Issues may have been early implementation and compatibility. ETTL and i-TTL are not that different from matrix metering, the sensor detects the pre-flash from the area onN the image that the camera focuses on, so it's not just measuring the flash, but where the flash is reflecting from. It also has ambient light measured, so it can chose full flash or mixed ambient, based on the whole image.
The loss of interest in supplemental lighting may have a lot to do with CMOS sensors, which have very good low light sensitivity. I don't use flash anywhere as much as I use to for low light work, I use it mostly to control lighting during a session. And with digital, you can view test shots immediately. None of my flashes are TTL compatible with my current digital equipment...
No, ...
- the 'dependability' is as one consideration...I could mount the camera on a tripod with eTTL flash mounted in the hot shoe, and in a series of 10 test shots, one or more would be overexposed, as if the connect between hot shoe and hot foot had wiggled and disturbed the command between camera to flaah commanding a certain level of partial power output.
- Secondly, where I could mount the flash in a softbox and get accurate flash output from TTL, if I mounted the flash in a softbox with eTTL, I would NOT get an accurate flash exposure. Yet, at the same time, if I took it out of the softbox and used ceiling bounce, the eTTL flash exposure WOULD be accurate in the exact ame setting! I could not use my desired lighting methodology.
- Lastly, if the on-camera eTTL exposiure was accurate, if I took the camera off the hotshoe and extended it on an eTTL extension cord -- and this happened with two different brands of Canon cord and two different brands of aftermarket cord during testing -- the on-extension eTTL flash would be intermittently wrong (at full power when it should have flashed at fractional power under eTTL command from the camera. I lost 'flexibility' of lighting solution, the ability to hold flash source higher overhead, or slighting off to the side so that the source position was improved to suit the circumstances.
Low light sensitivity has indeed made it so that one can get away without flash to make an exposure, so that is indeed the main reason for loss of interest. At the same time however, the quality of the lighting can leave a lot to be desired, because faces are shadowed (the source is not filling the area of the face seen by the lens), serious undershadows under the chin or eye sockets in shadows are captured (the overhead, dim lighting), or seriously colored/tinted (ambient lighting is mostly gelled) really need to be compensated with near-camera source. The need for supplemental lighting still existing, but folks are too forgiving of the
poor light quality captured by the highly sensitive sensors...the NEED is not eliminated!!!
Just a few days ago, I was at a ice skating area at night with extended family, as my wife and I were treating all to free skating session followed by hosted dinner, in lieu of buying them unwanted/unneeded Xmas gifts. The quality of light was miserable, although successful exposures could be made in the low light. And there were many shots that the light level was so low that a too-slow shutter speed (for the level of action of the skaters) blurred the resultant shot...flash would have remedied that! The NEED was not eliminated to freeze the action. Had been covering the event in a professional capacity, I would have selectively used flash to guarantee a satistisfactory exposure while capturing sufficient ambient light to preserve the inherent 'mood' of the place. But since I was effectively the typical snapshooter with no flash, there were blurred throwaway shots instead at those locations of very low light.