NSFCam Filter Transmission Profiles

Transmission profiles are available for the filters listed below. The profiles are available as gif images, as postscript plots, or as ascii files containing the actual data. The images/plots are available at two wavelength scales: the 1-6 micron range over which the detector is sensitive (full range) and the wavelength region near the central wavelength of the filter. (Not all the plots have been made yet; however, all the data files are available.) The data files contain two columns, giving the wavelength in microns and the corresponding absolute transmissions (on a scale of 0 to 1).

In order to suppress long wavelength red-leaks, many of the filters are used in conjunction with an uncoated PK50 blocker located in the CVF wheel. For these filters we present the transmission profiles obtained both with and without the blocker. Both the H band filter and the Brackett gamma filter have a blocker sandwiched with them in the filter wheel; for these filters we give only the tranmission profiles including the blocker. For all other filters we give only the transmission of the filter itself; however, we also give the transmission of the PK50 filter, so that the profiles can be combined if desired.

Note that many of the broadband filters listed here have been replaced with the new ``Mauna Kea'' versions (whose transmission profiles are also given below) and are no longer used. The profiles are presented here for completeness. None of the Mauna Kea filters requires the use of a PK50 blocker.


Broad Band Filters
Filter GIF Image PS Plot Ascii Data Files
J (replaced with J_MK) Full Range Central Region Full Range Central Region filter plus blocker
H (replaced with H_MK) Full Range Central Region Full Range Central Region ... plus blocker
K (replaced with K_MK) Full Range Central Region Full Range Central Region filter ...
K´ (replaced with K´_MK) Full Range Central Region Full Range Central Region filter plus blocker
Ks (replaced with Ks_MK) Full Range Central Region Full Range Central Region filter plus blocker
L Full Range Central Region Full Range Central Region filter ...
L´ (replaced with L´_MK) Full Range Central Region Full Range Central Region filter ...
M Full Range Central Region Full Range Central Region filter ...
M´ (replaced with M´_MK) Full Range Central Region Full Range Central Region filter ...
PK50 Blocker Full Range ... Full Range ... filter ...



New ``Mauna Kea'' Broad Band Filters
Filter GIF Image PS Plot Ascii Data Files
J_MK Full Range Central Region Full Range Central Region filter
H_MK Full Range Central Region Full Range Central Region filter
K_MK Full Range Central Region Full Range Central Region filter
K´_MK Full Range Central Region Full Range Central Region filter
Ks_MK Full Range Central Region Full Range Central Region filter
L´_MK Full Range Central Region Full Range Central Region filter
M´_MK Full Range Central Region Full Range Central Region filter

JPEG plots of the transmission profiles of the new ``Mauna Kea'' infrared filter set are also available for the following filters:

J , H , K , Kshort , K' , L' , M'


Narrow Band Filters
Filter GIF PS Ascii Data Files
Paschen gamma 1.094 µ Full Range Central Region Full Range Central Region filter plus blocker
Paschen beta 1.282 µ Full Range Central Region Full Range Central Region filter plus blocker
Brackett gamma 2.166 µ Full Range Central Region Full Range Central Region ... plus blocker
He I 1.083 µ Full Range Central Region Full Range Central Region filter plus blocker
Fe II 1.644 µ Full Range Central Region Full Range Central Region filter plus blocker
H2 v=1-0 S(1) 2.122 µ Full Range Central Region Full Range Central Region filter plus blocker
H2 v=2-1 S(1) 2.248 µ Full Range Central Region Full Range Central Region filter plus blocker
CO bandhead 2.295 µ > Full Range Central Region Full Range Central Region filter plus blocker
Continuum (K-band) 2.26 µ Full Range Central Region Full Range Central Region filter plus blocker
Spencer 1.7 µ Full Range Central Region Full Range Central Region filter ...
Spencer 2.3 µ Full Range Central Region Full Range Central Region filter ...


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Maintained by Bobby Bus (sjb@irtf.ifa.hawaii.edu)