I think you're entirely right about the light, but at this time I can't get anymore on the tank. There is already 135w of high efficiency fluorescent tubes on the tank! (I sometimes borrow the light rig for video) I am hoping to double it after xmas, maybe i'll get better results then. I'm also hoping to get a remote twin flash setup. I'll be interested to see how that pans out as well.
I'm having a very hard time getting any sharp results. the last is the sharpest i've had and that was really badly overexposed.
Ah well, more practice and intelligent use of advice should improve things.
200mm at f5.6 has plus minus 0.03 ft. A very very tight depth. 1/60 is way slow too. You need >1/250 for this lens. I am not sure this is the right lens for this subject.
I would try a different lens. 50mm 1.8 canon might be a good choice. You can buy for $100. Great lens. it would give you plus minus .5ft at 1.8 and allow 1/250 for same shot at f1.8. Faster shutter and more depth has got to be way better.
Cheers Scott, that's a great resource. Duly bookmarked!
I have the 1.8 50mm, mk I, but i'm beginning to suspect i've a duff/maladjusted copy(or ever present user error). it's just not as sharp as the 70-200, even stopped right down.
I may stick it on eBay and pick up another...