JWST NIRCam offers 29 bandpass filters in the short wavelength (0.6–2.3 μm) and long wavelength (2.4–5.0 μm) channels.
Parent page: NIRCam Instrumentation
Each of the two NIRCam modules carries a nearly identical set of 29 filters. Most filters are located in the filter wheel and are used in combination with pupil wheel elements including CLEAR, grism, coronagraph Lyot stops, and weak lenses.
The 6 filters located in the pupil wheels (F162M, F164N, F323N, F405N, F466N, and F470N) include their individual pupil aperture stops and are used in combination with a second filter in the filter wheel (F150W2, F322W2, or F444W) because the filter wheels contain no CLEAR elements.
Filter transmissions (including all system throughputs) are plotted in Figures 1 and 2; ASCII tables are also provided.
Throughputs vary somewhat between the two modules, especially at long wavelengths due to differences in detector quantum efficiencies. Total throughputs are shown in Figures 1 and 2 for each module, individually and averaged between modules.
Table 1. Numbers of extra-wide, wide, medium, and narrow filters in each wavelength channel
|Filters||R = λ/Δλ|
Short wavelength channel
Long wavelength channel
The filter transmission curves archive file contains:
- both data (ASCII) and plots (PDF);
- data for each individual module as well as averages of both modules;
- filter only, NIRCam only, and the total system throughput data;
- measured/expected transmissions for the filters, dichroic, optics, and the JWST OTE;
- detector quantum efficiencies (QE).
Module-averaged total system transmission curves for all filters are available via the links in column 1 of Tables 2 and 3.
Tables 2 and 3. Characteristics of filters in the short and long wavelength channels
Short wavelength channel (0.6–2.3 µm)
|F140M||1.405||0.142||0.397||1.331||1.479||Cool stars, H2O, CH4|
|F162M||1.627||0.168||0.416||1.542||1.713||Cool Stars, off-band for H2O|
|F150W2||1.659||1.175||0.415||1.008||2.334||Blocking filter for F162M, F164N, and DHS|
|F182M||1.845||0.237||0.454||1.722||1.968||Cool stars, H2O, CH4|
Long wavelength channel (2.4–5.0 µm)
|F322W2||3.232||1.356||0.443||2.430||4.013||Background min. Primarily used w/ grisms. Blocking filter for F323N.|
|F360M||3.624||0.370||0.458||3.427||3.814||Brown dwarfs, planets, continuum|
|F410M||4.082||0.438||0.469||3.864||4.301||Brown dwarfs, planets, H2O, CH4|
|F444W||4.408||1.029||0.474||3.880||4.986||General purpose. Blocking filter for F405N, F466N, F470N.|
|F480M||4.874||0.300||0.317||4.662||4.977||Brown dwarfs, planets, continuum|
Rieke, G. H., Blaylock, M., Decin, L., et al. 2008, AJ, 135, 2245
Absolute Physical Calibration in the Infrared
Tokunaga, A. T., & Vacca, W. D., 2005 PASP 117, 421
The Mauna Kea Observatories Near-Infrared Filter Set. III. Isophotal Wavelengths and Absolute Calibration
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