Need help with my new Canon 400D

For many years I have been shooting an Olympus 50-50 in manual mode with great results. I recently made the jump to a new Canon Rebel xti with an Ikelite housing and a DS-125 strobe.Although I have on order a Tokina 10-17 I am currently shooting the 18-55 that came with the camera. My problem is this...the pictures suck. Because I am used to shooting the Olympus, I started with my old standard settings.f 5.6 at 125 Normally I use the shutter to controll the background and change the f stop to reflect the distance to the subject. I cant seem to get a good dark blue background in any of my shots, something I found ever so easy with my old setup. They all seem to be over exposed or just dark, but not blue. Are there some in camera settings I'm missing?

I am currently shooting the 18-55 that came with the camera. My problem is this...the pictures suck.

Hi NMJ, My son shoots the 400D and he's had some great luck with it so far. Your issue could come from a lot of things I guess, and it's hard to diagnose without some more info. Where were you diving? Vis.? etc. What kind of images were you attempting? If you could post some shots it might also help.

My first guess though is that you have already solved the biggest part of your problem by getting the 10-17mm. You will see a night and day difference. It's a great lens. I will tell you though that when you first use it you will have a tendency to be too far away from your subject. You will need to get much closer than what your used to.

I went back and looked at Jeff's images from the last trip with his 400D and his settings tended to cluster around f8 and 1/125th at ISO 100 with surface blue water in the background. This was in the Bonaire's crystal clear water on sunny summer days. The proper exposure though is going to change all the time. We use the camera to meter the general area we're going to shoot with the same sun angle and tend to setup the camera about a half stop under the meter reading. We then take a shot and use the histogram to adjust from there. I'm not sure about the Ike ports for the 10-17mm, we use the big S&S fisheye dome. The only other thing I can think of to recommend is that you shoot RAW so if you're a little off you can tweak it in Lightroom or ACR. Hope it works out for you.

Steve

Good advice from Steve. You'll be needing to use higher F-stops with the 400D because of its larger sensor. You can get away with F4 and 5.6 on the Oly because of the differences in depth of field and because it has such a short focal length. With the Canon you'll need to regularly use F8 to F16 to get good shots, but you CAN because of its high ISO performance (try 200 and 400 if you need it).

Another reason it's harder to get dark blue water is that you can use like a maximum of 1/200th if you have a flash connected (might be a little faster, can't remember). This will somewhat limit your ability to get dark water. Since the Olympus has an "electronic" shutter, you can use flash at virtually any speed.

Cheers

James

Thanks for the post Steve. I live and work on Grand Cayman. The water here as you well know is very clear. The only difference I can see straight away is the iso. I had it on 400. I have a 6"dome port for the housing so I'm hoping the Tokina will fit. I'm gonna head back out this afternoon for round two.

The ISO400 probably explains it. I bet your camera was giving you a SS ceiling of like 1/250th of a second - so you couldn't get dark water.

Cheers

James

Thanks James. I think it's 1/250th. Is there any way around this? Maybe shoot the strobe in manual?

Thanks Again. I will try dropping it down to 100.

Thanks James. I think it's 1/250th. Is there any way around this? Maybe shoot the strobe in manual?

Say Hi to Neptune for me! The canon site shows a 400D(XTi) sync speed of 1/200th. The 40D is 1/250th.

Steve...will do.