when viewed on a computer monitor at 100%.
Why more pixels isn't always better
If you bought a high-end smartphone last year, 8 megapixels were standards. This year the number increased to 13 and you can bet 20 megs would rocket to the market soon. The technology moves forward and I'm not saying you shouldn't follow, but make the conscious choices rather than follow the masses and the advertisements.
The number of megapixels is only one aspect relating to the quality of the camera, or the actual quality of a photo it is capable of producing and its not the most important one, even though the phone makers would like you to think so.
Factors such as an optical quality of a lens, light and image sensor and the software that translates data onto a visible picture play much more important roles. In short, the formula for really good quality photos comes down to the entire camera module.
That's why even if a 13-megapixel smartphone camera sounds great, an 8-megapixel shooter could still produce better pics.
That's why even if a 13-megapixel smartphone camera sounds great, an 8-megapixel shooter could still produce better pics.
What happens when you press shutter key on your camera? The light enters through the camera lens, then passes to the camera sensor, which receives the information and translates it into an electronic signal. From there, the image processor creates the image and fine-tunes it to correct for a typical set of photographic flaws, like noise. Let's check the important components of the camera module. |
1. LENS
As in the the world of the professional cameras, one of the most important element of the camera deciding of a quality of the picture is its lens. Despite of their tiny sensors of 1/3.2″, lenses are the work of art and not everyone can manufacture them to the respectable quality. That's why NOKIA for example entered agreement with Carl Zeiss to get the highest quality lenses for their camera phones. |
From the left: complete camera assembly - CCD sensor - lens in an autofocus assembly - optical lens on the right
2. IMAGE SENSOR
Second most important ingredient in the optical system is the sensor, because that's the part that captures the light. The sensor is essentially the "film" material of a digital camera. No light, no photo.
The size of the image sensor is extremely important. In general, the larger the sensor, the larger your pixels, and the larger the pixels, the more light you can collect. The more light you can catch, the better your image can be.
Second most important ingredient in the optical system is the sensor, because that's the part that captures the light. The sensor is essentially the "film" material of a digital camera. No light, no photo.
The size of the image sensor is extremely important. In general, the larger the sensor, the larger your pixels, and the larger the pixels, the more light you can collect. The more light you can catch, the better your image can be.
Because our smartphones are beautifully slim these days, there is no room (like in dedicated digital cameras) for large sensors.
So what manufactures do? They compensate by making pixels smaller and cramming more of them, on the mostly unchanged size of the image sensor. What's happening is that the light would go into the well and hit the photo-sensitive part of the image sensor, capturing the light. So if you make the wells smaller, the light has a harder time getting to the photo-sensitive part of the sensor. In the end, moving up the megapixel ladder without increasing the sensor size can degrade the photo quality by letting in less light than you could get with slightly fewer megapixels. Only Sony addresses this drawback, having 20 megapixels camera but putting considerably larger sensor inside their new Xperia Z line phones. |
To get better quality of our pictures we need the better chips not more pixels. OmniVision (picture above) might have the right solution. They come out with a new, RAW-capable CMOS sensor for mobile phones. Shooting in RAW means that no data is lost when your phone converts the image data from the CMOS into a JPEG, so it should improve image quality… especially given the OmniVision sensor maxes out at 5 megapixels.
With their flagship model HTC one (now we have the second incarnation of this phone based on the same principal, despite of the second camera), the company successfully challenges the myth of megapixels by demonstrating that less is actually better in many circumstances. It has 'only' a 4MP sensor, but that should be put into the context though: the camera has a smaller sensor but much larger pixels to allow in more light, and therefore more data, to make your pictures look much better especially under not perfect light conditions.
HTC claims that it enables each pixel to capture more than 300% more light than most leading 13 megapixel cameras. The Ultrapixel method (as HTC calls it) is one to be applauded, as it's pushing back on the 13MP image sensors that are being crammed into ever-thinner phones these days.
If you need more info of how ultrapixels work go to: HTC BLOG
The relationship between the number of pixels and the physical size of the sensor is why most 8-megapixel cameras can easily outperform 12-, 13-, or 16-megapixel smartphone cameras.
