Certified Professional Photographer (CPP) Practice Exam

What is the primary result of using a polarizing filter at a 35º-60º angle to the reflecting surface?

1. Increase brightness

2. Reduce glare

3. Enhance contrast

4. Soften image sharpness

The correct answer is: Reduce glare

When using a polarizing filter at a 35º-60º angle to a reflecting surface, the primary result is a reduction in glare. This is because polarizing filters are designed to block certain light waves, particularly those that are reflected off non-metallic surfaces like water or glass. At the specified angle, the polarizing filter effectively removes this polarized light, reducing unwanted reflections and allowing for clearer and more vibrant images. The reduction of glare not only improves the visibility of the subject matter but also enhances the overall quality of the photograph by providing more accurate colors and details that might otherwise be obscured by harsh reflections. This technique is especially useful in landscape photography, where water surfaces and skies may create significant glare. The other options relate to effects that may occur but are not the primary focus of the use of a polarizing filter at this angle. While increasing brightness and enhancing contrast can occur indirectly through the improved clarity of the image, the main purpose of the filter in this context is to mitigate the reflective glare. Similarly, softening image sharpness is not a result of using a polarizing filter; the filter is instead intended to optimize sharpness by improving visibility of the subject.