Just before leaving to North Sulawesi and in the process of packing I realised I had not completed the tweak of my GoPro Hero2 Set up.
I do not use the GoPro for video but for time lapse however the modification that I will present here is valid for both video and stills or time lapse.
Some users of the PolarPro filter have noticed that when you point the camera to the sunball or on a very bright day there is quite a bit of flare with this filter in the image corners.
Flare occurs when stray light enters the frame and reduces contrast giving a result a picture with washed out colours.
Flare is more relevant to wide angle and is usually reduced with lens hoods however our GoPro does not have anything like that and due to the large field of view probably it is better to be so otherwise the hood would be visible.
So what can we do to improve our polarpro filter and why does it flare more than others in the first place?
The PolarPro is the lowest price push up filter for the gopro and the reason is that its build is very simple. All other filters will have a dark rubber ring on the edge that has the dual effect to secure the filter to the housing and eliminate the stray light that may enter from the side. The polarpro is one single piece of acrylic and does not have this ring around the lens.
So let’s build one cheaply all you need is genuine gaffer tape, to make it look better I suggest black matt gaffer.
Pull enough length to cover the whole external ring of the polar pro filter and lay it on it to go from the edge of the front side back to the where the lateral panel ends. Once you have measured the approximate length make note of the width and then remove the gaffer. Pull the tape so that it rips at the width required and then tape the exterior making sure the smooth part is on the front side. Then create another strip a bit longer for the inner part. Make sure it is going straight and with no bubble and then once you get to the opening for the button come outside and overlap the exterior ring.
Once finished it should look like this

This is the other side you notice the part we ripped of the gaffer is on the outer side

Gaffer type does not mark and will stay there for a good number of dives. I am going to test this and see how long it goes but I expect more than 20 dives before it falls apart.
What you have seen here can be done for the Hero3 filters and it is actually simpler as the filter has no button opening
There has been a new Mako product coming at the low cost end and that one has a rubber ring so I would recommend trying it if you don’t have a filter already