We’ve talked about controlling exposure before. There are three central parts to getting the light just right; shutter speed, aperture and ISO. Manual mode puts all three under your control.
That might sound intimidating, but it doesn’t have to be. Odds are, if you’re using a DSLR, you are already selecting one or two of these – the camera takes care of the last option, adjusting it to what it thinks is the right exposure.
So why does manual mode exist, if the other options are so much easier?
On any other mode, your camera makes a guess as to how bright the image should be. Often, that guess is very good; however, if you’ve ever tried to take a picture where the part you wanted bright was dark, or vice versa, you know that not even the most expensive model can read your mind.
It makes its guess by looking at the scene through the lens and taking an average of the brightness, factoring in the settings you have chosen. Behind the scenes, it then calculates where to set the remaining variable to put that brightness to a particular value that is usually just right.
Many cameras use tricks to improve these guesses, such as assuming the middle of the photograph is more ‘important’ than the edges. Mirrorless cameras, or DSLRs using Live View, might also look for things like faces, which are then given priority.
Unfortunately, your camera doesn’t understand what it’s looking at, which can lead to problems. Nighttime landscape photographs have a lot of darkness in them, and that’s what the eye expects. The camera will try its hardest, but still take a bland picture.
Not the exposure that you wanted.
Another pitfall of automatic exposure is situations that change. Imagine setting up to photograph an event and taking a test shot. After a few adjustments, you have the image you want. Now all that’s left is to wait. Finally, you take your shot – and it’s no good.
If anything changes in front of the lens, the camera has to make another guess. Imagine missing that shot of the finish line because a dark car parked off to the side after you took your test shot, even though the overall light didn’t change. Sounds frustrating, doesn’t it?
If manual mode is enabled, no setting changes without your approval – because nothing changes unless you change it. In a lot of situations, this isn’t just an advantage, but a necessary decision.
Some doors remain closed unless you take the controls yourself.
There is no better example than long exposure photography: past a certain point, your camera can’t work out what to do. For extremely long exposures, you have to make the call.
And it’s not just long exposure – many of the more creatives styles of photography really need manual mode enabled to pull off. Imagine a panorama with sudden changes in brightness, or a time-lapse video which won’t stop flickering. Cameras are set up to take ‘normal’ pictures, not to fine-tune a piece of art. That still takes a person.
Learning to set exposure for yourself doesn’t take very long (you can always try again), and opens up a whole world of imagination.
When Life is Simply Too Fast
Manual mode gives you the most control and, when you have time to use it properly, the best image. There are times, however, when it is simply too slow.
When the situation starts changing, there is some help. With manual mode enabled, a little bar in the viewfinder (or on the screen) helps you see where your exposure is relative to the camera’s ideal. Keeping an eye on that can help you get the drop on a sudden lighting change – but any adjustment has to wait until you have to physically move a wheel.
For high octane sports, or capturing that perfect, magical instant in nature, that can cost you the shot.
There are times when it is best to trust the camera. It might not get it right, but at least it has time to try.
Manual mode isn’t something you need to use all the time – though many people do. It takes a bit of practice, but the feedback is immediate and it doesn’t take long to get comfortable with it.
Modern cameras do a phenomenal job in getting exposure just right, and most of the time, you can always take another shot.
Just remember, fixing a tricky lighting situations is never more than a dial-click away.