Canon WP-DC33 Underwater Housing for Canon PowerShot SD940IS Digital Camera For small underwater subjects, choose the Macro Mode. Move to within minimum focusing distance of your subject and depress the shutter button halfway. The first thing to master with wide-angle shots is keeping the water color blue. Panorama - First, select the Stitch Assist Mode on your PowerShot digital camera. Shoot a series of overlapping images. You can also use your Canon Waterproof Case on land in environments where snow, sand, excess humidity or dust could lead to damage. Follow instructions for maintenance tips to optimize housing performance