If you need more info of how ultrapixels work go to: HTC BLOG
The relationship between the number of pixels and the physical size of the sensor is why most 8-megapixel cameras can easily outperform 12-, 13-, or 16-megapixel smartphone cameras.
3. IMAGE PROCESING
The fallacy of megapixels
You can start to see that cramming more pixels onto a sensor may not be the best way to increase picture quality. However up to a certain point, megapixels do matter and relate to image quality - if you intend to print your photos. If you only enjoy your photos on your computer screen, or uploading to a photo or social network sites to share with friends, you really wouldn't need more than 3-5 megapixel camera for the nice size of the picture and some cropping corrections.
If yo do intend to print you photos, 5 megapixel camera gives you 10×8 inch prints without loosing any quality, which is most what people want. Printing big size posters require many more megapixels to achieve the quality, but I can't imagine you would use your camera phone to do this instead of dedicated cameras.
You can start to see that cramming more pixels onto a sensor may not be the best way to increase picture quality. However up to a certain point, megapixels do matter and relate to image quality - if you intend to print your photos. If you only enjoy your photos on your computer screen, or uploading to a photo or social network sites to share with friends, you really wouldn't need more than 3-5 megapixel camera for the nice size of the picture and some cropping corrections.
If yo do intend to print you photos, 5 megapixel camera gives you 10×8 inch prints without loosing any quality, which is most what people want. Printing big size posters require many more megapixels to achieve the quality, but I can't imagine you would use your camera phone to do this instead of dedicated cameras.
Final words
Why do camera makers keep making cameras with many more megapixels every year? The answer is simple. They need a reason to convince us in the public that the next model we buy will be a big upgrade from the recent one.
So, what is the lesson to be learned from all of this? Megapixels are great. They brought digital photography out of the dark ages and allowed photographers to make digital images that compare to film images. But megapixels are no reason to upgrade your current smartphone.
Why do camera makers keep making cameras with many more megapixels every year? The answer is simple. They need a reason to convince us in the public that the next model we buy will be a big upgrade from the recent one.
So, what is the lesson to be learned from all of this? Megapixels are great. They brought digital photography out of the dark ages and allowed photographers to make digital images that compare to film images. But megapixels are no reason to upgrade your current smartphone.
Different approaches
Very fortunately, we've reached the stage where the number of megapixels in the camera phone, simply doesn't improve the image quality and cannot justify spending money on a new phone (though Sony with their Xperia Z1 thinks differently). So it's time the manufacturers need to think of a new, refreshing approaches to further enhance the pictures quality in the smartphones. Here are the several promising examples of the technology I pay close attention to, hoping for better tomorrow.
Nokia's PureView
Nokia's PureView technology first presented in Nokia 808 and then implemented into Nokia Lumia 902 and 1020 is an interesting and fine exception, from what I've said about megapixels, because it actually uses the numbers of the megapixels to achieve very specific goals, instead of being an advertisement tool.
Even though Nokia has engineered the 808 to capture up to 41 megapixels, most users will view photos as the 5-megapixels default.
Usually, when you use the digital zoom on your phone, to crop some elements or bring closer look at someone for example, all you see is grainy, blocky, and not always as sharply focused or as colorful scene as you'd wish to have.
In the 808 PureView, Nokia uses a process called "oversampling," which - for the 808's 5-megapixel default resolution - condenses the information captured in seven pixels into one (they call it a "superpixel.") If you zoom in on an object, you're simply seeing part of the image that's already there, rather than scaling it up. This method translates to higher-resolution digital print-outs and zoom-ins than you'd normally achieved using a standard camera phone.
Usually, when you use the digital zoom on your phone, to crop some elements or bring closer look at someone for example, all you see is grainy, blocky, and not always as sharply focused or as colorful scene as you'd wish to have.
In the 808 PureView, Nokia uses a process called "oversampling," which - for the 808's 5-megapixel default resolution - condenses the information captured in seven pixels into one (they call it a "superpixel.") If you zoom in on an object, you're simply seeing part of the image that's already there, rather than scaling it up. This method translates to higher-resolution digital print-outs and zoom-ins than you'd normally achieved using a standard camera phone.
