Homemade Combination

Fiber Optic Slave Strobe Cable Attachment

&

Camera Strobe Deflector

for the Canon WP-DC28 & WP-DC34 Housings

(G10 - G11 - G12 Cameras)

This is a simple, lightweight, inexpensive device for attaching a fiber optic cable to the housing. It also serves as a deflector to block the cameras built in strobe. Blocking the camera's built in strobe is necessary with the WP-DC28  and WP-DC34 housings as the strobe does not cover the entire photo when shooting very close to a subject. If you do not block the camera's strobe on close-up shots you will likely have a "hot spot" on the portion of the photo that the camera's strobe covers. The device removes quickly and easily and also allows the use of the cameras built in strobe for desired circumstances. The device may be suitable for other Canon models as well as other brand housings. The WP-DC28 housing was used in this demonstration.
Materials and tools needed:
1 -  Dark colored plastic box that does not allow light through it. The box must have a right angle between the bottom and the side or on inside compartments.
2 -  3/4 inch wide Velcro strip with self adhesive on the two halves (crafts section of Walmart).
3 -  small hacksaw with fine tooth blade or equivalent tool.
4 - Super Glue, silicone or other strong waterproof adhesive/glue.
5 - sandpaper, medium grit, 180 is fine.
6 - Rubbing alcohol to clean parts before gluing and applying Velcro.
STEP 1 - Cutting out the section of box
This box is rigid and has right angles at the bottom and sides and on sections inside. I purchased it in a supermarket while in Bohol, Philippines. Cut out a right angled section of your box that measures 5/8" X 1 1/2" X 2 1/2" long. The 5/8" side will attach to the camera housing with Velcro.
You should end up with a section that looks like this. Sandpaper the surfaces shown in preparation of attaching the Velcro and fiber optic cable. Smooth the cut edges and round the corners to your satisfaction.
STEP 2 - Cutting the Velcro
Cut a 1 and 3/4 inch length of Velcro from the strip. Do not expose the adhesive parts yet.
STEP 3 - Attaching the Velcro to the camera housing
Attach one of the two sections of Velcro to the housing. Be sure the area on the housing is clean and dry. DO NOT use the rubbing alcohol on the housing to clean it. I attached the "softer" portion of the Velcro to the housing. Start attaching the Velcro just past the curve of the settings dial on top of the housing with the edge against the front of the flash area. The 1 and 3/4" length is enough to cover the flat area of the housing before it starts to curve around to the side.
I chose a design that attaches to the top of the lens tunnel versus in front of the camera's strobe area because it is a flatter area as well as has more surface area to work with. This design allows for easy removal of the device for picture taking with the camera's strobe, such as topside shots without using the slave strobe.
STEP 4 - Attaching the Velcro to the device
Wipe the Velcro mounting surface clean with rubbing alcohol and let it dry.  Apply the other half of the Velcro strip as shown below. Be sure to apply the Velcro to the correct end of the device. Trim off the excess Velcro along the edge as the Velcro is 3/4 inches wide and the device is 5/8 inches wide. There will be an area that the Velcro does not cover. That area overhangs the curve of the lens tunnel to help block the camera's strobe.
STEP 5 - Preparing the fiber optic cable
Cut the end of the cable at a 45 degree angle so as to better expose the area of the cable  that receives the light from the camera's strobe. You only need to expose about 1/8 inch of the cable.
STEP 6 - Mounting the cable to the device
Attach the device to the housing and mark the spot where the cable will be centered in front of the camera's strobe. Remove the device from the housing. Wipe the cable mounting surface clean with rubbing alcohol and let it dry. Apply the glue to the device and attach the cable being careful to have the angled cut on the cable face the housing for maximum exposure of the fiber optics. DO NOT get any glue on the cut end of the cable. Let the glue dry 24 hours before using the device underwater. "Mighty Bond" glue was used here. It is the Philippine equivalent of Super Glue.
FINISHED PRODUCT
The fiber optic cable lines up with the center area of the camera's strobe.
The overhang area of the device helps block the camera's strobe. If you cut the device shorter the camera's strobe will likely be in a portion of the photo and show as a "hot spot".
FOOTNOTE
Ideally you want the camera's strobe to be set to its lowest intensity to save battery life but still be able to fire your slave strobe. The Canon G10 has three strobe levels of intensity in 1/3 increments.  I use a Sea & Sea YS-27DX strobe and found that the lowest camera strobe setting did not consistently fire my 27DX underwater with this device so I set it to the mid-range setting for consistency. Be sure to test your camera and slave strobe underwater to determine what strength you need to set your camera's strobe at.