AleG
Contributor
I'm thinking of buying a S&S YS-27DX strobe to go together with my Canon G11 camera, I'm tired of having so much "snow" on my photos from using the camera flash. 
I haven't used an external UW strobe yet so I'd better start to get a grip on the matter before I start spending money on it.
First off, I'm not sure about the YS-27DX sync cable, I assume it simply triggers the strobe but it doesn't sync the duration of the flash, the strobe just fires whichever manual setting was dialed in, correct?
I've eyed the YS-110a because my understanding is that it can actually sync the flash pulse to the camera metered flash, so it doesn't need to be manually adjusted to get the appropriate exposure, again am I correct?
So, assuming I have the YS-27DX, and I want to shoot something I should adjust the strobe strength based on some charts or is it one of those things one learns by trial and error?
To be honest I'm a bit torn between either the 110 or the 27, but I don't know if the difference between the strobes is worth the price considering it's going to be used with a WD-34 case and a fiber optic sync cable; so if you can weight in on the merits of choosing one or the other you are welcome.
Any suggestions and input would be very appreciated, I'm going on a live aboard trip to the Similan and Surin islands on New Year so I'd like to have my camera gear ready by then.

I haven't used an external UW strobe yet so I'd better start to get a grip on the matter before I start spending money on it.
First off, I'm not sure about the YS-27DX sync cable, I assume it simply triggers the strobe but it doesn't sync the duration of the flash, the strobe just fires whichever manual setting was dialed in, correct?
I've eyed the YS-110a because my understanding is that it can actually sync the flash pulse to the camera metered flash, so it doesn't need to be manually adjusted to get the appropriate exposure, again am I correct?
So, assuming I have the YS-27DX, and I want to shoot something I should adjust the strobe strength based on some charts or is it one of those things one learns by trial and error?
To be honest I'm a bit torn between either the 110 or the 27, but I don't know if the difference between the strobes is worth the price considering it's going to be used with a WD-34 case and a fiber optic sync cable; so if you can weight in on the merits of choosing one or the other you are welcome.
Any suggestions and input would be very appreciated, I'm going on a live aboard trip to the Similan and Surin islands on New Year so I'd like to have my camera gear ready by then.