It's taken Nokia's over five years to create this technology. Not only does the 808 lean on the physical size of the sensor (specifically 1/1.2-inch), which is an unusually large not only in the smartphone standards, but it's also larger than sensors found on the vast majority of point-and-shoot cameras, but there are also custom algorithms on top of the sensor to adjust the image to reduce noise imperfections. Its also worth to mention that the next models of nokia's phone, 920 and 1020 use very advance OIS (optical image stabilization) to give you the perfect shots. If you would like to dwell into this technology go to: NOKIA PureView imaging technology that explains it in detail.
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Pelican imagining
Another very promising technology, I was paying close attention to, is a combination of clever hardware/software solution.
On 01 may 2013 Nokia and Qualcomm invested combined $20 million in the company called "Pelican Imagining". This very fact deserves to be taken seriously.
On 01 may 2013 Nokia and Qualcomm invested combined $20 million in the company called "Pelican Imagining". This very fact deserves to be taken seriously.
So what this fuss is about?
The value of this technology, lies in the Pelican’s software at least as much as in its hardware design.
Pelican’s CEO, Chris Pickett, describes his company’s invention as “fundamentally different” to anything else. Not only does it have 16 lenses, it effectively contains 16 separate cameras providing 16 streams of data, which Pelican’s software interprets into one single image. These sub-cameras share some key components, but the fact that they are isolated from each at the point of image capture, allows for some amazing photographic abilities.
First and foremost, the 4×4 grid of sub-cameras creates a ‘plenoptic’ system that captures an ‘image’ (albeit not a viewable one, at this stage) representing many different focal planes simultaneously. Once the software has worked its magic, user can choose which part of an image they would like to focus on with their fingers on a cellphone or tablet, allowing them to edit different people or objects separately without damaging their surroundings, or what Pickett describes as “Photoshop-level editing, non-destructively.
Pelican’s CEO, Chris Pickett, describes his company’s invention as “fundamentally different” to anything else. Not only does it have 16 lenses, it effectively contains 16 separate cameras providing 16 streams of data, which Pelican’s software interprets into one single image. These sub-cameras share some key components, but the fact that they are isolated from each at the point of image capture, allows for some amazing photographic abilities.
First and foremost, the 4×4 grid of sub-cameras creates a ‘plenoptic’ system that captures an ‘image’ (albeit not a viewable one, at this stage) representing many different focal planes simultaneously. Once the software has worked its magic, user can choose which part of an image they would like to focus on with their fingers on a cellphone or tablet, allowing them to edit different people or objects separately without damaging their surroundings, or what Pickett describes as “Photoshop-level editing, non-destructively.
In other words, you can focus the image after it has been taken without loosing any quality. When shooting 1080p video, the camera could even correct for camera wobble separately at each plane of movement, offering powerful digital stabilization.
Secondly each sub-camera captures just one color — red, green, or blue — instead of trying to cope with all three. This reduces “color cross-talk” interference and hence, Pickett claims, delivers better image quality in low light than any existing smartphone camera.
Secondly each sub-camera captures just one color — red, green, or blue — instead of trying to cope with all three. This reduces “color cross-talk” interference and hence, Pickett claims, delivers better image quality in low light than any existing smartphone camera.
Finally, replacing the traditional need for focusing could make photography much easier and offer a level of creative freedom that was previously limited to much larger contraptions, such as the Lytro camera (another plenoptic product). But this approach also has a major benefit for manufacturers: the absence of a focus system means that Pelican’s camera has no moving parts, making it “half as thick as state-of-the-art competitors”, as well as bringing it into the normal realm of costs, estimated at between $18 and $20 per module.
Now, this is where the business angle comes into play, because all these photographic capabilities have one thing in common: they require vast amounts of computing power. |
That fact alone is enough to explain why Qualcomm is a keen backer: above all, a chip maker of that size depends on consumers seeing a genuine reason to upgrade to smartphones or tablets containing the latest and most expensive processors. Pelican’s software is designed to exploit every part of a cutting-edge Snapdragon 800 mobile chip, from the CPU to the GPU and even the DSP, and indeed Qualcomm is already flaunting a reference tablet that has a functioning Pelican camera built into it.
