Filters


Filter FWHM (Å) CWL (Å) Telescope Instrument Plot Data Comments
RG-645 0.00 0.00 Nicholas U. Mayall 4-meter Telescope RC Spectrograph RG-645 RG-645 Sharp-Cut Filter. Cutoff filter: no transmission peak, FWHM is undefined.
R Harris k1004 Nicholas U. Mayall 4-meter Telescope Mosaic R Harris k1004
ha12 H-alpha+12nm k1012 82.95 6698.53 Nicholas U. Mayall 4-meter Telescope Mosaic ha12 H-alpha+12nm k1012 ha12 H-alpha+12nm k1012 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.
wr475 WR 475 k1022 Nicholas U. Mayall 4-meter Telescope Mosaic wr475 WR 475 k1022 wr475 WR 475 k1022 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=4749A FWHM=51.32A PEAK TRANSMISSION=79.2%.
823 823_v1 k1027 Nicholas U. Mayall 4-meter Telescope Mosaic 823 823_v1 k1027
Rs Steidel k1043 Nicholas U. Mayall 4-meter Telescope Mosaic Rs Steidel k1043 Rs Steidel k1043
390 BATC k1052 ** Nicholas U. Mayall 4-meter Telescope Mosaic 390 BATC k1052 ** 390 BATC k1052 **
705 BATC k1060 ** Nicholas U. Mayall 4-meter Telescope Mosaic 705 BATC k1060 ** 705 BATC k1060 **
C Washington c6029 1075.00 3850.00 Nicholas U. Mayall 4-meter Telescope Mosaic
Barr J Band Filter Nicholas U. Mayall 4-meter Telescope Flamingos Barr J Band Filter Barr J Band Filter Cuton: 1.170 - Cutoff: 1.326
1060 blocker, 1 μm blocker, 1056 + 1063 blocker 1063.50 Nicholas U. Mayall 4-meter Telescope NEWFIRM 1060 blocker, 1 μm blocker, 1056 + 1063 blocker Use with 1401, 1402
H1, Yale H1 174.70 1555.70 Nicholas U. Mayall 4-meter Telescope NEWFIRM Use with 3203
KP1495 78.15 6685.37 Nicholas U. Mayall 4-meter Telescope KOSMOS KP1495 KP1495 KOSMOS Approved KPNO 4in. Filter.
WG-345 0.00 0.00 Nicholas U. Mayall 4-meter Telescope RC Spectrograph WG-345 WG-345 Sharp-Cut Filter. Cutoff filter: no transmission peak, FWHM is undefined.
RG-695 0.00 0.00 Nicholas U. Mayall 4-meter Telescope RC Spectrograph RG-695 RG-695 Sharp-Cut Filter. Cutoff filter: no transmission peak, FWHM is undefined.
I Nearly-Mould k1005 1914.59 8204.53 Nicholas U. Mayall 4-meter Telescope Mosaic I Nearly-Mould k1005 I Nearly-Mould k1005 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.
ha12 H-alpha+12nm k1012 Nicholas U. Mayall 4-meter Telescope Mosaic ha12 H-alpha+12nm k1012 ha12 H-alpha+12nm k1012 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=6672A, FWHM=83A, PEAK TRANSMISSION=87.3%.
wrhe2 WR HeII k1023 50.31 4702.60 Nicholas U. Mayall 4-meter Telescope Mosaic wrhe2 WR HeII k1023 wrhe2 WR HeII k1023 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.
823 823_v1 k1027 Nicholas U. Mayall 4-meter Telescope Mosaic 823 823_v1 k1027 823 823_v1 k1027 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) and the CTIO 4m (f/2.9). At the KPNO 4m the properties of this filter are: CWL=8170A, FWHM=71A, PEAK TRANSMISSION=91.5%.
Us solid U k1044 588.20 3651.81 Nicholas U. Mayall 4-meter Telescope Mosaic Us solid U k1044 Us solid U k1044 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.
420 BATC k1053 ** Nicholas U. Mayall 4-meter Telescope Mosaic 420 BATC k1053 ** 420 BATC k1053 ** 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.
755 BATC k1061 ** Nicholas U. Mayall 4-meter Telescope Mosaic 755 BATC k1061 ** 755 BATC k1061 ** 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.
M Washington c6007 1020.00 5020.00 Nicholas U. Mayall 4-meter Telescope Mosaic M Washington c6007 M Washington c6007 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.
