strobe advice please

im very new to underwater photography,

that new in fact my housing is still in the post lol

been looking at strobes and need a little help

firstley, im a diving instructor and know quite a lot about (dry) photography, i have the canon 20-d, and should be recieving the ikelite housing in the next few days

i was going to get the ikelite ds125 strobe to utalise the ttl

what are the real benifits of running 2 strobes?

would a ds-50 and ds-125 combo work?

how would the ttl work in low light situations, or even on a night dive?

are there any books you can recomend

In short, the DS50 and DS125 combination does work, but is not the most flexible. The DS50 does not have built-in power settings and requires and external controller to change its intensity. This adds to the cost of the setup. Also, a number of situations require both strobes to have similar intensities, and the DS125 is quite a fair bit more powerful than the DS50.

As for your other question, there are a number of advantages in having two strobes: you can cover more grounds on wide angles, you can soften shadows on macro and portraits, you have a spare in case of problem, etc.

I can't comment about TTL, as I shoot only in manual, but I'm sure others will help you there.

As for books, check out the Essential Guide to Digital Underwater Photography...

thx for the advice, i have ordered the book

i am (after further advice) going to get one 125 and just get used to the system on a 60mm befour adding another 125, and going wide