Canon saw the demand for a compact that would supplement those users who might prefer to carry a compact with them for those unexpected moments, yet still obtain high-quality pictures.
The original models came equipped with fast lenses, articulated LCDs, optical viewfinders, the facility to record RAW files and lots of external controls, and were aimed at tempting enthusiasts who usually shot with 35mm film SLRs to dip a toe into the brave new waters of digital photography.
The G9 became popular with underwater photographers, and this has continued right up to the G12, despite the on-going popularity of smaller cameras such as the sibling S-series.
Then Canon brought out the G1X. This was intended as a supplementary camera for those who had a DSLR, and it employed a huge sensor (almost DX-size) for stupendous-quality results (for a compact), and was correspondingly more expensive.
However, its close-focusing set-up meant that it was not suited for those who wanted to take the sort of macro pictures we look for under water.

The Camera
Now we have the Canon G15, which has reverted to all the features and functions that made the G-series popular with divers in the first place.
Superficially, the G12, G1X and G15 do look very similar, although the G15 is much slimmer than both the others once its lens is retracted.
Canon has dispensed with the articulated LCD screen of previous models, something that is of no consequence once the camera is installed in an underwater housing.
However, it does have a remarkably quick auto-focus, which is something anyone who has waited for their camera to focus while their subject swims out of shot will appreciate.
In fact, the G15 has among the fastest response times for all its operations of any compacts now available.
The top dial allows you to select the mode you require. And besides the usual shutter-speed or lens-aperture priorities, and indeed the ability to hand over total control to the software writers at Canon, there’s the all-important ‘“manual” mode that we underwater photographers need.
You can also add a couple of custom settings or control the video options from here.
Once you’re in manual mode, the two important controls, shutter speed and lens aperture, are controlled from the command dial at the back and the knurled control wheel at the front of the camera.
Video shooting (run and stop) is operated by a unique button at the rear, while the stills shots are taken by pressing the big button just where you would expect to find it on the top.
The built-in flash can be left permanently up and on, and that is how you will need it to fire an auxiliary off-board flash (by slave sensor or by fibre-optic cable with a clip-on adaptor) should you choose to get one – and you will!
In macro mode, it provides a satisfyingly sharp image on its sensor at the same size as the subject, or even a little bigger.
You can always opt to shoot jpegs processed in the camera, but if you shoot RAW files you get complete control of the image later on a home computer equipped with appropriate software.
The downside is that there is a delay of a couple of seconds while the camera records the data, and you have to wait for it to do this before it takes another shot.
The G15 may not have the largest pixel count at 12.1MP, nor does it have the fastest lens on any compact camera.
That said, if a full range of external controls, responsive operation, ruggedness and portability are high on your list of priorities, the G15 is definitely worth considering.
So how does it measure up for use as an underwater camera For that, it needs to work inside an underwater housing.

Canon WP-DC48 Housing
The G15 dropped into the Canon WP-DC48 underwater housing in a satisfyingly neat manner. The hinged rear door is held closed on its single user-accessible O-ring by a large cam-catch, and it’s depth-rated to 40m.
The housing is built from heavy-duty clear plastic, and appears at first glance to give full access to most of the controls. However, you need to be totally familiar with the workings of the camera, because these external control buttons are by and large unmarked.
In macro mode, it will focus on subjects that are almost touching the rectangular front glass of the housing.
The immediate problem I encountered was that the all-important knurled control wheel at the front was not accessed in any way, so the only way to change both shutter speed and lens aperture while in manual mode was to go to the menu and re-assign the rear control dial.
Shooting under water, the lens aperture is used to control the effect of the flash while the shutter speed is used to adjust the ambient light and the depth of blueness of the water in the background once the front-light exposure has been determined.
This meant that operations became too cumbersome to be viable for full control. I was reduced to choosing a shutter speed before I entered the water and selecting the lens opening as I went, changing the power of the flash to suit.
Another way to do it is to go in with the lens aperture pre-selected, adjusting the shutter-speed for the ambient light and the ISO for overall exposure. Either way, it does reduce the options for creative photography.
If you use the built-in on-board flash alone, a diffuser is supplied that fits to the front of the housing. On the other hand, if you are using the in-built flash to trigger a more powerful off-board flash, you can adjust its power to a low output, so that the camera’s battery takes less of a hammering. There’s a blanking mask with a fibre-optic dock that fits over it.
The Canon WP-DC48 is a relatively inexpensive underwater housing solution for the G15.

Fantasea Line FG15 Housing
There are several other manufacturers of housings that make one suitable for this camera. I got my hands on an inexpensive one from Fantasea Line.
Also made from heavy-duty plastic, the Fantasea Line housing for the G15 looked more robust than Canon’s proprietary offering, simply because the front section is opaque and black. It proved slightly larger, too.
Fantasea Line housings are named after an early liveaboard (Fantasea 2) that operated in the Red Sea under the auspices of Howard Rosenstein.
Howard was a true pioneer of the Red Sea, who put the wreck of the Dunraven on the map and developed many of the dive-sites in that area that we now take for granted.
He now lives in Israel, and the fact that he knows about diving is revealed in the way this housing for the G15 is put together. It’s depth-rated to 60m, and begs comparison with the Canon housing.
That all-important front dial is accessed by a big rotating knob at the top of the housing, as are all the other controls.
All the black control buttons are clearly labelled with white lettering or icons that are easily understood.
There was no head-scratching or frantic button-pushing while this camera and housing combination were in use.
The knobs are offset from the camera buttons they are required to press, which means that they are less cluttered together than they might be, and as they inevitably are on the WP-DC48.
Dropping the camera into position means raising the mode command control of the housing to accommodate it, and I first thought that I might have needed to add a little adhesive pad so that it engaged better, but once pushed down by water pressure this was not required.
The hinged rear door is sealed by double O-rings, one in the door and one retained in the housing. The door is kept closed by an over-sized rotating cam-catch.
It all looks very secure from unintentional ingress of water, and there’s additional security from an electronic leak detector with sensor patch at the base of the housing, a red LED warning light and audible alarm.
Other details that betray Howard’s diving credentials are the fact that you can put the in-board flash of the G15 up and down remotely and at will, and that the LCD has a deep hood that can be fitted to provide shade from the bright Red Sea sunshine that can make LCDs of compact cameras almost unviewable.
Both housings have rectangular front ports that would seemingly deny the use of option accessory lenses, but Fantasea Line offers own-brand close-up, wide-angle and fish-eye adaptor lenses that fit.
The FG15 also comes with a huge diffuser that fits onto its front and allows use of the camera’s in-board flash alone.
If you opt for the better solution of an off-board flash, the mask that slots onto the flash port of the housing has two fibre-optic take-offs for up to two off-board flashguns.
In total, the Fantasea Line FG15 is a robust and fully usable underwater housing solution for the very able Canon G15 compact camera to make great stills or video clips.
There are also more expensive plastic and aluminium housings available for the Canon Powershot G15.

PRICE Canon G15 Powershot camera, £400 - £550 according to retailer. Canon WP-DC48 housing, around £250 according to retailer; Fantasea Line FG15 housing, around £450 with two-year warranty.
SENSOR CMOS 1/1.7in 12.1MP
ISO Range880 - 12,800
LENS Max aperture f/1.8 – f/2.8 according to zoom
FLASH MODES Auto, On, Off, Slow Synch, Second Curtain Synch.
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