They are physical screw on filters that go on my lens. I have different passthrough filters for what im looking for, IR720, IR760, IR850, IR950, UV403 is what I have for my 52mm lens. I try to refenece in my photos what wavelength I am isolating.
Without these filters, in the bright daylight my pictures would be overexposed, even at 200 iso, and the, aperture completely open and fastest shutter speed due to my full spectrum modification. So I use filters to get these amazing pictures.. Think of it like Riddick's eyes, you know Vin Diesel, his eyes are really sensitive so he wears shades all the time :-P
Very artistic