This page provides a rough comparison between using NIRSPEC/SCAM behind AO and using NIRC-2 in imaging modes. Note that only imaging is covered here. Also note that we do not have sensitivity measurements for SCAM.

Filter complements

Note that NIRSPEC filters are mostly nonstandard bandpasses, with the exception of the K and K' filters.

NIRC-2
NIRSPEC/
SCAM
Filter
Central
Wavelength
FWHM
Filter
Central
Wavelength
FWHM
J
1.248
0.163
NIRSPEC-1
1.035
0.17
H
1.633
0.296
NIRSPEC-2
1.19
0.20
Ks
2.146
0.311
NIRSPEC-3 (J)
1.26
0.24
K'
2.124
0.351
NIRSPEC-4
1.415
0.35
K
2.196
0.336
NIRSPEC-5 (H)
1.612
0.375
L
3.776
0.700
NIRSPEC-6
1.925
0.75
M
4.670
0.241
NIRSPEC-7
2.222
0.805
Br-gamma
2.188
0.034
Brg
2.165
0.02
Kcont
    
CO
2.290
0.0225
Hcont
    
K
2.20
0.40
Fe II
    
K'
2.12
0.35
NB2.108
2.108
    

Note: The AO bench external filter wheel normally available for NIRSPAO observing is NOT available for NIRC2. One consequence of this is that there are no ND filters in the NIRC2 optical path to help avoid saturation on bright objects. However, there are other means for avoiding saturation with NIRC2. One way is to use the very short exposure times that are possible by using the sub-array capability of the detector.

>Detector

Note that NIRC-2 uses an InSb detector that is sensitive to 3-5 micron light, whereas the HgCdTe array used in SCAM is not.

NIRC-2
  
NIRSPEC/SCAM
10, 20, or 40 
pixel size
(milliarcsec) 
16.8
10, 20, or 40
field of view
(arcsec) 
4.3
38
readout noise
(electrons per pixel per read)
10
~52,000
linear limit
(electrons)
120,000