By now, it should also be clear why Nokia wanted to secure itself a stake in the Pelican Imaging adventure. Having manufactured the PureView 808 with a ground-breaking 41MP camera sensor, and the Lumia 920 with sophisticated “floating lens” stabilization, the Finnish manufacturer is banking on camera hardware to help sell its coming generations of phones. Pelican has already confirmed that its system could work in tandem with PureView designs, yielding some “pretty exciting possibilities.”
In fact, the real question for me is why, Nokia used its investment arm — Nokia Growth Partners (NGP) to claim a stake, rather than just snapping up the entire company as it recently did with Scalado, another imaging-related startup?
In fact, the real question for me is why, Nokia used its investment arm — Nokia Growth Partners (NGP) to claim a stake, rather than just snapping up the entire company as it recently did with Scalado, another imaging-related startup?
Sony camera lenses
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Another smart idea that I've been personally waiting for, for a long time. Sony’s unusual Cyber-shot QX10 and QX100 lenses are designed to turn any iOS or Android device into a professional point-and-shoot camera.
Designed to be mounted onto a smartphone for a sleek, distinct look. Users can then pair the camera with their smartphone over NFC, using their normal handset as a live viewfinder. Being able to detach the lens has another advantage. You don't need it to be physically connected to the smartphone to use it. Your smartphone is the control interface, but the lens itself has a zoom toggle, shutter button and a front control ring around the lens barrel. That means you can easily shoot in tight spaces or at awkward angles, watching the live view on your phone. |
The body of the lens accommodates a battery in the rear, as well as a microSD card for onboard storage. There's a Micro-USB connection for charging as well as a screw thread for a tripod, so you could quickly position it using your phone as a remote control from a distance.
The QX100 has a 20.2-megapixel Exmor R CMOS sensor, the same found in the critically acclaimed Cyber-shot RX100 II camera. It also shoots full HD video with a wide-aperture Carl Zeiss lens and 3.6x optical zoom.
The QX10 is the cheaper of the two, packing a 18.2-megapixel Exmor R CMOS sensor with a 10x optical zoom Sony G-series lens.
The QX100 has a 20.2-megapixel Exmor R CMOS sensor, the same found in the critically acclaimed Cyber-shot RX100 II camera. It also shoots full HD video with a wide-aperture Carl Zeiss lens and 3.6x optical zoom.
The QX10 is the cheaper of the two, packing a 18.2-megapixel Exmor R CMOS sensor with a 10x optical zoom Sony G-series lens.
This is a serious camera and arguably a huge upgrade to any smartphone camera on the level of Nokia Lumia 1020 with its Pureview sensor. The QX10 has numerous exposure settings for those who like to tinker, and there's even a control ring around the lens that you can assign to various settings.
It's good to see finally that Sony is trying things out and being creative.
It's good to see finally that Sony is trying things out and being creative.
Isocell
ISOCELL is Samsung's new, advanced pixel technology for CMOS image sensors. As we know, the quality of the camera's image sensor is determined by the amount of light captured by the individual pixels within the sensor array. Isocell technology is the result of shrinking pixels to improve image quality without increasing camera size. To do so, Samsung built upon past techniques and formed a physical barrier between neighboring pixels - isolating individual pixels - which increases the amount of photons that can be collected and absorbed by the camera's sensors.
Samsung says this technique, which is patent pending, improves light capture and efficiency by 30 percent.
Interestingly, this sensor is specifically designed for 8-megapixel units, which could mean a drop down from the 13-megapixel camera's seen in the Galaxy S4 and Note 3. A full camera unit housing ISOCELL would also take up less space inside devices compared to previous imaging sensors, with a reduced height that sounds like it could be ideal for the company's future high-powered, even thinner smartphones. The first smartphones with this technology should be announced this year.
Samsung says this technique, which is patent pending, improves light capture and efficiency by 30 percent.
Interestingly, this sensor is specifically designed for 8-megapixel units, which could mean a drop down from the 13-megapixel camera's seen in the Galaxy S4 and Note 3. A full camera unit housing ISOCELL would also take up less space inside devices compared to previous imaging sensors, with a reduced height that sounds like it could be ideal for the company's future high-powered, even thinner smartphones. The first smartphones with this technology should be announced this year.