ScubaRon:
Since the lakes here are barely unfrozen, I am practising in my reef aquarium. Stationary objects are OK (see pics), but the shutterlag makes it very hard to make good pics of fast moving fish. Any tips regarding this are very welcome.
First off, congrats on the rig. I have the D180 - it rules.
Next - dude, are you like using a snorkle or are you tanked up in that reef aquarium? Just curious. With your full rig you'll get a chance to dial in your buoyancy with the rig. It'll shorten the learning curve for when it ices out soon. Just a thought.
Last - Fish butt... I'm a pro at that one - the undisputed king of fish butt. See a cool shot, compose, pull the trigger, fish butt. I got zillions of them. That's why, as I'm getting the rig dialed in I'm taking lots of pics of things that move slow - stars, slugs, fans, anemones, etc.
Other UW photographers with much more experience will chime in at a more reasonable hour - but the way I get around fish butt (sometimes) is by anticipation and pre-setting.
Not sure if the 750 can be pre-set, but with the 5050 I can dial in E & A as well as zoom length - so when its fishie time, I go to my pre-set #4 - about 31 inches. I know if I'm 25 - 36 inches, I'll get the shot (if he's still there.) With pre-set, I can see the subject (picture me swiming along all nonchalant...) and sort of make the turn and pull the trigger on approach, and by the time I get within range, the shutter lag has expired and before fishie knows what's going on, I get the shot. I'm getting better with it.
You're going to love the rig!
K