Summary Table
| Image scale: | 0.033 arcsec/pixel |
| Unvignetted Field of View: | 20x20 arcsec |
| Illuminated Circular Field: | 27.7 arcsec (840 pixel) diameter |
| Detector: | Teledyne H2RG |
| Filter/Aperture Wheels | ||
|---|---|---|
| Filter 1 | Filter 2 | Aperture |
| CaF-Kgrism | HGrism | Pinhole-100um |
| PupilViewer | Blank25 | Slit-100um-V |
| BrG-2.16 | Open | Half-field |
| H2-2.122 | Ch4-1.2 | Open |
| Ks | CH4-2.4 | Slit-100um-H |
| H | K | Finger |
| J | Wollaston | |
| Open | FeII | |
| Science (External) Filter Wheel | |
|---|---|
| Position | Filter |
| 1 | Open |
| 2 | ND2 |
| 3 | ND4 |
| 4 | 2.2/0.04 |
| 5 | Kcont |
| 6 | Hcont |
| Read Noise: | 21 e- with CDS 6 e- with 16 Reads 5 e- with 32 Reads | |||||||||||||||||
| Gain: | 2.35 e-/DN | |||||||||||||||||
| Linearity | ~30,000 DN (~70,500 e-) | |||||||||||||||||
| Minimum full frame readout time: | 1.46 seconds | |||||||||||||||||
| Windowing mode readout time: | 0.11 seconds with 100x100 square pixel region | |||||||||||||||||
| Measured Zero Points: ZP = 2.5 log10(N photons/sec) |
J = 22.3 H = 24.3 K = 23.5 Ks = | |||||||||||||||||
| Sky Backgrounds: |
J = 15.84 mag per square arcsec H = 13.85 mag per square arcsec K = 13.87 mag per square arcsec Ks = 14.60 mag per square arcsec | |||||||||||||||||
| Predicted Limiting Magnitudes: 300s Fowler sampling with 32 reads, S/N=5 |
| Filter | ShARCS 8 | ShARCS 16 |
| K Strehl | 0.6 | 0.8 |
| J | 21.30 | 22.28 |
| H | 20.48 | 21.03 |
| K | 18.71 | 19.02 |
| Ks | 18.92 | 19.24 |
Off-axis Guide Star limits
Both LGS and NGS AO observing require natural guide stars. Limits below are approximate, as the field of view for the off-axis guide stars are not circular. Also, the magnitude limits are color dependent. For more detailed information, see the ShaneAO user manual.
| Mode | Max distance to Guide Star | R Magnitude Limit |
|---|---|---|
| NGS | 10" | 12 (with TT Dichroic) 13.5 (with Mirror) |
| LGS | 60" | 18 |