For instance, the original Samsung Focus took some lovely shots on its 5-megapixel camera, while the Motorola Droid Razr 's 8-megapixel lens creates disappointing pictures. And the 5-megapixel camera on Apple's iPhone 4 beat out some 8-megapixel cameras on the market and delivered good low-light results. Of course, that's not to say that bigger can't also be sometimes better. For instance, HTC's One X high-performance 8-megapixel smartphone camera boasts rapid shot-to-shot action, and its Titan II takes megapixel shots of solid quality.
So what's the formula for fantastic photos? It involves an entire camera module that includes not just the size and material of the main camera lens, but also the light sensor behind it, the image processor, and the software that ties it all together.
Note : As always with this column, if you already consider yourself an expert, then this article is probably not for you. Key ingredient 1: Sensor Most budding and professional photographers will tell you that the most important ingredient in the optical system is the sensor, because that's that's the part that captures the light. The sensor is essentially the "film" material of a digital camera. No light, no photo. 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.
The size of the image sensor is important, and generally, 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 the image. The experts I spoke to for this story had colorful ways of describing the relationship between pixels and sensors, but "buckets of water" or "wells" were a favorite intentionally oversimplified analogy.
Imagine you have buckets pixels on a blacktop sensor. You want to collect the most water in those buckets as possible. To extend the water-and-bucket analogy, the larger the sensor blacktop you have, the larger the pixels buckets you can put onto it, and the more water light you can collect.
Larger sensors are the reason that 8 megapixels from a digital SLR camera are better than 10 megapixels from a smartphone camera. You have the same number of pixels, but those pixels on the DSLR can be larger, and therefore let in more light. More light generally equals less-noisy images and greater dynamic range.
The fallacy of megapixels You can start to see that cramming more pixels onto a sensor may not be the best way to increase pixel resolution. Jon Erensen, a Gartner analyst who has covered camera sensors, remembers when the cell phone industry jumped from 1-megapixel to 2-megapixel sensors. You want to collect the most water light in those buckets as possible. To extend the water-and-bucket analogy, the larger the sensor you have blacktop , the larger the pixels buckets you can put onto it, and the more light water you can collect.
Larger sensors are the reason that 8 megapixels from a digital SLR camera or 5 or 13 best those 8 megapixels from a smartphone camera.
You get roughly the same number of pixels, but the pixels on the dSLR get to be larger, and therefore let in more light. More light generally equals less-noisy images and greater dynamic range.
You can start to see that cramming more pixels onto a sensor may not be the best way to increase pixel resolution. That hasn't stopped the cell phone industry from doing just that. Jon Erensen, a Gartner analyst who has covered camera sensors, remembers when we collectively made the leap from 1-megapixel to 2-megapixel shooters. 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, increased resolution wasn't worth very much. Noise increased," he said. The relationship between the number of pixels and the physical size of the sensor is why some 8-megapixel cameras can outperform some , , or even megapixel smartphone cameras. There's more involved, too. A slim smartphone limits the sensor size for one, and 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.
Then again, drastically shrunken pixel sizes aren't always the result when you increase your megapixels. As a result, the photo quality on both these HTC smartphones should be comparable at a pixel-by-pixel level. Unfortunately, most smartphone makers don't share granular detail about their camera components and sensor size, so until we test them, the quality is largely up in the air.
Even if smartphone makers did release the details, I'm not sure how scrutable those specs would be to the majority of smartphone shoppers. For more information on the interplay between megapixels and sensors, check out the excellent description in CNET's digital camera buying guide.
The story behind the PureView smartphone as Nokia tells it is really interesting. I strongly suggest you read it. Alakarhu explained to me that although Nokia has engineered the to capture up to 41 megapixels, most users will view photos as the 5-megapixel default.
Usually, when you use the digital zoom on your phone, you're blowing up and cropping an image to see each pixel up close. While CCD sensors used to be the most commonly used type of sensor, technological advancements combined with the lower manufacturing costs of CMOS sensors has changed this. However, over the years these differences have become a lot less marked.
Although the type of sensor has less of an impact on image quality than it used to, sensor size or format is something that does have a significant impact. The three most common camera formats are APS-C or crop-sensor , full-frame or 35mm , and medium-format. Crop-sensor cameras are the smallest of the common sensor sizes, measuring approximately Their smaller size, lighter weight and lower price tag make them most popular with those just starting photography and they are commonly used in both entry-level and mid-level cameras.
The most common film formats were 35mm, medium-format and large-format. Crop-sensor cameras only really came out of necessity for a cheaper alternative to 35mm sensors. As technology continues to progress and the prices of sensors reduce, we may even see the disappearance of these smaller sensors. Full-frame cameras are slightly larger than crop-sensor cameras, with sensor sizes of about 36mm x 24mm.
Larger and heavier than crop-sensor cameras, they offer better image quality, perform better in low light conditions, and allow for greater depth of field control, but at a slightly higher price. The introduction of mirrorless cameras has also changed the game when it comes to size variations between crop-sensor and full-frame cameras. Because they do not have a mirror-system, mirrorless 35mm cameras are now basically the same physical body size as crop-sensor DSLR cameras.
This means you can have a higher quality image, but in a smaller, more light-weight camera body. Finally, medium-format cameras, with sensors of about However, this quality does come at a much higher price, which means they are often only used by professional photographers or those looking for the highest quality.
