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This post was most recently updated on January 8th, 2023

One of those never-ending discussions in photography. Whether to stick to manual or TTL. Here we will explain why TTL flash is necessary.

What’s The Difference Between Manual Flash And TTL Flash?

Manual flash is consistent. Once you have set your flash power, this will remain the same for every exposure. One persistent issue is that while the flash is consistent, the light can change. Take a sunset shoot for example.

The manual flash may be great in the early evening yet in darkness you may want to alter the exposure and have to change the flash settings manually.

Through The Lens metering, also known as TTL flash, is quick. It’s also automatic. As you focus your camera, during a half push of the shutter the camera is taking a reading of the scene. This is known as metering and is where the camera is measuring the amount of ambient light ‘Through The Lens’ to the sensor.

Just before the shutter is opened there is a short burst of flash before the actual flash. This short flash tells the camera how much flash is required for a good exposure and a well-balanced shot.

Cleverly, the power of the flash has been set by the camera itself, unlike a manual flash where you have to adjust the settings. Et voila.

When Would You Use A TTL Flash?

There is a short answer to whether TTL flash is necessary. Yes, of course it is, but it depends on the situation. Where a manual flash can feel regimented, a TTL flash can be flexible. TTL flash also works on whatever camera mode you are using.

Whether that be priority for the aperture or the shutter, scene mode, or automatic. If the subject has moved, the TTL flash can recognize that and react.

Take a wedding, for instance, you may use a manual flash for the comfortable early evening shots of the happy couple. In this situation, you have a good idea of how much power your flash will need. You can also set the subject for how you want them to pose.

However, for a dance at a wedding reception, you may prefer a TTL flash to automatically know how much flash is required for each shot. You can also get closer to the action if you are confident that the flash can react well to a shifting distance between you and the subject.

If you were bouncing the flash from a ceiling or wall, TTL flash would change automatically for the exposure.

The Drawback Of Using A TTL Flash

Unfortunately, while TTL flash is flexible and reactive it can be disappointing. Especially with a subject that can throw off the flash if they are wearing something significantly bright or dark. You can also get dull, flat images and a background that is underexposed.

The lack of concern for the background can be a major drawback if that remains a feature you want to capture. While the subject may be exposed well and evenly, the background can appear lackluster.

A lot of photographers simply want control and the TTL flash takes that away. It can also be an expensive feature to have with inconsistent results.

When It Is Necessary To Use Both TTL And Manual Flash

A TTL flash is necessary purely to give yourself the option in certain situations. On some flashes, you could use the TTL flash for getting close to the right exposure. It may not be perfect yet it works. Quickly switch to manual flash and it will use the same power output.

Essentially, the TTL flash has worked out what flash settings work allowing you to lock them in with the manual flash. Even if it needs some slight alteration, that is easily done with a manual flash. This trick alone can save a lot of time and is one reason why the TTL flash is necessary.

For novice photographers, knowing that the TTL flash will take care of getting a good exposure means you only have to work out how to make it great. This also gives you a better understanding of your camera and which settings you like.

Why A TTL Flash Is Necessary

Why A TTL Flash Is Necessary

For sheer ease-of-use, having a TTL flash means not fiddling with your Speedlite. Exposure is one crucial element to your shots. Having a TTL flash means that is one less thing to worry about when you want to be concentrating on taking pictures.

In event photography, you want to focus on your subject in the moment. If you want to save yourself the worry of the right exposure then opt for a TTL flash. It’s a great option to use for a changing situation, which a lot of events are.

When Would You Use A Manual Flash?

Manual flash is ideal if you know the situation you are shooting and can control it. Knowing the time of day and where the light will be is one thing. You also need to set your manual flash to your camera settings and the position of the subject you are shooting.

Having that peace of mind that the manual flash is set just how you want it is comforting. It will also result in a consistent exposure for your subject.

This is ideal for portraits where there is more control. You can dictate the pose of your subject and the position of the light to your exacting standards. For a static scene where you want to capture the moment just as you want it, go for a manual flash.

The Drawbacks Of A Manual Flash

The manual flash could be set to exactly what you perceived the situation would require. But things change. There is an art to estimating how much manual flash is required and that can be learned over time.

On the day of the shoot, you may find that after a test shot you need to tweak the manual flash. This may take longer than you want and you may find yourself doing this several times. A change in the weather or the light would require a change in the manual flash.

There could also be a change in the distance between you and the subject. If you need to take even a few steps back or forward, this can greatly alter the exposure which is where a manual flash can struggle. Using manual flash also means restricting yourself to using the camera only in manual mode.

Final Thoughts

Is TTL flash necessary? Yes, absolutely. You could be confident in relying on manual flash yet TTL flash does a lot of the work in getting the right exposure.

Manual flash is ideal for closed, controlled situations, TTL flash can save you time and stress during a lively event. By working out what settings make for a good exposure takes out a lot of guesswork.

This is not a competition between TTL and manual flash but finding out what works for you is merited. Both flashes are simply ways of getting the right exposure in various situations. As a classic tool, manual flash works in every single situation.

Reliable and dependable, you can set it how you want and it will deliver just that. TTL is reactive, it works in the moment and changes with the situation you are shooting so you don’t have to change the settings. With the flash working for you, you can simply concentrate on being in the moment capturing great shots.