Many folks don’t know the difference between TTL vs manual flash, or how it will change the way they create.
Most photographers realize that flash output is still better than constant lighting. But the biggest struggle is with TTL vs. manual flash output. Most people don’t understand it. And to be honest, most experienced photographers are also frustrated with it. But in time, you learn to tell it what to do. Think about it this way. You use your camera in manual mode, right? And if you don’t, then you at least know how to do so. The strobe and flash output that you can get is similar.
It’s About Communication with TTL vs Manual Mode
One of the biggest things about Off-Camera artificial lighting is communication. We live in a world of automation. But the truth is that all of these products cannot think for the most part. They can only do a job that they’re programmed to do. So if you tell a microwave to heat up your food for 30 seconds, it will only do that because it’s pre-set to do that. If you pressed the button for 3 and got a 7 instead, then there would be a communication problem. This means that you have to find a way to tell the flash to do precisely what you want it to do.
In the most rudimentary terms, TTL means through the lens communication. And most of the time, it’s incredibly finicky. The most basic thing that it’s supposed to read is your lens’s aperture and the ISO setting. First, make sure that your camera can read those things. Next, make sure that the flash is getting those communicated to it. If you’re set to ISO 400 and f2.8, the TTL flash will output enough light to correctly meter for that scene based on its own interpretations. Those interpretations are given to it by the engineers. It’s not considering that you’re bouncing it off of a wall, putting it in a softbox, etc. But it’s also looking at your focal length unless you set that manually. With that said, the same exposure can look different from one camera system to another when using the same flash. In a bind, it’s great to use. If you’re shooting a wedding or doing photojournalistic work, it’s usually a lifesaver. But you’re also using it with a hot shoe flash. It’s really perplexing with studio strobes.
“TTL communication requires specific pins on the camera hot shoe and flash to communicate and relay information about the exposure to make the two work together.”A quote from Useful Photography Tip #124: TTL vs Manual Flash: When Should You Use One Over the Other?
Most experienced photographers really prefer to use manual flash. Think about it this way. When you shoot photos, you’re probably shooting in manual mode. When you shoot pictures with a flash, we’re pretty positive that you’ll shoot in manual mode too. You’re telling the camera exactly, specifically what to do. You should do the same with a light. So you need to learn a whole different exposure style. Depending on your flash or strobe’s power output, the power output will vary. That’s to say that 1/4 power won’t be the same from a Godox hot shoe flash as it will with a Profoto strobe. But with manual setttings, you can figure it out and tell the strobe exactly what you want. Then it will do just that over and over again. That’s all photographers want!
Generally speaking, lots of photographers don’t experience the same performance in TTL vs manual. Some flashes will deliver different output based on the remaining battery life. But lots of more experienced photographers will work with TTL and hate it. That’s because the complicated camera metering system is giving them a result that they don’t want. Even though it’s supposed to deliver output based on the aperture and ISO, each camera system has a complicated metering system beyond that. Even the old tried and true Sunny 16 output isn’t always the same.