So why does the sensor size have an impact on image quality? To understand this, we need to understand how images are formed. In this course, you will learn the 6 essentials that will get you confidently shooting creative images in manual mode. Sensors are what allow digital cameras to record images. Made up of millions of photosites which are what record the information contained in individual pixels , sensors record an image when the shutter button is pressed.
This exposes the photosites to the incoming light that is then recorded as an electrical signal on the sensor. The strength of each of these signals is converted to digital values that essentially produce the image once the exposure has ended. Each photosite, due to a filter placed over the top, is only able to capture one of three primary colours red, green or blue.
The most common of these filter systems is called a Bayer array. This array, invented in by Bruce Bayer, consists of alternating rows of red-green and green-blue filters.
As each photosite is only able to record one colour, certain colour data is lost when initially capturing the image, so a process called demosaicing is required to convert the array of primary colours into the final photo. This is done using certain mathematical algorithms, and it is these algorithms that result in the different colour representation of the various camera brands and is ultimately what dictates why a Hasselblad colour rendition may be different from Phase One, for example.
In addition to Bayer Array filter systems, Fuji created a different, more random array called an X-Trans sensor. But I hasten to say that the improvement is more the result of me being a better photographer now than I was 15 years ago, rather than just an upgraded sensor. Long story short, great camera, but perhaps not the best fit for my shooting style.
It produces amazing image files, but with a tendency to frustrate the heck out of me along the way. Without question, I can do everything with it that I can do with my D But, in practice, it takes a lot longer to do the same things, and the process of doing them is a lot less fluid. Ironically, 15 years in, that effort started back at the beginning.
Certain shortcomings of the GFX highlighted certain gaps in my technical knowledge that I never had to address before. So, I had to do an extended amount of research to strengthen those muscles just to be able to use the GFX properly. Yet, a funny thing happened. Rather than my newfound technical knowledge causing me to fall in love with the GFX , I instead found myself applying those newfound skills to my trusty old Nikon.
Suddenly, a camera that I was giving serious consideration to leaving behind was again staking its claim as my favorite camera. Without a doubt, shot in a vacuum, the sheer image quality of the GFX was still a cut above the rest.
But, by applying those new skills that had been forced upon me by the new system back into my old system, I was realizing that my existing lower-megapixel camera was perfectly capable of producing files that looked just as good.
Some benefits that I had been ascribing to high megapixels were really just a matter of technique. Even more unexpected, after a decade and a half of asking how I could get more megapixels, I instead found myself looking for every opportunity to use less. And I was doing so with a camera body that I personally found more efficient and enjoyable to use. I suddenly found myself in a position where my most expensive and impressive camera in terms of specs was the one I least enjoyed using.
And while, if one were to put the files from all three cameras side by side, there would be a definite difference in quality when pixel-peeping, when I stepped back and tried to just judge the artistic merit of the various images I was creating, I found I was still creating better work with the Nikons. Of course, this is purely subjective and impossible to quantify. That could simply be a result of having so many years of experience holding them.
Again, completely subjective, and not an official review that should sway your opinion one way or another. But, for me, the differences felt real and were having an actual effect on my ability to achieve results I was happy with. I wanted to dig deeper and see if I could apply some more objective logic to which camera I was using and when, so I could make better investment decisions in the future.
Like every good education, there was a lot of math involved. I am an advertising photographer by trade. So, my choice of camera is not based solely on my personal enjoyment. My clients need image files that can be cropped multiple ways, blown up large from all the various crops, be viewed up close, and still retain their sharpness.
So, there is a practical reason why I tend to invest in higher-megapixel cameras and medium format systems. In fact, part of almost every bid I submit for major ad campaigns is a line item for rental of a medium format system. Generally this is the Hasselblad or Phase One system.
The purchase of the GFX , in fact, was partly driven by a desire to retain some of that rental income myself by renting the system to my own productions. While delving deep into my re-education, I decided to do a bit of research to find out exactly how many megapixels were required to make various sizes of prints.
This led me to various online calculators that allowed me to put in the megapixels associated with each of my cameras and find out what the largest print was that I could make from that camera using dpi as a baseline. Of course, you can lower your dpi to make larger prints, but I wanted to base my analysis on the highest quality possible.
What I found was this: A MP image in the 4x3 aspect ratio of a medium format sensor could print natively at dpi an image of My And my That, of course, assumes no cropping is involved. So clearly, as expected, the more megapixels you have, the larger you can print before you have to start decreasing the dpi.
That is what you are paying for when you opt for a high-megapixel camera. And that is why one might want to invest in a camera with more megapixels if they have clients who require their images to be printed large.
Or, as is often overlooked in the discussion, if one has clients who want to crop heavily into that image and still be able to print large. Like I said, the majority of my income is derived through commercial photography aimed at advertisers. A large percentage of it will also end up in the digital world, in the editorial world in a magazine, in a print for a fine art exhibition, or simply printed for my portfolio. So, I wanted to go back through my work over the last several years and do an analysis of where the vast majority of my images actually did end up being printed, if they were being printed at all.
And how did that jive with the amount of money I had invested in increased megapixels? What I found was that for the bulk of jobs that did require higher-megapixel counts to suit advertisers needs, I was renting medium format Hasselblads or Phase One cameras with higher megapixel counts. They just feel more stable when big money is on the line to me personally. And because the type of clients that actually need that level of quality usually accept the fact that they will have to pay for it, it is a financially neutral situation from a business standpoint.
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