Canon t3i/600d vs Nikon d5100.

Soon i am going to buy a new underwater camera system. I am having trouble chooshing between the nikon d5100 and the canon t3i. I have read reviews about both and they both have pretty similar specifications above water.

Are there any major differences between them underwater? or can i get either 1 of them?

Also, im going to get either of them in the ikelite housing with the port for the 18-55 kit lens, and maybe invest in a ds-51 ikelite strobe.

Note: this is my first DSLR system so which of them would be easier to operate?

I don't have much feedback for shooting stills UW, as I am primarily a video guy; however, if you plan on shooting video with your SLR, the t3i has some features that you may find useful, including the option to shoot 60 fps at 720p (while the d5100 has a maximum framerate of 30p at any resolution). If you plan to shoot macro video, the t3i also has a neat feature that crops a portion of your sensor in order to get a 3x to 10x zoom without a loss of image quality; effectively making it possible for your 18-55 kit lens to become a 180-550. That's only useful for macro, but it's a cool feature.

Note that my only experience with this camera is topside; I've only used dedicated video camera rigs underwater.

The killer problem, with the cheaper nikons, is they do not have a built in focus motor.

This limits the lenses you can use. I believe the tokina 10-17 which everyone loves for underwater, cannot be used with the 5100.

Too bad, or I'd buy one.

So you suggest taking the canon one for when i expand to wide angle and macro shooting? And is there a big difference between the t3i and the t2i except the rotating lcd which has no use underwater.

The t3i has the video zoom feature I mentioned, while the t2i does not. Otherwise they are pretty well identical.

One nice thing about Canon cameras is that their lowest-end cameras are compatible with all of their EOS EF-Mount lenses, all the way up to the most expensive lenses. The lower-end Nikons, as derway points out, are only compatible with AF-S and AF-I lenses--AF lenses will meter, but will not focus automatically.

That said, Canon ain't better than Nikon, Nikon ain't better than Canon. There are plenty of great lenses available for each camera; it's all about which one has the right mix of features for you. Bottom line is that almost any camera body will take great pictures and good video if you know how to use it. Invest in lenses, not camera bodies!

Thanks a lot for the advice it was very helpful! Time to investigate for the casing and lighting options ^^