A report on my first experience of submerging AU$5000 worth of camera gear in a crappy plastic bag...
Yesterday was an exciting day for my 10D, as it finally got to go underwater. To add to the excitement, the trip was made in a second-hand EWA-marine plastic bag!
For anyone who hasn't seen them, EWA-marine housings are made of heavy duty soft plastic, closed with a metal clamp with three screws and with an optical glass port on the front. The attraction is that they will fit any camera (in the case of my U-AX model, just about any SLR and lens should fit), and the price, at US$105 in this case, is an order of magnitude less than a 'real' underwater housing.
I'd read a few reviews of them on the net which suggested they were probably good for keeping rain off your camera, and a fair few negative comments on forums, generally from people though who hadn't actually used one.
The primary purpose of the trip was to test my buddy's new dingy, but as my Ebay-purchased EWA-marine arrived this week I figured it was a good chance to test it and see if it leaked.
As there were no obvious large holes in my new housing, I loaded my beloved 10D into it and made sure the metal clamp was suitably tightened. A quick test submerge showed no telltale bubbles escaping, which I figured was a good thing.
The test site was off Jardine Island, in the Dampier Archipelago off Australia's remote northwest coast. This isn't a recognised dive site, but the Dampier Archipelago does contain some excellent coral elsewhere along with large marine life.
Snorkelling off a rocky point near where our dingy was moored revealed a fairly good selection of fish. We almost ran over a sea turtle in the boat, but I didn't have the opportunity to snorkel with one on this occasion.
First thought about the EWA-marine:
I works pretty well with Canon's 17-40L, which fits snugly against the glass of the housing. Vignetting was a problem if the housing wasn't centred well (at 77mm filter diameter this lens is technically to wide for the housing, but physically fits much better than smaller diameter lenses), but I think I can pad it with a piece of foam next time so I don't need to remember to physically hold the plastic housing onto the lens.
The 17-40L, BTW, would seem to be an good choice if you're using a Canon D30/D60/10D in general underwater use, as it's excellent at 17mm and this is about as wide as you're likely to get with a reasonably priced Canon lens,. The 15mm Sigma prime seems to be a popular choice also. Using lenses which are physically smaller was a bit annoying, and the lens will be a long way from the glass plate of the housing, which is probably not a good thing.
2/"Strobe" - with this housing is with a flash gun mounted in the plastic bag, in this case a 420EX Speedlite. This does give full E-TTL automation, but the strobe is still a bit close to the plane of the lens. Visibilty was not good on my test day (big tides up here stir the water up plenty), and backscatter on most of my test shots was horrible.
3/Ease of use: The viewfinder on the 10D is small to begin with compared to film SLRs, and it's very hard to use with a mask and plastic housing combined to obscur it. The advantage of the soft plastic housing is that it allows me, with difficulty, to use all the functions on the camera, as all the buttons are accessable. The disadvantage is that it's clumsy to access small buttons throught thick plastic. In addition, EWA-marine have cleverly placed a large opaque white model description plate directly over the place where the LCD of a DSLR sits, making it impossible to read. I suppose they figured no-one would be crazy enough to put a perfectly good DSLR into one of their hoiusings...
In summary, this is no match I'm sure for a proper hard housing, but I and many others can't afford one, at least not this week anyway.
Another way to look at it is that for a set-up cost of $100 or so, this gives me an underwater camera setup that has the capabilities to provide quite good results, at least on a good day (I'm planning on using it mainly for snorkelling as most of the reef around here is pretty shallow, so available light should be reasonable). As a downside, I haven't heard much from users who've actually used one of these whilst diving on SCUBA. I'm still working up the courage to try taking my 10D/EWA-marine down with a tank on, but it is rated to 30 foot.
Any comments, including from anyone who's used this housing or has a better idea for taking Canon DSLR's underwater, would be greatly appreciated!
therefore providing many more ways for me to screw up a good shot or worse delete it! 
