What’s With All The Megapixels!?! (Updated)

Do I Really Need a 50 Megapixel Camera?

High-end cameras are offering sensors with more and more resolution (i.e., high pixel-counts). This month, Canon will ship its two new ultra hi-resolution cameras, the EOS 5DS and EOS 5DS R, each with 50.6 megapixel full-frame sensors! This raises the question: just how important is sensor resolution, and, is more megapixels really better?

Well, the answer is not straightforward. So, I’ll try to simplify.

First, take a look at this ultra-high-resolution image of the Andromeda Galaxy. It’s a 1.5 gigapixel image. That’s 1,500 megapixels! With this ultra-high resolution, we can progressively zoom in on any part of the image and reveal details that a lower resolution image could not contain.

While this image is a composite of thousands of images, you should be able to immediately see how ultra-high resolution like this lets you explore an image, rather than just view it. I think that this is the future of photography. Imagine taking a camera with resolution of 100 megapixels or more on your next vacation to Paris. When you return, not only do you show your vacation photos to your friends, but actually explore them. Instead of yet another boring picture of the Eiffel Tower you have an image packed with detail. You zoom in to see if that couple on the tower was holding hands or arguing. You pan and zoom the image to see what was going on at that moment in the smallest detail. Perhaps, you can even zoom in to see the individual rivets on the Tower and study how it was constructed.

Oh, BTW, this has actually been done. Here’s a 26 gigapixel image of Paris! And, just this week, the world’s largest picture was published. It’s a 365 gigapixel panoramic shot of Europe’s Mont Blanc, made from 70,000 individual hi-resolution images.

I believe, sensors with resolution like this are coming to prosumer/professional cameras over the next few years and will become increasingly affordable.

This capability will add a whole new dimension to still photography.

Some other benefits of high pixel-count cameras include:

  • Increases the information value of an image.
  • Let you get more out your expensive glass. After all, generally speaking, your lens is capable of capturing more fine detail than your camera’s sensor.
  • Let’s you blow up a photo dramatically and print really large with excellent quality.
  • And, while not a substitute for good composition, high resolution makes it possible to greatly crop an image without sacrificing quality.

OK, What Are the Drawbacks?

Yet, there can be downsides to all that resolution. Obviously, price is one. But, the rule of technology vs price is that price invariably comes down even as technology improves (as exemplified by Moore’s Law). As manufacturers pack more and more pixels onto their sensors, noise becomes an ever-increasing issue. That’s because the pixels are much smaller, and, smaller pixel elements tend to have a lower signal-to-noise ratio (SNR). There’s a limit to the SNR of today’s sensor CMOS technology. I’m convinced that advanced sensor and image processing chip technology will address this. For example, Fuji has developed an Organic CMOS sensor technology with dramatically-improved SNR (plus greater dynamic range!). Other technologies will almost certainly come to market offering extremely small pixel sizes with excellent SNR.

Other negatives are the time it takes to download/upload ultra-high resolution images and their storage requirements. These images can be hundreds of megabytes or even gigabytes in size. As newer interfaces such as USB 3.1, Thunderbolt 2 and high-bandwidth WiFi become ubiquitous, I don’t think the time it will take to download an ultra-high resolution image from your camera to your computer will be any longer than that 22 megapixel image is today. And, with local disk storage (as well as cloud) getting cheaper, I don’t think file size is really going to be a significant factor in the near future.


So, will I buy that new 50.6 megapixel Canon? Probably not. I’ll stick with my EOS 5D Mark III with its 22.3 megapixel sensor and hold out for a 100+ megapixel model!