ETTL- I'm dense. Explanations requested.

Ok - I give up. Need some help here. LOL. I can use studio strobes and speedlights in manual mode and the camera in manual mode and get the exact results I want. I use my speedlights in ETTL and it's a total crapshoot if it is exposed properly.

I shoot in manual mode so I can expose my background the way I want. Metering is set to evaluative. Consistently the photo comes out underexposed. I can start to get the results I want by upping the FEC to +1.5 or even 2.0. I have tried no diffuser on the speedlight, so I am not losing any stops that way. Very frustrating. I usually say "f-it" and switch over to manual everything, which is fine as long as my subject isn't moving.

Am I just not understanding ETTL correctly? I assume that:
1. No matter where I set my camera in manual mode, the ETTL will fire the flash appropriately to bring the object I am focused on to the correct exposure.
2. If I am bouncing my flash off of a card, ceiling, or wall, it will automatically increase power to ensure my subject is properly exposed.
3. If I want to over or underexpose my subject, then I can change my FEC to where it needs to be.

Are my assumptions even close? Gah. Any advice is appreciated.

THanks
James

It all depends on how much of the scene is highlight and how much is shadow. I tend to place the center AF point over what I want to be exposed properly, then FEL. compensation needs to be dialed in if there is a lot of light tones or dark tones.

You seem to understand the process. I think ETTL gets a bit of a bad rep in the sense that experienced shooters would never rely blindly on the reflected metering of their camera because they understand that the meter doesnt know whether its pointed at a white, gray, or black subject. But they expect that the automated flash system wouldnt be fooled by the same problems. Try the average setting rather than evaluative to see if that helps in the environments that you shoot in.

gonzogolf wrote in post #14057674
Try the average setting rather than evaluative to see if that helps in the environments that you shoot in.

Id try this. When I was using evaluative indoors to bounce flash, I couldnt get proper exposure, even at +2. When I switched to average, +2 creates a totally blown out scene.

Evaluative vs. Average:

http://neilvn.com …sh-average-vs-evaluative/

A more technical explanation:

http://super.nova.org/​DPR/Canon/TTL/

Excellent - I'll try setting it to average and see what I get. Thanks!

James

A few samples with EXIF would yield a more enlightening discussion.

gonzogolf wrote in post #14057674
You seem to understand the process. I think ETTL gets a bit of a bad rep in the sense that experienced shooters would never rely blindly on the reflected metering of their camera because they understand that the meter doesnt know whether its pointed at a white, gray, or black subject. But they expect that the automated flash system wouldnt be fooled by the same problems. Try the average setting rather than evaluative to see if that helps in the environments that you shoot in.

In my case, ETTL gets a bad rap for the following reasons (none of which are related to subject and background brightness):

• ETTL suffers from inconsistent communication between camera and flash, causing the flash to fire at full power randomly
  
• ETTL does not handle well the use of a softbox as flash modifier, either when flash head is pointed straight ahead or if elevated a few degrees
  
• Some ETTL cameras are known to have suffered from the need for semipermanently needing to dial in FEC +1 in order to get a properly illuminated flash exposure