Optical Filter Guides

A useful filter choice starts with understanding the light you want to keep. These practical guides help you read the curves, compare filter types and work through the details of your application.

Not sure where to begin?

Start with the selection guide, then learn what the transmission chart can tell you.

Find your filter type →Learn to read a chart →

Explore the guides

Have a particular setup in mind? Tell us what you are trying to achieve, and we can discuss a suitable starting design.

Optical Filter Guides

Neutral Density Filters: How Much Light Reducti...

Turn “too bright” into a useful attenuation target, then check the filter spectrum, mounting and power conditions.

Neutral Density Filters: How Much Light Reducti...

Turn “too bright” into a useful attenuation target, then check the filter spectrum, mounting and power conditions.

Hot Mirror vs. Cold Mirror: Which Light Should ...

Draw the two light paths before choosing the mirror. The names refer to spectral behavior, not the temperature of the glass.

Hot Mirror vs. Cold Mirror: Which Light Should ...

Draw the two light paths before choosing the mirror. The names refer to spectral behavior, not the temperature of the glass.

Longpass, Shortpass or Bandpass: Which One Fits...

One spectral boundary or two? Choose the filter family by deciding which wavelengths you want to retain.

Longpass, Shortpass or Bandpass: Which One Fits...

One spectral boundary or two? Choose the filter family by deciding which wavelengths you want to retain.

Choosing a Bandpass Filter for Your LED and Camera

Matching the wavelength on the label is only the beginning. Learn how source bandwidth, background and working angle affect the choice.

Choosing a Bandpass Filter for Your LED and Camera

Matching the wavelength on the label is only the beginning. Learn how source bandwidth, background and working angle affect the choice.

How to Read an Optical Filter Transmission Chart

A guided look at a measured KUPO spectrum: find the useful band, read the values and understand the limits of the plot.

How to Read an Optical Filter Transmission Chart

A guided look at a measured KUPO spectrum: find the useful band, read the values and understand the limits of the plot.

Which Optical Filter Do I Need? A Practical Sel...

Start with the change you need to make to your light. This guide helps you narrow the filter family before comparing individual products.

Which Optical Filter Do I Need? A Practical Sel...

Start with the change you need to make to your light. This guide helps you narrow the filter family before comparing individual products.