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Editor's Note - This guide was originally written for using the G11 and S90 in Canon housings. That said, the G11 and S90 and almost identical to the G12 and S95. Follow this guide whether using a G11, G12, S90 or S95

By Willliam Tan

When Canon approached me to test shoot their PowerShot G11 , I agreed without the slightest hesitation.

A strong believer of digital compact cameras being easy to handle, be it on land or underwater, I arrived at Gorontalo (Indonesia) with the camera and housing still sealed in the original box, untouched. In order to simplify things and shoot with the camera’s auto mode, I came up with what I thought a “fool proof” plan of using a powerful white beam torch as my light source.

On site testing showed that I couldn’t be more wrong - the G11’s 28mm built-in lens was so wide that the resulted images appeared to be shot with a strobe on a narrow snoot. Part of the subjects that were lit by the torch's beam appeared overexposed under the torch’s “narrow” beam, and the background remained dark.

When I turned to using the camera’s built-in flash as the main light source, the large nose of the housing (WP-DC34) blocked the flash, and cast ugly shadows that threatened even to cover my subjects.

Not ready to admit defeat, I dug out an old YS90 film camera strobe from my Pelican cases, and set it to
slave mode (A slave strobe will only fire when it “sees” the camera’s built-in flash firing). Since my old YS90 was built before the time of digital cameras, it cannot sync with G11’s Auto, Shutter Priority, or Aperture Priority modes, but was able to sense the camera’s built-in flash when a correct shutter speed was chosen on the camera's Manual mode.

Other problems surfaced along the way, but the instruction manual booklet provided answers for all the questions when you looked hard enough. It took me several days before I was able to get my first satisfactory image; the effort of thoroughly studying the instruction manual booklet was surely worth it.

Canon was happy with the final resulting images, and decided to have me to test shoot their PowerShot S90 a month later. I found that the functions on S90 to be very similar to G11, except it lacks the built-in ND filter.

Having ironed out the initial glitches and bumps of learning how to use the G11, I set up the S90 in the exact same way, and the results were similarly satisfactory.

The secrets to my success with these cameras are in the camera settings. The following were used for my G11 images. You will be able to find all the same functions (except ND filter) in S90 too.

These settings had worked for me when shooting with a single external pre-digital-period slave strobe in Manual mode. They are not to be thought of as the only correct method to use the G11 / S90 underwater.

Menu – Camera icon

Digital Zoom – off
Digital Zoom is accomplished by electronically enlarging a desired area of your image. This method creates noise in the resulting image.

AF-Point Zoom – on
Half pressing the shutter will allow this function to enlarge the center focusing area when the subject comes into focus, thus allowing easy viewing.

Servo AF – off
This function needs to be switched off for AF-Point Zoom to be turned on.

Continuous AF – on
It will be helpful to keep this function on. It allows the camera to set focus continuously no matter where you point your lens without half pressing the shutter button. Less searching time is needed for the camera to set and lock focus when you finally half press your shutter button to take the image.

AF-Assist Beam – off
Your housing will block the beam, so it is useless to turn it on.

MF-Point Zoom – on
It enlarges the center focusing area for easy viewing at all times when shooting in manual focusing mode.

Safety MF
This refines the manual focusing when the shutter is half pressed.

Flash Control
If you are shooting in Manual Mode, set to a minimum power that is still strong enough to trigger your slave strobe(s) to save battery life.

i-Contrast – off
This function is useless unless you are shooting in Auto ISO mode. However, Auto ISO is undesirable. You will get noise in your images when the camera automatically chooses a higher ISO in dim underwater environments.

IS Mode
The IS (Image Stabilizer) might be helpful if you are shooting at slower shutter speeds, when there is a surge, or if you have a constantly moving object.

Record RAW + L – on
This function allows the camera to record simultaneously a RAW file + a large Jpeg file with every single image taken.

