Well, it was overcast/rainy today whether that'd make any difference (shouldn't, if comparing with a sample)
It is not a factory tint - it was done December 2023, i know that the tint shop checked the glass before tinting (which came out to zero) then I asked for minimum legal VLT of 35%. I don't think they checked the VLT afterwards.
The AA testing station I went to where another car failed for too dark tint, they said it was 13% (i knew it was too dark anyway so that's fine), obviously they measured VLT to give me the figure, rather than blanket "too dark"
I'll go to the tint shop and get a piece of paper with a number on it and hope for the best, but I'm just curious where the onus lies.
VIRM says this, so I assume that you'll have to measure it to pass/fail it.
Note 8
A tolerance of 5% is permitted for the visible light transmittance (VLT) reading, to compensate for variations in tint film and light meters.