iTint calculates a relative Visible Light Transmission (VLT) percentage of an transparent object. The most practical use is for automotive glass, but can also be used for sunglasses, swim goggles, and camera filters. Yes, this app can even do windows! Measure and record your results for future reference. Shopping for a pair of sunglasses? Why not record the VLT of each pair instead of just guessing the the tint darkness.
As an added bonus, the U.S. state tint laws for automotive glass are included (front side, back side, and rear only). Avoid getting cited for illegal tint darkness. Avoid getting a ticket just because of officer discretion. Great tool for window tint installers.
How does this work?
Your iPhone/iPod Touch is split in two sections, where the bottom half is bright white, and the top half is adjustable. Position the bright white section to shine though the glass (only touch the glass with the bottom edge. Do not allow the screen to lie flat on the glass), and the top section above the edge of the glass. Adjust the top section brightness to match the brightness of the bottom. This will work with all generations of iPhone and iPod Touch, regardless of the current brightness setting, or if you have a protective cover on your device. The VLT percentage is displayed in the center top. It's that simple.
Because not everyone can tell the difference between light and dark the same, there are helper side bars that step a different percentage to aid measurement. Use in landscape mode for even more transition steps. Use the pinch gesture to increase or decrease the step value.
You can practice matching random levels to perfect your technique, or if you want to try your skill at matching before purchase use 'iTint Lite'.
Some default calibration points are initially set up to start, but you can greatly improve accuracy, by calibrating with a set of known reference tints. You can purchase a set at this web site: http://www.eplastics.com/Plastic/Samples/SAMPLE-ACRYBRONZE-GRAY
Check out my web site for more hints on how to use this tool effectively. Click on the iTint support link below to get the latest information and FAQ.
This tool is not certified for accuracy since the calibration (your eye) is subjective. To properly measure VLT% the entire visible light spectrum must be used, this app only measures one wavelength. The screen brightness curve varies on different devices. Your results may vary from the actual VLT%.
All information in the U.S. States tint laws are from the International Window Film Association (IWFA), and are subject to change. Please consult your local state laws for detailed information. The U.S. Department of Transportation specifies a minimum of 70% VLT on windshields. No states allow tinting of the front windshield, except for parts of the top. The information on the front windshield is not included in this app.