Filters


Filter FWHM (Å) CWL (Å) Telescope Instrument Plot Data Comments
kp809 67.00 6488.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters kp809 kp809 Minor edge separation
H-alpha +18nm 83.00 6746.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters H-alpha +18nm H-alpha +18nm set1
HST f814w 2509.00 8289.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters HST f814w HST f814w
Hale-Bopp UVC 78.00 3448.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters
Stromgren v 159.00 4103.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Stromgren v Stromgren v
H-beta wide 173.00 4871.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters H-beta wide H-beta wide
HST f555w 1597.00 5305.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters HST f555w HST f555w
Harris set R- spare 1515.00 6488.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Harris set R- spare Harris set R- spare
H-alpha +22nm 78.00 6786.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters H-alpha +22nm H-alpha +22nm set1
SDSS z' 0.00 8325.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters SDSS z' SDSS z' Sloan Digital Sky Survey set
Gunn u 508.00 3463.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Gunn u Gunn u
Hale-Bopp CO 56.00 4265.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters
HBeta 63.00 4871.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters HBeta HBeta Replaces 804
kp1443 265.00 5311.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters kp1443 kp1443 Spatially var. fringing, replaced by KP1582 - Not available
Osmer/Green R 871.00 6517.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Osmer/Green R Osmer/Green R
Todd Boroson filter 2 798.00 6819.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Todd Boroson filter 2 Todd Boroson filter 2
Gunn z 0.00 8495.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Gunn z Gunn z RG850
Gunn u KPNO 2.1-meter Telescope KPNO 4-Inch Filters Gunn u
BG12 1015.00 4299.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters BG12 BG12 1mm + GG385 2mm
H-beta narrow 25.00 4876.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters H-beta narrow H-beta narrow
Harris V 1059.00 5397.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Harris V Harris V 2.1 meter set
Gunn r 803.00 6527.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Gunn r Gunn r B1/K1
H-alpha +27nm 75.00 6832.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters H-alpha +27nm H-alpha +27nm set1
Mike Irvin's Z 0.00 8525.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Mike Irvin's Z Mike Irvin's Z
SDSS u' 628.00 3513.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters SDSS u' SDSS u' Sloan Digital Sky Survey set
Harris B 1069.00 4312.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Harris B Harris B new 7/98
Washington c48 200.00 4898.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Washington c48 Washington c48 Washington set, property of Doug Welch, McMaster Univ
Harris set V- spare 1015.00 5417.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Harris set V- spare Harris set V- spare
Harris R 1559.00 6531.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Harris R Harris R Not available
H-alpha +31nm 76.00 6877.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters H-alpha +31nm H-alpha +31nm set1
Osmer/Green 8600 690.00 8642.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Osmer/Green 8600 Osmer/Green 8600 Green 8600
Stromgren u 278.00 3537.00 KPNO 2.1-meter Telescope KPNO 4-Inch Filters Stromgren u Stromgren u UG11+WG345
I Nearly-Mould k1005 Nicholas U. Mayall 4-meter Telescope Mosaic I Nearly-Mould k1005
ha16 H-alpha+16nm k1013 Nicholas U. Mayall 4-meter Telescope Mosaic ha16 H-alpha+16nm k1013 ha16 H-alpha+16nm k1013 Below is a plot of the transmission of this filter when used at telescopes with differing focal ratios and central obscurations; the KPNO 4m (f/3.1), the CTIO 4m (f/2.9), and the WIYN 0.9m (f/7.9). At the KPNO 4m f/3.1 the properties of this filter are: CWL=6705A, FWHM=81A, PEAK TRANSMISSION=91.7%.
wrc4 WR CIV k1024 41.79 5828.71 Nicholas U. Mayall 4-meter Telescope Mosaic wrc4 WR CIV k1024 wrc4 WR CIV k1024 Note that there is a shift in central wavelength when placed in different f/ratio beams. At the KPNO 4meter f/3.1 beam this corresponds to a shift of approximately 12 Angstroms bluer; at the CTIO 4meter f/2.9 this corresponds to a shift of approximately 15 Angstroms bluer; at the WIYN 0.9m f/7.9 this corresponds to a shift of approximately 5 Angstroms bluer. See the plot at the bottom of the page.
918R 918R_v1 k1028 Nicholas U. Mayall 4-meter Telescope Mosaic 918R 918R_v1 k1028 918R 918R_v1 k1028
Ud Dey custom U k1045 329.76 3485.23 Nicholas U. Mayall 4-meter Telescope Mosaic Ud Dey custom U k1045 Ud Dey custom U k1045 Note that there is a shift in central wavelength when placed in different f/ratio beams. At the KPNO 4meter f/3.1 beam this corresponds to a shift of approximately 12 Angstroms bluer; at the CTIO 4meter f/2.9 this corresponds to a shift of approximately 15 Angstroms bluer; at the WIYN 0.9m f/7.9 this corresponds to a shift of approximately 5 Angstroms bluer.
454 BATC k1054 ** Nicholas U. Mayall 4-meter Telescope Mosaic 454 BATC k1054 ** 454 BATC k1054 ** Note that there is a shift in central wavelength when placed in different f/ratio beams. At the KPNO 4meter f/3.1 beam this corresponds to a shift of approximately 12 Angstroms bluer; at the CTIO 4meter f/2.9 this corresponds to a shift of approximately 15 Angstroms bluer; at the WIYN 0.9m f/7.9 this corresponds to a shift of approximately 5 Angstroms bluer.
