Space Telescope Science Institute
help@stsci.edu
Table of Contents Previous Next Index Print


Near Infrared Camera and Multi-Object Spectrometer Instrument Handbook for Cycle 17 > Chapter 8: Detector Readout Modes > 8.3 MULTIACCUM Predefined Sample Sequences(SAMP-SEQ)

8.3 MULTIACCUM Predefined Sample Sequences
(SAMP-SEQ)
For the user’s convenience, and to minimize the volume of commanding information to be sent to HST, a set of sequences has been defined which should cover nearly all applications of MULTIACCUM. These are listed in Table 8.2. The observer specifies the name of the sequence and the number of samples to be obtained. The SCAMRR and MCAMRR are to be used when the fastest temporal sampling is desired. The SPARS4, SPARS16, SPARS32, SPARS64, SPARS128 and SPARS256 sequences have relatively few readouts and may be helpful when two or more cameras are operated in parallel (in particular they generally permit a second and third camera to operate in parallel with a minimal impact on the operation of the primary camera). SPARSXX is also recommended for observations of fields where only faint targets are present. The STEPxX sequences all start with three rapid readouts and then are logarithmically spaced to provide a large dynamic range up to their defined time (e.g., STEP64 has log steps up to 64 seconds) and then revert to linear spacing. The STEPXX sequences are recommended for observations involving both bright and faint targets, where high dynamic range is required.
The fastest time to read a single camera is 0.203 seconds, while 0.303 seconds is the fastest time when more than one camera is used. Accordingly, the MULTIACCUM sequences have been set up so that the first read is always the fastest time possible. The second read for all of the sequences, except for the SCAMRR, has a time of 0.606 seconds.
Table 8.2: MULTIACCUM SAMP-SEQs.
0.203
1.218
2.233
3.248
4.263
0.406
1.421
2.436
3.451
4.466
0.609
1.624
2.639
3.654
4.669
0.812
1.827
2.842
3.857
4.872
1.015
2.030
3.045
4.060
5.075
0.303
1.818
3.333
4.848
6.363
0.606
2.121
3.636
5.151
6.666
0.909
2.424
3.939
5.454
6.969
1.212
2.727
4.242
5.757
7.272
1.515
3.030
4.545
6.060
7.575
Fastest possible operation with 2 or 3 cameras used in parallel.
0.303
3.989
8.979
13.969
18.959
0.606
4.987
9.977
14.967
19.957
0.995
5.985
10.975
15.965
20.955
1.993
6.983
11.973
16.963
21.953
2.991
7.981
12.971
17.961
22.951
Rapid reads up to 1 second then 1 second steps.
0.303
5.981
15.951
25.921
35.891
0.606
7.975
17.945
27.915
37.885
0.995
9.969
19.939
29.909
39.879
1.993
11.963
21.933
31.903
41.873
3.987
13.957
23.927
33.897
43.867
Rapid reads up to 2 seconds then 2 second steps.
0.303
7.981
47.951
87.921
127.891
0.606
15.975
55.945
95.915
135.885
0.995
23.969
63.939
103.909
143.879
1.993
31.963
71.933
111.903
151.873
3.987
39.957
79.927
119.897
159.867
Rapid reads up to 8 seconds then 8 second steps.
0.303
7.981
79.951
159.921
239.891
0.606
15.975
95.945
175.915
255.885
0.995
31.969
111.939
191.909
271.879
1.993
47.963
127.933
207.903
287.873
3.987
63.957
143.927
223.897
303.867
Rapid reads up to 16 seconds then 16 second steps.
0.303
7.981
127.969
287.969
447.969
0.606
15.975
159.969
319.969
479.969
0.995
31.969
191.969
351.969
511.969
1.993
63.969
223.969
383.969
543.969
3.987
95.969
255.969
415.969
575.969
Rapid reads up to 32 seconds then 32 second steps.
0.303
7.981
191.965
511.955
831.945
0.606
15.975
255.963
575.953
895.943
0.995
31.969
319.961
639.951
959.941
1.993
63.969
383.959
703.949
1023.939
3.987
127.967
447.957
767.947
1087.937
Rapid reads up to 64 seconds then 64 second steps.
0.303
7.981
255.961
895.931
1535.901
0.606
15.975
383.955
1023.925
1663.895
0.995
31.969
511.949
1151.919
1791.889
1.993
63.969
639.943
1279.913
1919.883
3.987
127.967
767.937
1407.907
2047.877
Rapid reads up to 128 seconds then 128 second steps.
0.303
7.981
255.961
1535.961
2815.961
0.606
15.975
511.961
1791.961
3071.961
0.995
31.969
767.961
2047.961
3327.961
1.993
63.969
1023.961
2303.961
3583.961
3.987
127.967
1279.961
2559.961
3839.961
Rapid reads up to 256 seconds then 256 second steps.
0.303
16.004
36.014
56.024
76.034
0.606
20.006
40.016
60.026
80.036
3.998
24.008
44.018
64.028
84.038
8.000
28.010
48.020
68.030
88.040
12.002
32.012
52.022
72.032
92.042
0.303
64.000
144.005
224.010
304.015
0.606
80.001
160.006
240.011
320.016
15.997
96.002
176.007
256.012
336.017
31.998
112.003
192.008
272.013
352.018
47.999
128.004
208.009
288.014
368.019
Similar to STEP16 but without the rapid initial readouts.
0.303
128.004
288.004
448.004
608.004
0.606
160.004
320.004
480.004
640.004
32.004
192.004
352.004
512.004
672.004
64.004
224.004
384.004
544.004
704.004
96.004
256.004
416.004
576.004
736.004
Similar to STEP32 but without the rapid initial readouts.
0.303
255.988
575.978
895.968
1215.958
0.606
319.986
639.976
959.966
1279.956
63.994
383.984
703.974
1023.964
1343.954
127.992
447.982
767.972
1087.962
1407.952
191.990
511.980
831.970
1151.960
1471.950
Similar to STEP64 but without the rapid initial readouts.
0.303
512.000
1152.005
1792.010
2432.015
0.606
640.001
1280.006
1920.011
2560.015
127.997
768.002
1408.007
2048.012
2688.017
255.998
896.003
1536.008
2176.013
2816.018
383.990
1024.004
1664.009
2304.014
2944.019
Similar to STEP128 but without the rapid initial readouts.
0.303
1023.996
2303.996
3583.996
4863.996
0.606
1279.996
2559.996
3839.996
5119.996
255.996
1535.996
2815.996
4095.996
5375.996
511.996
1791.996
3071.996
4351.996
5631.996
767.996
2047.996
3327.996
4607.996
5887.996
Similar to STEP256 but without the rapid initial readouts.

Table of Contents Previous Next Index Print