It is advisable to shoot in RAW. It gives you the best image quality your camera can produce. Jpeg is a compressed file. Every time you resave a jpeg image, you are compressing it further, thus losing more details in the process.

 

 

 

Menu – Tools icon

LCD brightness – highest
One of the problems that is most frequently encountered in underwater photography is  your strobe(s) being over powering, causing overexposed images. Underwater and with the sun’s glare reflecting on your LCD screen, the display is never accurate enough to judge your exposure. What seemed acceptable underwater on your camera’s LCD often became overexposed when viewed on a proper computer screen.

Adjusting the camera’s LCD brightness to the highest will bring your attention to this problem. Should the resulting images become slightly too dark due to a brighter LCD screen, Photoshop will be able to bring the exposure up to what is desirable. On the other hand, Photoshop is unable to put details back into overexposed images.

Function Set

White Balance – AWB
When shooting with external strobe(s), there is no need to set the White Balance to Underwater mode - the resulting color will be wrong. AWB (Auto White Balance) will allow you to cope with most underwater situations.

Nevertheless, if you shoot macro at very close range with external strobe(s), there is a good chance you might get an ugly yellow hue on your resulting image. Canon has solved this problem by allowing you to further adjust the White Balance in AWB mode. By pressing the DISP button when you are already on White Balance function, a display grid will pop up. Pressing the left (macro) button on the Control Dial will move the White Balance towards blue color to neutralize the yellow hue.

My Colors – off
Color adjustments built into the camera systems can never be as accurate and refined as what is achievable from the Photoshop software. It is safer to shoot your images without any color adjustments from your camera, and then work in the desired colors using Photoshop.

BKT – off
Since it is possible to see the resulting images on your camera’s LCD screen, there is no need to BKT (Bracket) your exposures. Moreover, unless your external strobe(s) allow you to shoot in TTL mode, the camera’s built-in flash will not be able to change the power of your manually adjusted external strobe(s).

Flash Output
Set a minimum power that is strong enough to trigger your slave strobe(s) to save battery life.

ND filter (not available on S90)
Every strobe has a minimum power output level. Should this minimum power output level prove too strong for your camera settings, thus resulting in overexposed images, it is time to turn on the ND (Neutral Density) filter. This dark filter will cut your exposure by -3 stops (one setting only). It is also useful when you want to achieve a black background instead of getting blue water.

This lionfish was swimming near a coral wall. The ND filter had cut down the weak ambient light reflected from the coral wall by 3 stops so that it appeared black. I increased the strobe power to keep the lionfish correctly lit.

Though the S90 comes without a built-in ND filter, a black background can also be achieved by going deeper with the camera’s limit of only f8.

Single Shot / Continuous / Continuous AF

•    Single Shot - half press shutter to focus for every shot. (This is the function I shoot with)
•    Continuous - camera shoots multiple frames with the focus locked at the distance of the first shot.
•    Continuous AF - camera shoots multiple frames, lens will attempt to refocus between shots.

RAW
Records RAW and large jpeg files for every frame shot.

Top of Camera

ISO – 80
This lowest ISO number will give you minimum noise in your resulting images.

Images are not only sharper, but also richer in colors when a low ISO number is selected.

Control Dial

Flash button – on
You will need your camera’s built-in flash to trigger your external slave strobe(s).

Macro button
Allows you to achieve a closer than normal focusing distance.

MF
Manual focusing might be useful when you use a super macro lens attachment.

other functions

AF Frame Selector (top left of the Control Dial)
When selected, the displayed AF frame will turn orange. By pressing the up (MF) / down (timer) / left (macro) / right (flash) buttons on the Control Dial, you can move the AF frame to a place of your choice on the LCD display. Holding down the AF Frame Selector will reset the AF frame to center.

Pressing the DISP button when on this selection will make the AF frame smaller for more accurate focusing (spot focusing).

Light Metering button (top right of the Control Dial)
Allows you to switch selections between Metering / Shutter Speed / Aperture functions.

