I reduced this value for use on the Nintendo Switch screen as the dark screen and Nintendo's zero effort to control reflections make it nearly impossible to use outdoors. The film doesn't help thinking as much as I had hoped. This appears to increase the contrast and clarity of the image (you can see more black under the film in the photo), but it does very little to reduce reflection (see the circled portion of the photo). While the improvement in image sharpness is good, the upside seems to be the anti-glare quality, which is very scarce.
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