so, on the d200, im powering a sb600 via the preflash, and i dont have a full understanding of cls but i think there is two types, one via preflash, and one via infrared? is this the case? ok, so obviously on the d200 i have to use preflash, but im just wondering in outdoor situations with very bright natural light do people tend to have issues with cls working properly or is this not an issue? (coming from the idea of flash exposure matching available light exposure causing the flash units not to detect a different or something, i dunno if im wording this right) also, is anyone able to explain how just with a preflash how the camera transfers the settings info set from the camera to the flash? and for that matter 2 different groups of flashes(i havent done this yet, but it just boggles my mind and to think the with a su800 i can control 3 groups i think it is?) im thinking it might just be one of those dont ask questions, just be happy its awesome and works sorta things... but thanks to anyone who can bring light to any of this stuff.