birdpix wrote:
I own a Yongnuo 560 and it works well. It is a manual flash, as has been noted, and it fuctions well as a slave. It is cheap enough at around $72 to own several of them for studio work. For on camera flash though, the lack of ETTL metering would be a setback. Why waste all that high powered flash circuitry in the camera when you are not in a studio setting and you and your subjects may be moving around?
Just to make it clear to the OP; the unpredictable and varying distance of the subjects to the flash is what this poster is referring to; not necessarily that you be shooting in a studio setting or not. If you are photographing something where you can shoot a shot and adjust the flash power to get it right; be in in a studio or on a location, then a manual flash is fine, but if you are (for example) at a party where the known distance is always changing from flash to subject and you are taking impromptu shots then ETTL is a must.
I hope that's more clear.