water will adhere to the port surface in varying degrees forming rivulets and beads on the dome surface. In addition to being annoying, it will also have a negative impact on the surface subject. A rivulet or drop will, on its own, act as a mini lens on the surface of the port and cause image distortion. I find that glass tends to have less surface tension than does acrylic, meaning that water will “sheet” more cleanly off the glass surface better leaving fewer rivulets and droplets than acrylic. Through trial and error, I have found an effective technique to minimize the offensive water issues on the dome. The technique employs dunking the entire dome underwater and shooting the camera on Continuous Trigger Release Priority while slowing lifting the housing from the water. As you do this, a thin layer of water remains on the entire surface of the dome for a brief instant due to surface tension before sheeting off under gravity. Because this water layer is uniform, it does not impart image distortion on the above surface portion of the image. By shooting continuous release mode as you slowly lift the housing from the water, you will likely capture at least an image or two in the burst that will have both the UW and PHOTO PRO continued
surface subject within the scene. While splits can be done in deep water, the inherent weight of the housing/dome port system lends it to be best used in water shallow enough to stand. After shooting a burst of shots, check your work. I typically shoot a series of shots at a given group of settings and camera angles, then check the LCD for both image quality and histogram clipping. Generally, histogram clipping is rarely an issue. However, camera housing angle is often something I need to correct. As I am generally above the camera, my view of the camera angle may not be perpendicular to the subject, resulting in either too much UW or surface subject. So I use the image set in the LCD and adjust ac- cordingly. Finally, when I think I have a set of images that appear to be winners, I will select them individually in the LCD and blow them up to check for sharpness of both the UW and surface subjects. I’ve learned the hard way that failing to
check image sharpness across the scene is a guarantee I’ll end up with more losers than winners when enlarged on the computer.
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