Combining my scuba diving hobby with photographing made huge advances to both of them.
When extra pile of money appeared at the beginning of 2002 I acquired Canon G2 digital camera and ordered a housing for it. Now I've used it for three summers at the waters of the Baltic Sea.
Canon G2 digital camera has 4 megapixel sensor, full manual controls and feet for external flash. Camera is not a SLR and there is no possibilities to change lenses. It is more like large pocket camera, but its quality of pictures have been generally considered quite good.
Link to Canon G2 review at Dpreview.com
Housing has been made by UK Germany (UK = Uwe Klein). They make aluminium housings from many film-SLRs and nowadays also for several digital cameras. UK Germany has said to be a quality maker, but because of their small series their prices are higher than for example Ikelite has.
Ikelite makes also housings for G2. Their housings are made from polycarbonate and would have been cheaper (although as good). My choise was affected by full E-TTL -support for flash (Ikelite has only slaves) and also good service from UK Germany and easy money transaction inside EU. Finally I also found webpages of Thomas Hopfner, where he told experiences with the same housing and Canon G1.
UK Germany promises 2 months delivery time (they make housings when they are ordered). For me it too almost 5 months because they had to redesign the housing from G1-version.
Thomas Hopfner's web-pages (in German).
Housing has been primed from two pieces of aluminium and hard coated. There is large o-ring between the pieces and two clips keep them together. Camera is tightened to housing with tripod screw. Size without grip is 180 x 150 x 85 mm. Structure is simple but feels quite strong.
UK Germany promises that housing can handle pressure till 80 meters. Housing has mechanical buttons to all controls of G2 except manual focusing. There is cable connection for flash. Both LCD:s have their window. Optical viewfinder is not possible to use.
Lens port can be changed. At least there is longer port for Canon wide angle or tele adapters. Lens port is flat - I don't know about availability (or usefulness) of dome port.
Housing has hand grip and footing for flash arm. At the bottom there is mount for tripod and two drillings with M4 (?) threads. At the top of handle there is drilling with M6 (?) threads.
Flash is Canon 420EX with aluminium housing. Housing seems to be very general and 550EX might also fit in it. Tube shaped housing has glass front and plastic back. Flash is set to point upwards and foot is put to backcover. Housing is 220 mm long and 100 mm in diameter.
Flash arm is not made by UK Germany but bought from Kilgus. It has two ball clamps, which gives quite good possibilities to set flash different positions. Above water clamps don't feel enough stiff, but under water they work fine - they keep flash on the position, but they can be moved without loosening and tightening them.
Flash cable and its connectors seemed to be reliable. Connectors have three o-rings each and they seem to be tough. There is connector to flash feet inside the housing.
Seems that tightness and water resistance is based on o-rings. They are instructed to lubricate regulary with silicon grease and check for hairs or dust every time housing is put together. There has been no problems with the water at these three years.
Housing with camera has slightly negative buoancy under water. Flash housing is slightly floating but with arm the whole package is negative. Handle and flash arm gives you a good grip. Above water flash arm can be used for carrying. Shutter lever can be easily handled with the thumb and it is possible to press shutter halfway down to make measurements before actual shoot. Other controls are mostly press buttons and can be handled quite well underwater even with gloves.
Price for Canon G2 was around 1000 euros when I bought it, 420EX is still about 260 euros, and UK Germany housings with arms and cables cost bit over 2000 euros. Prices of digital cameras are dropping - housing prices probably not.
Housing from Ikelite would have cost about 750 dollars plus 500 dollars for the flash plus something for the arms and cables. Without external flash you could get a housing for pocket digital camera at 200-300 dollars.
Links to web sites presenting housings for digital cameras:
First thing to understand in my case is that I dive mostly at Baltic sea. It is small, not very deep, water has less salt than oceans and the visibility is basically poor. So problems with light are even more complicated than normally. Also targets are quite different. Baltic sea has quite a small selection of vegetation and animals. But because the low salt and no boat worm (teredo navalis) all the wrecks are in good condition.
So Finnish underwater photographing has lot of problems. If you go deeper than 3-6 meters there is normally not enough light. If there is, all available colours are green and green. There is normally lot of particles or clay at the water which either prevents visibility or at least shows at the flash light. (I really wait to visit some clear waters with my camera.)
