Let me start by saying that there is a time and a place for shooting in full auto.
If you're a beginner photographer, for example, full auto allows you to focus on things like composition, framing, and simply getting comfortable with your camera.
However, there comes a point in every photographer's life when full auto just doesn't cut it anymore.
In fact, when it comes to mastery of essential photography skills, eventually, full auto not only becomes a crutch to your further development but a hindrance as well.
Let me explain further...
Why Full Auto Doesn't Work
There are a myriad of reasons why full auto eventually becomes a hindrance to photographers...
The Camera Makes Decisions, Not You
At the very core of the issue is that shooting in full auto simply doesn't allow you to have the input you need to create the best photos.
Think about it - in full auto, your camera makes all the decisions for you. It's determining aperture, shutter speed, and ISO, among other things.
And though when you're a beginner that's very handy, once you get some time behind the lens, you need to start taking some of the control away from the camera.
No matter how fancy your camera and lens, it will never be as good as your eyes and your brain at seeing a scene for what it is.
Think about it like this: if you buy a sports car, having one with a manual transmission or paddle shifters allows you to improve the performance of the car by deciding when to change gears, how long to keep the car in that particular gear, and so forth.
The same holds true for your camera: taking manual control over things like aperture, shutter speed, and ISO allows you to improve the performance of your camera by deciding what to change and when.
Where's the Artistic Expression?
When shooting in auto mode, you can obviously still make decisions about things like composition.
However, with the camera in complete control of the settings, it minimizes your ability to get creative with the manner in which your artistic vision is expressed.
Let's say that you love landscapes and that you want to blur the motion of waves as they lap at the beach.
You set up your camera on a tripod, frame the shot, check the focus, and add a neutral density filter to your lens.
Then you press the shutter button in auto mode and...
No blur. There's nothing particularly wrong with the image above, but it certainly doesn't have the blurry waves we wanted...
In full auto mode, it doesn't matter what you do to set up the shot - in the end, whatever the camera thinks is the appropriate exposure is what will result, and that will not always jive with the creative vision you have in your head.
It Doesn't Challenge You
I'll be the first to say that when you're just starting out in photography, there's enough challenges that using full auto isn't all that bad of an idea.
But as I noted earlier, at some point, you will grasp all those non-camera-setting concepts and need to move beyond having your camera set to that little green full auto box.
Eventually, shooting in full auto will stunt your growth as a photographer.
Instead of learning how to manipulate exposure settings, you're conditioned to simply press the shutter button without much thought.
For example, let's say you're taking a portrait of a friend or family member like the one above, but when you shoot in full auto, the image is slightly underexposed and the background isn't as blurry as you'd like.
If you're shooting in full auto, what recourse do you have?
But if you're shooting in manual mode (or even a semi-automatic mode like aperture priority or program mode) you have plenty of options.
To correct the underexposure, you can open up the aperture by a stop. Using a wider aperture also helps to blur the background, since aperture and depth of field are intimately intertwined.
But if you never get out of full auto, you might not know that, let alone how to use those settings to get the results you want.
The Flash Rears Its Ugly Head
If the camera thinks the scene is too dark, it'll deploy the pop-up flash to try and get a better-exposed image.
The problem with this is that the pop-up flash not only emits terrible light, but unless the subject is within a few feet of you, it won't emit enough light to get a better exposure anyway.
What results is an image that's still too dark, but with the addition of ugly, harsh lighting with very bright (and likely washed out) highlights and very dark, defined shadows.
In other words, it's not a good situation.
Get a nice overview of the problems you can encounter when shooting in full auto mode in the video below by Bethany Kay:
Benefits of Shooting in Manual Mode
Just like there's quite a few detriments of shooting in full auto, there are quite a few advantages of shooting in full manual...
You Learn About Exposure
Where with full auto you simply press the shutter, in full manual (or even in the aforementioned semi-automatic shooting modes) you have to be active in the process of determining the exposure level in your photos.
And though exposure is a little difficult to grasp at first, the only way to figure out how aperture, shutter speed, and ISO work independently and together to get a well-exposed image is to actually force yourself to manipulate those settings. Manual mode is the way to do that.
Having an understanding of the exposure triangle will open up new worlds to you that you never thought possible.
From taking photos of your kids playing sports in poorly-lit gymnasiums to landscapes on your summer vacation to outdoor family portraits and everything in between, having an understanding of how to change the exposure settings yourself will allow you to photograph just about anything, anywhere, anytime with better results.
What's not to like about that?
You Become More Creative
By being in charge of aperture, shutter speed, and ISO, you have so many more opportunities to be creative with your photos.
Sure, mastery of these settings will help you understand exposure, but these settings also influence how your images look from a creative standpoint.
Use aperture to change the depth of field, from blurry bokeh in a shallow depth of field for portraits (like the one above) to a large depth of field for maximum sharpness in landscapes.
Use shutter speed to freeze the motion of moving subjects, or, like mentioned earlier, get nice motion blur to indicate movement.
Use ISO to allow you to manipulate the aperture or shutter speed even more, or simply use it to introduce digital noise for a gritty look.
What's more, manual mode allows you to venture into the world of long exposures. You can also master tricky lighting situations like creating silhouettes.
In other words, manual mode is a whole new world of creativity for your photography.
Check out these and other reasons for getting creative in manual mode in the video above by Simple Photo School.
There's More Consistency
I'll be the first to admit that at first, manual mode probably won't get you more consistent results. It takes some time to master.
However, eventually, you'll start to see that there's far less guesswork and much more consistency from shot to shot (especially regarding exposure) once you've got manual mode figured out.
Think about it like this: when in full auto, it's like you're rolling the dice - you have zero control over what the camera does, so you just press the shutter and hope for the best.
This can lead to wildly different results from one shot to the next, and certainly from one shooting situation to the next.
But in manual mode, you learn what settings are appropriate for what situations. And once you do that, you'll find that it's no longer a rolling the dice sort of situation, but that you get predictable results from shot to shot.
It's More Than Point and Shoot
If I haven't convinced you of the virtues of shooting in manual mode yet, consider this...
If all you do is shoot in full auto, all you really have is an expensive DSLR or mirrorless point and shoot camera.
Why pay all that extra money for added camera controls, interchangeable lenses, and so forth, if you don't take advantage of it?
If you do nothing but shoot in full auto all the time, you might as well save the money and buy a cheap compact camera because it will serve the same purpose when all is said and done.
Putting It All Together
I said it earlier, and I'll say it again - I'm not anti full auto mode for beginner photographers. There are some real benefits there when you're just starting out.
But if you have an appreciable amount of time behind the lens, get out of full auto - now!
The sooner you start to take control of what your camera does, the sooner you'll understand how to use those controls and the sooner you'll start to see more pleasing results.
Yes, it takes more time and effort to work in manual mode than it does in auto, but believe me when I say that the improved results you get in manual mode makes that time and effort more than worth it.
If you're scared to move out of full auto, take baby steps.
Here's a great introductory tutorial on shooting in manual mode by Tony and Chelsea Northrup to get you started: