Today’s topic…. DOME PORT housings!
So firstly, for those not too sure what a DOME PORT is, its a standard GoPro waterproof housing with a big bowl in front of it, that allows you to get much better shots that have a body of water in the lower half of the shot, this kind of shot is known as semi submerged, under/ over or 50/50. If you try to get this kind of shot with the standard housing, the water line is so close to the lens sensor, that it dominates the shot, and is wildly out of focus. You will also have water distortion issues, where the water slightly magnifies everything within. Not mention if theres any slight ripples in the water, thats a very hard target to line up! See image below!
So what do they look like exactly? There are quite a few variations, but all do follow the same basic design of clear perspex dome out front, backing plate, then waterproof housing out back. And vary in price from around USD$50 right upto around USD$400. Now the cheap domes have one thing in common, and is their biggest flaw, their dome is a bad shape! See picture below!
If you look at the actual DOME section, the clear plastic bowl, you will see it looks like someone got a perfect bubble, cut it in half and used that as the bowl. Whats the harm in that right? The problem with this shape is, nearly half of that bowl, when semi submerged, will reflect sunlight towards the camera lens and also illuminate the backing plate, despite it being matt black. See pic below!
And as you can see from this shot, the glare on the left and right totally ruins the it. The amount of glare will also vary, depending on your position to the sun, how submerged the dome is, and the domes vertical angle. So while you might think, “USD$50 dome, awesome!!!”, be prepared to have shots with this issue. Personally, I’m amazed DOMES with this bowl shape are still being sold, when the best option is a very simple redesign issue, but the manufacturers unwillingness to change to provide a better product, clearly shows they are NOT GoPro users them selves, so really, are they worthy of your hard earned dollars? If they dont care about providing a good product?
So examples of the good shape domes I hear you asking for? See below!
This is much less than half a bubble, so we call this shape a ‘1/3 sphere’. If you compare roughly where the glare from the ‘1/2 sphere’ starts, you will notice that its about where the bowl meets the backing plate on the 1/3 sphere, making the ‘dome glare’ issue non existent. You can still pick these DOME housings up quite cheaply, but keep in mind, they are a very basic unit. General rule of thumb is, all domes under USD$80 will be quite basic models with no LCD viewing window or power button access, meaning you need to have your cam switched on, AND in the desired mode before putting it in the housing, making it quite limited, and makes you blind in terms of being able to see shot count and power level (unless you have rear LCD).
The next range up is between USD$80 to $130, and will offer an additional feature, being either power button access built into the DOME backing plate, or LCD viewing window. Both features are extremely handy, knowing where your shot count and power level is at, is a very handy thing to know, but not having power button access means still having to be switched on and in mode, or you have to open the housing which potentially allows for some moisture to enter the housing, and this creates additional issues. On the flip side, having power button access means you can turn your cam on when your at your shoot point, and can easily scroll between modes, but how do you know how many shots have been taken, or what the battery level is if you cant see it (unless you have the H4S!). A potentially tough decision to make
And one more thing to cover, cleaning, see below…
Cleaning your dome…
Unlike waterproof housing lenses, which are flat glass, domes are plastic, so never use any cleaning products that contain alcohol or any other kind of thinning agent. These will degrade the surface of the plastic, which will impact image clarity. So with this in mind, NEVER use RainX to avoid water spots either! To keep your dome clean, just give it a good wipe with water and soft lens cloth.
And how to avoid water sports? This will sound strange if you’ve never heard of this trick before, but countless surfing photographers swear by it, and so do we. Lick it! Thats right, lick that dome, and ensure you get good even coverage. This is not some strange joke, it really does work. Cover the entire dome, then a quick dunk and your ready to go. The footage in the video below came out so well with no water spots on the dome because we used this method prior to filming. You’ll be surprised how well it works!
And for an interesting comparison between GoPro and a Chinese brand counterpart, check the video below.