All underwater photography has basic problem of keeping motionless when taking pictures. Low light conditions require longer shutter times and it is not easy to stay steady when 'flying' at the water. In principle water decrease vibration of the camera when taking pictures, but because shutter lever is made to use with gloves, it also moves camera easier.
Using digital camera does not help any of the problems above. Actually digital cameras have had more problems in low light conditions. G2 can make good results in low light, but not any better results than film cameras. The main advantage with digital camera is possibility to see picture taken already underwater and maybe take another shot if necessary - and if the fish is still there.
Other advantage with G2 is that its batteries have long life, even 2-3 hours with LCD on. Because I have 1 gigabyte microdrive in camera, picture storage is practically endless. Flash seems to have power for at least one long dive, I haven't yet have it powered out with fresh batteries.
Camera controls are usable even with dry gloves. Only problem has been the zoom lever. Camera has zoom lever which you turn either side to have wideangle or tele. It returns to center position when you release it. With housing zoom lever can not return to center position. And if the the lever is kept turned other controls and shutter are locked. It is very easy to push zoom lever accidentally and this will cause that shutter will not work at critical moment.
At the first dive I found out, that it is not possible to direct flash without some guide light. I got small battery lamp and tightened it to flash housing with rubber bands. Light also helps camera focusing and work even as a dive light. This have been good solution for now, but I have plans to build guide light inside the housing.
Directing the flash has required practice. When taking pictures of something near, it seems to be best to direct flash from above target. And when targets are further, flash should be as far from camera as possible. By putting flash arm ball clamps to right tightness, arm can be turned by hand to right direction. For macro photos flash can be turned quite near to lens.
If you basically know how you would like to shoot, it is easiest to direct flash beforehand. Just approach target until the guide light is at middle of LCD and press the shutter.
If you have flash connected and on, it cannot be turned off - there is no controls at flash housing. Because camera has E-TTL -control it knows it presence and you cannot take longer exposures with full automatic exposure metering. Solution to this is to switch camera to time setting (Tv) mode and set exposure time by hand. You can use flash as a fill flash or motion stopper or you turn flash away and use only available light.
If the target is small, you need to get near and use macro-mode of the G2. I've found easiest to put camera into macro and zoom to full tele. Then you can focus to 20-30 cm but you can still use flash especially from above. Area of focus is very small and automatic focus of the camera has to be checked from LCD.
Only control missing from housing is manual focus distance setting. There might be use for this in macro photos, but manual focus in G2 is so difficult to use, that I don't feel this as a great loss.
Macro pictures is easier to take than with film, but the wide angle is the problem. Because of the small sensor it is not cheap to create a digital camera with nice wide angle. It would help at Finnish waters to get close enough. There are wide angle adapters available for G2 and there should be longer port for them, but I haven't had chance to test these.
Best thing when using digital camera underwater, is that you can take enough pictures and then choose the best ones. Until now I have selected about 10% of the photos taken to show them to others. Most of the times reason for dropping the picture has been incorrect focusing.
One of my own reasons for digital photographing has been possibility to adjust pictures afterwards. I do not respect photos as one time opportunity to freeze situation. I crop pictures and correct exposure and color problems.
Underwater pictures are no exception. With the flash I normally get enough light, but I'd like to see pictures as I see them underwater. So I normally remove Finnish green colors and add some contrast. Also I have tested of removing particle 'noise'.
Beginning from the second summer I have tested changing the color temperature at the camera. I direct the camera to mid-water and use G2:s custom color temperature function. Results have been very promising. Pictures can be used with minimum adjustments - normally just adding more contrast with levels-function. There is less noise and higher ISO-values can be used.
I also have tested using tripod under water. When water has been clear, it is possible to have very impressive photos with shutter times like 1 second. Customizing the color temperature is needed and of course you cannot photograph moving targets.
At 2004 I've taken quite a lot of pictures with the tripod. Shutter times have been up till 15 seconds. Results have been very promising. With clear water you can have exellent landscapes even at Finnish waters. Wide angle lens would have been excellent tool. Seems that somehow I should really get my DSLR underwater.
Some of my UW-pictures