TTL vs Manual mode with flash?

When you are working with a off camera flash, when are you using the flash in manual vs TTL?

TTL here

Most of the time. My old Pocket Wizards don't do ETTL. I have an EOS ST-E2 unit which works in ETTL, but I find it sort of finicky (line of sight and such). I end up fiddling just as much or more, so it's often easier just to go manual from the beginning. Especially if my subject and flash aren't changing location.

E-TTL is most effectively used in situations where the distance between the subject and the speedlite changes constantly. For example, you are shooting pictures of players in a basketball game. Because the players are moving toward and away from your speedlite, the power level of your flash needs to change accordingly. E-TTL is a good choice, because it can do a quicker job than you could manually. This could be useful tool when shooting a wedding.

If your subject is static, then setting the flash exposure manually is fine. You have plenty of time to change the power setting.

It is important to clarify what we are talking about here is using manual or automatic FLASH exposure. E-TTL is letting the camera set the flash power level automatically. Using manual exposure involves the user setting the power level on the back of the flash unit.

lucky1one wrote: E-TTL is most effectively used in situations where the distance between the subject and the speedlite changes constantly. For example, you are shooting pictures of players in a basketball game. Because the players are moving toward and away from your speedlite, the the power level of your flash needs to change accordingly. E-TTL is a good choice, because it can do a quicker job than you could manually. This could be useful tool when shooting a wedding.

If your subject is static, then setting the flash exposure manually is fine. You have plenty of time to change the power setting.

First off, thank you all for your answers.

Now considering what you have said, even with a static subject what reason would there be to shoot in manual flash? If E-TTL does all the leg work, static or not, why would you use manual flash?

Manual == consistency. Once the aperture is set, it doesn't change.

As lucky pointed out, TTL compensates for distance AND aperture changes.

Matthew

Casey T wrote: Now considering what you have said, even with a static subject what reason would there be to shoot in manual flash? If E-TTL does all the leg work, static or not, why would you use manual flash?

The ETTL is run by a reflective light meter, which is easily fooled by changes in tone even if the light does not change. For instance when I switch from a bride in all white to a groom in mostly black. If I've set the flash power manually it'll keep giving me the same exposure, so I can just keep shooting. If I'm using ETTL I have to take some test shots to figure out how much lighter or darker to tell the camera to compensate for.

Any time you let the camera choose the settings, you are trading control for efficiency. The camera does not know what you are shooting or what your visual intent is.

There are situations when you want to switch to manual:

a. your subject may blink at the preflash when you use TTL. As a result, the subject's eyes are closed when you fire off the shutter. One way to get around this is to manually fire off the preflash by pushing the FEL button and let the person blink first. Then you fire off the shutter after a brief moment.

b. another potential problem could occur when you try to trigger non-Canon flashes with optical slaves. These non-Canon flashes may be fooled by the preflash and trigger prematurely. This is the reason you need to switch to manual.

c. when you set your camera to aperture priority and TTL mode, your camera automatically sets the shutter speed. What happens when you shoot in low light conditions is that the camera will often set an excessively long shutter speed. As a result, the background (ambient light) is overexposed. If you want greater control of the ambient light exposure, then you need to switch to manual.

lucky1one wrote: c. when you set your camera to aperture priority and TTL mode, your camera automatically sets the shutter speed. What happens when you shoot in low light conditions is that the camera will often set an excessively high shutter speed. As a result, the background (ambient light) is overexposed. If you want greater control of the ambient light exposure, then you need to switch to manual.

I think you mean low. A high shutter speed would underexpose the ambient light.

yes, you're right. I mean excessively LONG shutter speed. Thanks for the correction, HP.

lucky1one wrote: yes, you're right. I mean excessively LONG shutter speed. Thanks for the correction, HP.

I do the same thing all the time. My brain knows what I mean, but my fingers type it backwards.

Henry Peach wrote:

lucky1one wrote: yes, you're right. I mean excessively LONG shutter speed. Thanks for the correction, HP.

I do the same thing all the time. My brain knows what I mean, but my fingers type it backwards.

Happens to me too!