802 BATC k1062 ** Nicholas U. Mayall 4-meter Telescope Mosaic 802 BATC k1062 ** 802 BATC k1062 ** Note that there is a shift in central wavelength when placed in different f/ratio beams. At the KPNO 4meter f/3.1 beam this corresponds to a shift of approximately 12 Angstroms bluer; at the CTIO 4meter f/2.9 this corresponds to a shift of approximately 15 Angstroms bluer; at the WIYN 0.9m f/7.9 this corresponds to a shift of approximately 5 Angstroms bluer.
ha H-alpha c6009 80.00 6563.00 Nicholas U. Mayall 4-meter Telescope Mosaic ha H-alpha c6009 ha H-alpha c6009 Note: The central wavelength of CTIO Mosaic narrow band filters (actually all filters, but is very significant for narrow band filters) is shifted ~15A to the BLUE in the f/2.87 beam of the Blanco 4m + PFADC corrector as compared to the transmission measured in parallel light. The central wavelength quoted below is nominally for when the filter is used at PF, with the ~15A shift included. Furthermore, the filter transmission curve presented below shows the simulated filter transmission curve for the Blanco 4m + PFADC f/2.87 beam.
C Washington k1006 1034.00 3860.00 Nicholas U. Mayall 4-meter Telescope Mosaic C Washington k1006 C Washington k1006 Note that there is a shift in central wavelength when placed in different f/ratio beams. At the KPNO 4meter f/3.1 beam this corresponds to a shift of approximately 12 Angstroms bluer; at the CTIO 4meter f/2.9 this corresponds to a shift of approximately 15 Angstroms bluer; at the WIYN 0.9m f/7.9 this corresponds to a shift of approximately 5 Angstroms bluer. See the plot at the bottom of the page.
O3 OIII N2 k1014 * 55.55 5024.90 Nicholas U. Mayall 4-meter Telescope Mosaic O3 OIII N2 k1014 * O3 OIII N2 k1014 * Note that there is a shift in central wavelength when placed in different f/ratio beams. At the KPNO 4meter f/3.1 beam this corresponds to a shift of approximately 12 Angstroms bluer; at the CTIO 4meter f/2.9 this corresponds to a shift of approximately 15 Angstroms bluer; at the WIYN 0.9m f/7.9 this corresponds to a shift of approximately 5 Angstroms bluer. See the plot at the bottom of the page.
wrc4 WR CIV k1024 Nicholas U. Mayall 4-meter Telescope Mosaic wrc4 WR CIV k1024 wrc4 WR CIV k1024 Below is a plot of this filter as simulated in different f/ratio beams. At the KPNO 4m f/3.1 the properties of this filter are: CWL=5819A FWHM=42.17A PEAK TRANSMISSION=71.36%
918R 918R_v1 k1028 Nicholas U. Mayall 4-meter Telescope Mosaic 918R 918R_v1 k1028
Ud Dey custom U k1045 Nicholas U. Mayall 4-meter Telescope Mosaic Ud Dey custom U k1045 Ud Dey custom U k1045
454 BATC k1054 ** Nicholas U. Mayall 4-meter Telescope Mosaic 454 BATC k1054 ** 454 BATC k1054 **
802 BATC k1062 ** Nicholas U. Mayall 4-meter Telescope Mosaic 802 BATC k1062 ** 802 BATC k1062 **
ha8 H-alpha+8nm c6011 80.00 6650.00 Nicholas U. Mayall 4-meter Telescope Mosaic ha8 H-alpha+8nm c6011 ha8 H-alpha+8nm c6011 Note: The central wavelength of CTIO Mosaic narrow band filters (actually all filters, but is very significant for narrow band filters) is shifted ~15A to the BLUE in the f/2.87 beam of the Blanco 4m + PFADC corrector as compared to the transmission measured in parallel light. The central wavelength quoted below is nominally for when the filter is used at PF, with the ~15A shift included. Furthermore, the filter transmission curve presented below shows the simulated filter transmission curve for the Blanco 4m + PFADC f/2.87 beam.
U k1001 630.71 3552.00 Nicholas U. Mayall 4-meter Telescope Mosaic U k1001 U k1001 Note that there is a shift in central wavelength when placed in different f/ratio beams. At the KPNO 4meter f/3.1 beam this corresponds to a shift of approximately 12 Angstroms bluer; at the CTIO 4meter f/2.9 this corresponds to a shift of approximately 15 Angstroms bluer; at the WIYN 0.9m f/7.9 this corresponds to a shift of approximately 5 Angstroms bluer.
C Washington k1006 Nicholas U. Mayall 4-meter Telescope Mosaic C Washington k1006 C Washington k1006 Below is a plot of the transmission of this filter when used at telescopes with differing focal ratios and central obscurations; the KPNO 4m (f/3.1), the CTIO 4m (f/2.9), and the WIYN 0.9m (f/7.9). At the KPNO 4m f/3.1 the properties of this filter are: CWL=3892A, FWHM=1030A, PEAK TRANSMISSION=77.4%.