•    Evaluative Metering - useful for wide-angle images as it takes into considerations the entire blue background as well as your subject(s) for correct exposure (useless when you are shooting in Manual mode).

•    Spot Metering - preferred for macro images since it can then disregard the black or white sand background and expose your tiny subject(s) correctly (useless when you are shooting in Manual mode).

•    Shutter Speed - you need to find out at what speed your slave strobe will be able to sync with the camera’s shutter curtain. Most macro subjects can be captured between speeds of 1/60 – 1/250. Depending on conditions, you might want to attempt even slower speeds for wide-angle shots. Too fast a shutter speed will result in partially black frames.

•    Aperture - for macro images, you might want to choose the smallest Aperture possible (f8) for a better depth-of-field. With wide-angle images, you will need to move both Aperture and Shutter Speed readings to get a blue background that is pleasing to you.

In certain housings (the original Canon WP-DC34 housing included), there is no built-in gear to access the Control Dial. Nevertheless, there is an alternative way to get around this “problem”. By keeping the Short Cut button (top left of LCD screen) depressed and simultaneously pressing the left (macro) / right (flash) buttons on the Control Dial, you can change the readings as if you are using the Control Dial.

Shooting in MF mode
With added macro attachments, when the camera’s auto-focusing system is challenged, Manual Focusing (MF button) might be worth considering.
Keeping the Short Cut button (top left of LCD screen) depressed and simultaneously pressing the left (macro) / right (flash) buttons of the Control Dial, the focusing distance can be adjusted.

Finer adjustments can be achieved by manually moving the entire camera body, or even your own body.  Remember to turn on the enlarged focusing area in the LCD screen.

Problems encountered when shooting underwater

Camera nose
The large housing nose will block the camera’s built-in flash. Subjects will appear dark or unlit if they fall within the “shadow” created by the nose.

This was shot only with the camera’s built-in flash. The flash was strategically placed on the camera’s lower left corner, yet it failed to light up the tip of the sponges.

Strobe power
Although most strobes have knobs to adjust the settings of output power, further “adjustment” of this output level can be achieved by moving the strobe closer / farther away from your subject.

I covered the outer diffuser in front of the camera built-in flash with tape, so that the built-in flash does not cause backscatters.

Exposure - Metering and strobe settings

Do not expect to shoot with a correct exposure setting on your first image on any chosen subject. I usually take a few test shots to check the exposure. With every test shot taken, the aperture, shutter speed and strobe power settings will be adjusted to what is desired. When I see my exposure corrected from the LCD, then I start to compose my shots.

Shooting with a single external strobe
With only one external strobe, you will get a shadow no matter how you position your storbe. However, if you place the shadow intelligently, the image can appear surprisingly pleasing.

Both images showed a harsh shadow under the fish. If 2 strobes were used, they would be able to cancel out each other’s shadow.






To zoom or not to zoom
Unlike fixed lenses on DSLR cameras, if you should utilize the G11’s wide-angle to set focus at its closest camera-to-subject distance, your subject(s) will appear very small (wide-angle lens). By zooming out and finding your new closest focusing distance (now farther) not only allows the subject(s) to appear larger (as in telephoto lens) on the screen, but also gives you a workable distance to place your strobe(s).

Sunburst
Digital cameras, especially compact cameras,  have problems recording sunbursts. To avoid burnt-out areas, it is best to hide the sun behind your subject(s).








Lens Attachments (Wet Lenses)
When using dedicated attachments in macro and wide-angle filters and lenses, you need to zoom out to avoid the “black circle” that will appear on the corners of your frame.








Shutter delay
The S90 appeared to be slower than G11.

This clownfish has a deformed fin just like Nemo. I had to time for the clownfish to fold both its fins in order to get an image showing both fins displayed.

Below are more images shot using the settings and techniques from the guide. Enjoy.