Hi all,
this is my first post on this amazing forum. I've been having a look around for an answer to my question, both on this board and on others and haven't found out what I'm looking for.
I need a flashgun for some wedding / portrait photography. But I admit, I am an absolute novice when it comes to flash photography. I am using a Canon 550d, but looking at upgrading to a 5d or similar later in the year.
Trouble is, i have absolutely no idea what I need. I have look at a few models and frankly, the specs confuse me. Can anyone advise what the E-TTL II/ E-TTL/TTL, FE lock, High-speed sync etc actually means?
My budget for a flash gun is £0 - £250. Which is the "best" for that amount of money - in terms of reliability, manual control and ease of use. Ideally, i would like the flashgun to have wireless capability so I can set it on a tripod in the future. What other equipment would I need to do this.
ETTL is how the flash meters for exposure. The same thing as how your camera meters for exposure. Back in the times where dinosaurs roamed the earth, you had to manually calculate how much power your flash needed to expose your subject correctly depending on ambient light and also how your camera will be exposing the background (aperture has a direct effect on flash).
Times moved on and when cavemen became the dominant species, flash guns had their own built in metering sensor, so they could do some of the work to determining the correct output. However this was cumbersome and due to the camera and flash metering separately could sometimes provide inconsistent results.
Nowadays thanks to the wonders of modern technology the flash can do its own metering, fully automated, with the help of the camera. This is called
Through The Lens metering as just like the name suggests, it is done through the lens rather than a metering sensor on the flash (although the 580EX II still has its own metering sensor and you can use it if you want, although in 99% of cases TTL is the way to go).
Canon's version of through-the-lens metering is called
ETTL. It stands for
Evaluative Through The Lens. Conversely Nikon's version is called iTTL (the 'i' standing for Intelligent).
ETTL II is just an evolution of the original ETTL system which brings many improvements, none of which you need to worry about since pretty much every Canon EOS digital body and flash gun right now is ETTL II capable.
FE lock is
Flash Exposure lock. It's the same as AE lock (Auto Exposure lock) on the camera except it is just for the flash. If you have never used the AE lock button (it is the one with the asterisk, next to the AF point selection button) then it's helpful in certain modes like P, Av, Tv where you want to meter for one area but focus on another. You compose the shot, press the AE lock button and the camera locks the metering, which then allows you to recompose, autofocus and take the shot without the exposure settings changing.
This is helpful for example if you want to shoot a subject against a bright background and you want to expose the background correctly instead of the subject. You aim at the bright background, hit AE lock, aim at the subject, autofocus, shoot. In normal behaviour the camera would attempt to meter around the active AF point (for most people this would be the centre one) and you would not get the results you desired.
FE lock just allows you to meter the flash and then lock its exposure value then aim somewhere else and take the shot. Since the flash metering is also weighted to the active focus point, if your subject is wearing very bright or very dark clothing, when you go to take the shot and the flash fires its metering pre-flash, it may believe that it will underexpose or overexpose the subject unless it fires more or less (respectively) power than it needs. Doing nightclub photography I experience this often.
With FE lock you simply aim the center AF point at something which isn't very dark or very bright (for example the subjects face), press the FE lock button (which is the AE lock button when you have a flash connected), then recompose, focus and take the shot. If you have a lively subject/subjects then it's best to warn them beforehand that there will be multiple flashes and not to move until you tell them you're finished. FE lock does not affect the cameras exposure, although you should probably be shooting in M mode when using flash anyway.
High-speed sync (HSS) is a mode which allows you to use the flash with shutter speeds faster than the camera's normal X-sync speed. The X-sync speed is a hard coded value in the camera where it is determined that the shutter is fully open at any given moment. At higher shutter speeds, the shutter will have already started to close before it is fully open, which leads to problems with flash as only part of the image will 'see' the flash and you'll end up with some very odd results.
If you wish to use flash with faster shutter speeds then you need HSS. This is a mode on the flash which, instead of firing one powerful burst of light, fires multiple, lower powered bursts of light in very fast succession. Doing this ensures that your whole frame will have correctly exposed flash instead of just part of it. HSS is essential in situations and environments where you are shooting with a lot of natural light or you need to keep a fast shutter speed, or both. The X-sync speed on the Canon consumer DSLR's is 1/200sec I believe. So basically if you wish to shoot faster than 1/200 with flash, you need HSS.
For a budget up to £250 I would personally be looking at a
second hand Canon 580EX II which is very achievable. It is the best on-camera flash that Canon sells. Failing that, look for the Canon 430EX II, but the 580 is a huge improvement and when you absolutely need perfect results and have no second chances, I would want nothing but the best. Both the 430 and 580 have wireless receivers built in, but the 580 also has a transmitter built in so it can trigger other flashes too (including any Canon flash which has the receiver like the 430).
