Cover image by fujikko
For creators, choosing the right technology to enhance photo quality is crucial. Among these choices, whether or not to use a low-pass filter can significantly affect the quality of photos.
A low-pass filter is an optical filter installed on a camera sensor, primarily serving to prevent moiré effects (the appearance of unnatural stripes or waves when photographing fine patterns). For example, it can prevent unwanted stripes from appearing when photographing a TV screen.
While a low-pass filter can reduce visual noise in certain situations, it may also impact the sharpness of photos. This article clearly explains the advantages and disadvantages of low-pass filters.
Image by ぶらいあんと
Advantages and Disadvantages of Having a Low-Pass Filter
Advantage: Reduction of Moiré Effects
The greatest advantage of a low-pass filter is its ability to effectively prevent moiré effects. Moiré refers to unnatural wave patterns that occur when fine patterns overlap. It can occur, for example, when photographing a finely checked shirt or the lattice pattern of a building. The low-pass filter reduces such phenomena by slightly blurring the image's sharpness, thus reducing visual noise.
Disadvantage: Decrease in Resolution
Using a low-pass filter can sometimes decrease the perceived resolution of images. In landscape or portrait photography, where detailed expression is desired, the filter's effect of reducing sharpness can be a drawback. While the blurring effect of the filter can be beneficial when detail clarity is not crucial, it can be a disadvantage in situations where high-resolution images are required.
Image by 中嶋 凌 / Nakajima Ryo
When You're Unsure Which to Choose
The key is to choose what suits your shooting purpose and style.
If you mainly shoot landscapes or portraits, choosing a camera without a low-pass filter can result in sharper photos. On the other hand, if you frequently photograph subjects with fine patterns, a camera with a low-pass filter is suitable to reduce the risk of moiré. In any case, selecting the best option according to your style is crucial for taking better photos.