Barr H Band Filter Nicholas U. Mayall 4-meter Telescope Flamingos Barr H Band Filter Barr H Band Filter Cuton: 1.495 - Cutoff: 1.776
J 241 158.00 1246.00 Nicholas U. Mayall 4-meter Telescope NEWFIRM Use with 2103. These filters have never been used in NEWFIRM
H2, Yale H2 168.30 1705.90 Nicholas U. Mayall 4-meter Telescope NEWFIRM Use with 3204
KP1496 84.11 6742.88 Nicholas U. Mayall 4-meter Telescope KOSMOS KP1496 KP1496 KOSMOS Approved KPNO 4in. Filter.
WG-360 0.00 0.00 Nicholas U. Mayall 4-meter Telescope RC Spectrograph WG-360 WG-360 Sharp-Cut Filter. Cutoff filter: no transmission peak, FWHM is undefined.
RG-830 0.00 0.00 Nicholas U. Mayall 4-meter Telescope RC Spectrograph RG-830 RG-830 Sharp-Cut Filter. Cutoff filter: no transmission peak, FWHM is undefined.
I Nearly-Mould k1005 Nicholas U. Mayall 4-meter Telescope Mosaic I Nearly-Mould k1005 I Nearly-Mould k1005
ha16 H-alpha+16nm k1013 81.10 6730.72 Nicholas U. Mayall 4-meter Telescope Mosaic ha16 H-alpha+16nm k1013 ha16 H-alpha+16nm k1013 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.
wrhe2 WR HeII k1023 Nicholas U. Mayall 4-meter Telescope Mosaic wrhe2 WR HeII k1023 wrhe2 WR HeII k1023 Below is a plot of this filter as simulated in different f/ratio beams. At the KPNO 4m the properties of this filter are: CWL=4695A FWHM=51.34A PEAK TRANSMISSION=74.83%.
918R 918R_v1 k1028 81.22 9210.96 Nicholas U. Mayall 4-meter Telescope Mosaic 918R 918R_v1 k1028 918R 918R_v1 k1028 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.
Us solid U k1044 Nicholas U. Mayall 4-meter Telescope Mosaic Us solid U k1044 Us solid U k1044
420 BATC k1053 ** Nicholas U. Mayall 4-meter Telescope Mosaic 420 BATC k1053 ** 420 BATC k1053 **
755 BATC k1061 ** Nicholas U. Mayall 4-meter Telescope Mosaic 755 BATC k1061 ** 755 BATC k1061 **
D51 DDO 51 c6008 154.00 5130.00 Nicholas U. Mayall 4-meter Telescope Mosaic D51 DDO 51 c6008 D51 DDO 51 c6008 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.
Barr Ks Band Filter Nicholas U. Mayall 4-meter Telescope Flamingos Barr Ks Band Filter Barr Ks Band Filter Cuton: 1.990 - Cutoff: 2.305
J 253 158.00 1252.00 Nicholas U. Mayall 4-meter Telescope NEWFIRM Use with 2103.
H1 + 2 blocker, Yale H1 +2 blcoker 472.00 1622.00 Nicholas U. Mayall 4-meter Telescope NEWFIRM Use with 3101, 3102, 3201, 3202
4-96 1756.27 4724.00 KPNO 2.1-meter Telescope GoldCam 4-96 4-96 Bandpass Filter.
OG-550 0.00 0.00 KPNO 2.1-meter Telescope GoldCam OG-550 OG-550 Sharp-Cut Filter. Cutoff filter: no transmission peak, FWHM is undefined.
CUSO4 liq 0.00 0.00 KPNO 2.1-meter Telescope KPNO 2-Inch Filter
kp1215 69.00 3536.00 KPNO 2.1-meter Telescope KPNO 2-Inch Filter kp1215 check plot--looks clear!
kp1310a 476.00 3615.00 KPNO 2.1-meter Telescope KPNO 2-Inch Filter nearly mould u-omega
kp1221 69.00 4089.00 KPNO 2.1-meter Telescope KPNO 2-Inch Filter kp1221
kp1404_1 1072.00 4329.00 KPNO 2.1-meter Telescope KPNO 2-Inch Filter kp1404_1 Harris set bg12,bg39,gg385
kp1412 76.00 4412.00 KPNO 2.1-meter Telescope KPNO 2-Inch Filter kp1412 backup for kp802-janos
kp1265_14 1182.00 4460.00 KPNO 2.1-meter Telescope KPNO 2-Inch Filter kp1265_14 mould system
kp1523 16.00 4692.00 KPNO 2.1-meter Telescope KPNO 2-Inch Filter kp1523 nebular set replaces kp1293