It is true that cell phones have come a very long way when it comes to their camera. In any decent cell phone today you don’t even get just one camera, you actually get two. The rear camera in the new Google Pixel 3 is 12.2MP which is fantastic for something so small. But the pixel size is only https://store.google.com/us/product/pixel_3_specs?hl=en-US . I’ll use this phone as a comparison to my Canon T6s and T5i.
If all you ever do with your camera is set it to Auto and press the shutter button then your smartphone, whatever it is, will do a fine job. If you believe that taking good photographs boils down to “he who has the best hardware wins,”(And perhaps a few Instagram filters) there is no hope for you. If however you are a person who is interested in the art of photography then consider the following.
Your camera is simply a tool that captures light. Like any tool there are good ones and there are bad ones. There are very specialized tools and then there are handyman tools. Like any other trade out there photography has professionals and those professionals need the best tools to help them perform their trade. Indeed, our livelihood depends on how well our gear performs. However just like any other trade there are also amateurs and enthusiasts, the do-it-yourselfers and handymen. Professionals spend years studying how to best use their tools and get the very best performance from them. If you think a professional photographer, and by that I mean one who earns an income from their trade would ever consider showing up for their job with a smartphone, then you are mistaken.
There are many reasons for not using a smartphone for client work. First off, the camera must always do it’s job when it needs to. A camera won’t take great photos, for that is the photographers job, and a good photographer could also get great photos on a cell phone. Rather the camera must be able to perform and “get the shot.” The camera must never lose focus and the operator must be able to rely on the camera to do exactly as his artistic vision and eye for aesthetic drives him to operate it. Ever had your phone lose focus while you were trying to catch a photo of your pet doing something funny? I have, and because of that alone I cannot rely on my phone in a situation where there is a need for a photo to be captured perfectly at the instant it needs to be.
In raw pixel power the Google Pixel 3 has 12.2MP. That’s a lot of resolution for a smartphone but that doesn’t impress me when you compare it to my Canon T5i which came out in 2013, a full 6 years earlier than this phone. My T5i has an 18.0MP sensor. With 6 million more pixels my old camera wins in the resolution department. But it gets more complicated. The Pixel 3 has a 1.4μm pixel size, my T5i has a pixel size of 4.3 µm. What this means is that I have a much larger sensor, not just one with higher resolution. The larger pixels mean that there is more surface area for light to enter the camera and be detected by those pixels. It also means that I have greater depth of field.
I’ll show you what I mean.
Of the above two photos both were shot at presumably 100 ISO. I wouldn't know if my phone actually shoots at that or just tells me it does. I have no idea what the zoom was on my phone to get this shot, but it was bad. If you like the photo taken with the DSLR over the smartphone, then you are now experiencing why a cell phone will never beat a DSLR.
As you can see above, this is how my smartphone viewed the scene from the same location as my DSLR. In fact I set my smartphone on my tripod head to get the location exact. I had that location because I wanted to use a 50mm lens to get strong depth of field effect to blur our the background. As you can see my background was very simple, just a sheet of paper draped over a shelf above a table. In order to "zoom" my cell phone had to crop the image. So a 12MP sensor loses a bunch of that resolution in order to zoom. But with my DSLR if I need more reach I can simply detach one lens and put a telephoto lens on. I still get to use all my pixels.
In order to convey that this is a toy I wanted to use shallow depth of field to show off the size of this HO railroad car. When I try to do the same with a smartphone the results are very hit and miss.
As you can see these two photos look totally different, however the only thing I changed was my aperture. Because my sensor is large I can get good depth of field. Now lets look at how a cell phone does at this with the tiny lenses and sensor.
Yuk! What is happening is twofold. I have no control over the depth of field. The pixelation isn't because of a bad camera, but rather because the camera can't handle the dynamic range of the image between the shadows and light. There are ways to give a smartphone camera depth of field, however those methods are not reliable enough for professionals.
Smartphones have a fixed aperture, and since aperture controls the depth of field in an image there is no way to fix this lack of creative control. The pixelation is caused more by the signal processor on the phone. Cameras have very powerful processors that chew up battery while they work to remove noise and artifacts from the sensor. Cell phones have to make sacrifices like crazy in that regard because they need to last all day away from home. DSLRs have removable batteries, and they can be changed in a few seconds.
Flash: Off camera flash makes a huge difference. One of the things that every good camera has is called a "hot shoe" which is used to mount a flash or otherwise a flash controller. This means that we can set flash units off remotely and wirelessly. We can set them in any orientation around our subject we want. We can also have very powerful flash units that contain their own battery packs. All smartphones will have an LED rather than an Xenon flash. These LEDs are not as bright as a flash and cannot trigger off camera flash units as slaves. This actually makes smartphones useless for many situations such as what I just demonstrated. Granted, you can work around these issues a bit. But why work around something when you can fix it with the right tools?
In conclusion: Smartphones have come a very long way and are amazing tools. If you get technical they should be trash when you consider the technical specs like sensor size and pixel density. Even the controls and optics should be bad. Manufacturers have done amazing things with them, but they have hard limitations. You can of course find professionals that take amazing photos with Iphones. Any camera in the hands of a photographer that has artistic skill can make something beautiful, however smartphones will always be gimped by their limitations. They will always be this way, they will always conform to the size, weight, cost, and heat compromises in order to meet the specs. Just because those phones are popular doesn't make them superior.
Lastly we can't forget that smartphone cameras have opened up photography like never before. We are experiencing the painful birth of a new imaging Renaissance. At no point was photography so accessible thanks to cell phones. At no point have we ever had the ability of every adult in the US to be a photojournalist, to catch news and interesting things as they unfold. But for us professionals, we will use our pro gear for work, and we will always take better photos thanks to the gear, and many new photographers will get started with a smartphone. And that's a great thing for the future of photography.