Clear Research Grade Filter for UVBRI set, 1.25". Clear filters transmit all wavelengths from the UV to the far IR; they are clear, high-precision, optical windows designed to transmit all wavelengths of light without having to refocus when switching back to a color filter.

This is a clear infra-red blocking filter in the commonly used 1.25" size. Used when taking RGB images to remove IR for better color balance.

Neutral Density (ND 2, 1.0%T) 1.25", mounted. All of our astronomical filters have IR blocking "built-in" so IR light does not contaminate today's sensitive CCD detectors. When you use filters from Custom Scientific, you do not need any additional IR blocker filters.

All of our astronomical filters have IR blocking "built-in" so IR light does not contaminate today's sensitive CCD detectors.

Your choice: U, B, V, R, or I, 1.25" Research Grade filter, mounted. Research Grade filters have surface flatness of Lambda/4 per inch and 1 arc minute parallelism. Price is for each filter. Please specify when ordering.

Clear Standard Grade Filter for UVBRI set, 50mm. Clear filters transmit all wavelengths from the UV to the far IR; they are clear, high-precision, optical windows designed to transmit all wavelengths of light without having to refocus when switching back to a color filter.

Neutral Density (ND 2, 1.0%T) 50mm, unmounted. All of our astronomical filters have IR blocking "built-in" so IR light does not contaminate today's sensitive CCD detectors.

For nighttime use only. NOT for solar viewing. Hydrogen-alpha 10nm passband. This filter is designed for non-solar imaging, and is used to image deep-sky objects that emit in the h-alpha passband. It is too wide for solar-prominence viewing, but is ideal for deep sky. Filter has Anti Reflective Coatings.

Your choice: U, B, V, R, or I, 50mm Standard Grade filter, mounted. Price is for each filter. Please specify when ordering.

Used in conjunction with the OIII filter for subtraction of green background. Filter has Anti Reflective Coatings.

Used for subtraction of blue background. All of our astronomical filters have IR blocking "built-in" so IR light does not contaminate today's sensitive CCD detectors. When you use filters from Custom Scientific, you do not need any additional IR blocker filters. One exception is in the thickness-matched Clear filters which transmit all wavelengths from the UV to the far IR; they are clear, high-precision, optical windows designed to transmit all wavelengths of light without having to refocus when switching back to a color filter. Filter has Anti Reflective Coatings.

Neutral Density (ND 2, 1.0%T) 50mm, unmounted. All of our astronomical filters have IR blocking "built-in" so IR light does not contaminate today's sensitive CCD detectors.

A 4.5nm passband filter for imaging deep sky objects in the light of hyrogen-beta emissions. This filter passes the h-beta emission line while blocking other wavelengths. Filter has Anti Reflective Coatings.

Sulfur II 672.4/4.5nm, 1.25" with Anti Reflective Coatings.

A 4.5nm passband filter for imaging emission nebula. This filter passes the Oxygen III emission line while blocking other wavelengths. Filter has Anti Reflective Coatings.

Red, Green, Blue, and Clear filters in the most commonly used format: 1.25".

Hydrogen-alpha 4.5nm passband. This filter is designed for non-solar imaging, and is used to image deep-sky objects that emit in the h-alpha passband. It is too wide for solar-prominence viewing, but is ideal for deep sky. Filter has Anti-Reflective Coatings.

For nighttime use only. NOT for solar viewing. Hydrogen-alpha 10nm passband. This filter is designed for non-solar imaging, and is used to image deep-sky objects that emit in the h-alpha passband. It is too wide for solar-prominence viewing, but is ideal for deep sky. Filter has Anti Reflective Coatings. NOTE: 1.25" mounted illustrated.

H-Alpha 656.3/4.5 50mm with anti-reflection coatings. For nighttime use only. NOT for solar viewing. Hydrogen-alpha 4.5nm passband. This filter is designed for non-solar imaging, and is used to image deep-sky objects that emit in the h-alpha passband. It is too wide for solar-prominence viewing, but is ideal for deep sky.

Methane 889/18nm 1.25" filter with Anti Reflective Coatings. All of our astronomical filters have IR blocking "built-in" so IR light does not contaminate today's sensitive CCD detectors.