From what I see, you have 3 solutions:
- 1) ordering from EDR http://www.edr-auto.fr/shop/ambarella/66-g90-polarizer-filter-pro-support.html and pay 30 € in France (for outside, probably it'll cost more because of transport): 30 €++
- 2) designing your own adapter using SolidWorks, Catia or, why not, the free Google Sketchup. Then, if you don't have a 3D printer, find someone in Poland to print your adapter. Also, find a CPL filter. All this story may cost less than 30 €.
- 3) use similar methods as other users have used.
Some time ago I searched for a lens protection (to avoid lens scratches and pushing the lenses inside). I found the perfect cap from a deo spray whose diameter was slightly increased using a hair-dryer and a cap from a WD40. You could also use a hot air gun or hot water. Don't forget to pierce the cap to make sure no air is trapped inside.
In order to connect the CPL on the dashcam you'll need some adapters. I chose the 52mm CPL to make sure there were no problems due to wide angle lens.
I bought 2 metal adapters 30 to 52 mm, paying 1.60 €/item (shipping included); Today they cost 3.42 € + 1.40€ (shipping) .
I'll also buy two others adapters 34 to 52 mm Today one costs 1.32 €.
This is how the 30 to 52 mm step ring fits on the cap:
Next is to cut the part marked in red and screw in the adapter. I could also glue the cap and the adapter together (I don't mind).
The cap is easy to remove and put it back, the only problem is: I don't have any other cap available ...when I had, I throw them away, so now I'll have to buy another deo spray
As you can see the total cost is quite low and the result will not be so bad. You can also sandpaper the cap and paint it black, etc. With rest on the money you can buy CPL and UV filters on your choice.
