# Neutral density filter demonstration

- By: Robert Emperley from Strasbourg, Alsace, France
- Date: 2010-05-15
- Classification: Photograph
- Credit line: silver falls 21 Uploaded by NotFromUtrecht
- Museum: [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Neutral_density_filter_demonstration.jpg)
- Rights: [CC BY-SA 2.0](https://creativecommons.org/licenses/by-sa/2.0)
- Picture: https://invisiblenetwork.ai/thumbs/commons/thumb/5/5e/Neutral_density_filter_demonstration.jpg/1920px-Neutral_density_filter_demonstration.jpg
- Who can see it: Teens profiles and older (museums give no ratings; placed by Invisible Network from the museum's own words)

Hoya HMC Pro1 Neutral Density (ND) ND4 filter used to increase exposure time and accentuate water flow in daylight. This filter reduces the amount of light by 2 stops. Picture taken while hiking along the Silver River and the Silver Falls of Upper Peninsula, Michigan.