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OPTICAL FILTERS FOR ASTRONOMY APPLICATIONS
Astrophotography uses spectral imaging to measure diverse properties of astronomical objects including molecular composition, ionisation state, redshift, and temperature. Chroma Technology manufactures the highest quality, narrow-band spectral line filters for detecting ionised sulfur, oxygen, and H-alpha or H-beta and other elements.
Stargazing unveiled with sputtered coatings for clarity
Tadpoles Nebula
Jaspal Chadha
The large dark nebula that makes up this "gaping mouth" is a molecular cloud made up predominantly of molecular hydrogen, but also dust and other gases. New generations of solar systems are being forged within its cold interior. Once these young stars’ fusion engines switch on, they will irradiate their surroundings–heating up, ionising and eroding away the remaining dark material from which they formed.
NGC 281A
LOCATION : London, UK
DATE : September—October 2015
TELESCOPE : Skywatcher Esprit 100ED
(Taken during High moon transit)
CCD : QHY9S MONO CCD
Ha 1200s x 18; SII 1200s x 10; OIII 1200s x 10
Mount iOptron CEM60
FILTERS : Chroma Technology 3nm spectral line filters: H-alpha, OIII and SII
Originally the whole Pac-Man nebula would have been one large dark molecular cloud. The stars that formed early on at its centre have progressively hollowed out the centre of the nebula. The gas in and around this central region is ionised by the copious UV radiation emitted by the central open star cluster (IC 1490), causing it to glow and provide the light by which this narrowband image was taken.
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Running Man Nebula
The Orion Nebula is the brightest nebula visible from the Northern Hemisphere. It’s located in the sword of Orion, just below the belt, and lies 1,344 lightyears from Earth. This two-panel mosaic was photographed under northern skies in Valencia. Integration four nights; Chroma Filter LRGB filters; AG14 Newtonian astrograph; camera: Starlight Xpress Trius SX-814
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Soul Nebula
Astrophotography Filters And Filter Sets
Durable sputtered coatings
Thickness: 3.0mm
Filters designed for use with CCD and for f/4 0 or slower
Transmitted wavefront better than 0 25 waves/inch
LRGB/HALRGB FILTERS AND FILTER SETS
Durable sputtered coatings
Thickness: 3 0mm
Filters designed for use with CCD and for f/4 0 or slower
Transmitted wavefront better than 0.25 waves/inch
H-alpha filters are not for solar observation. Optical filters are angle sensitive and shift to the blue with fast focal ratios. 3nm filters shift enough to compromise transmission at the wavelength line of interest. Chroma has made a set of Ha, OIII and SII 3nm that are optimised for F/3 beams by moving the centre wavelength slightly into the red so they will shift to the blue when used in an F/3 beam, thus maximising transmission at the nominal wavelength. For beams faster than F/3, we recommend using 5nmwide or wider bands.
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Horsehead Nebula
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Photometry
Bessell Filters for Standard Photometric Surveys
Sloan ugriz Filters for Standard Photometric Surveys
Want to learn more about Chroma and your astrophotography/photometry application? Contact our Technical Director, Dr. Shayz Ikram by email or call (01372) 378822.
