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Available filters are shown in the table below. To avoid saturation due to the strong emission from the diamond window, ND filters are needed for observations in the L and M bands.
| Name | Center wavelength (um) | Band width (FWHM; um) | Note |
| J | 1.250 | 0.168 | |
| H | 1.644 | 0.292 | |
| Ks | 2.138 | 0.320 | |
| L'+OD2 | 3.847 | 0.665 | OD2 means an ND filter with OD=2 required to avoid saturation. |
| M'+OD3 | 4.713 | 0.397 | OD3 means an ND filter with OD=3 required to avoid saturation. |
Saturation limits are calculated as shown in the Table below. An ND filter with OD=4 may also be available. By using ND filters (not applicable for the J and H bands) or performing defocused observations, objects brighter than the flux densities below, although such observations require special care for calibration.
| Name | Saturation limit |
| J | 120 mJy |
| H | 70 mJy |
| Ks | 80 mJy |
| L'+OD2 | 10 Jy |
| M'+OD3 | 800 Jy |
Noise-equivalent flux density for one exposure is calculated as shown in the figure below. Corresponding 1-sigma 1-sec sensitivity is also plotted. This calculation assumes aperture photometry with an aperture diameter of 2.5 times the FWHM of the PSF in the medium seeing condition (see here). Since readout noise (assumed 100e-/read) is the main noise source in short exposures, sensitivity improves with longer exposure times. PWV dependency is not significant in these bands. The truncation in the right edge of each band shows the longest exposure time before saturation except for the J band. The sensitivities of the L' and M' bands are significantly worse due to the ND filters and the strong absorption of the diamond window.
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| Noise equivalent flux density for one exposure. Corresponding 1-sigma 1-sec sensitivity is shown by dotted lines. |
