Thanks to Gareth off the forum for the DX lenses to test
DX lens UV400 tests.
I read the arguments about the cheap DX specs and offered to test the specs to see what UV protection if any they offered.
As these are oakley based specs I followed ANSI Z80.3-2001 which states the following:
The U.S. standard is ANSI Z80.3-2001, which includes three transmittance categories. According to the ANSI Z80.3-2001 standard, the lens should have a UVB (280 to 315 nm) transmittance of no more than one per cent and a UVA (315 to 380 nm) transmittance of no more than 0.3 times the visual light transmittance. The ANSI Z87.1-2003 standard includes requirements for basic impact and high impact protection. In the basic impact test, a 1 in (2.54 cm) steel ball is dropped on the lens from a height of 50 in (127 cm). In the high velocity test, a 1/4 in (6.35 mm) steel ball is shot at the lens at 150 ft/s (45.72 m/s). To pass both tests, no part of the lens may touch the eye.
I didn't do the steel ball shot part of the test as I don't have the equipment, I tried to get hold of a set of oakley's to do a direct comparison test but was unable to get any - It's not that sunny here in ireland.
Glasses tested were:
Decathlon Ti polarised fishing glasses.
Bolle prescription safety specs.
High end fashion prescription specs.
2x DX lenses (1x mirrored finish, 1x dark finish).
The results were interesting.
Decathlon Ti polarised fishing glasses - Met Part A (just), failed Part B.
Bolle prescription safety specs. Met Part A and B.
High end fashion prescription specs. Met Part A and B.
DX lenses 1x mirrored finish. Met Part A and B, had best protection of all specs tested (step change extended out to 430nm @ ~38% absorbance).
DX lenses 1x dark finish Met Part A and B.
All specs displayed very similar profiles, with a sharp drop in absorbance at ~405nm, there was a step for the mirrored specs as mentioned above. The polarised specs was an expected fail due to the nature of the lens, when I bought them they were not advertised as uv400.