Taking Data Commands

The same commands can be used for the slit viewer and the spectrograph. We distinguish between these two systems by using a suffix. A v is for the slit viewer whereas an s is for the spectrograph.

tint(v/s) [t]	Sets the integration time to t seconds. If no argument is given, the current setting is returned. It includes the readtime.
goi(v/s) [n]	Takes an exposure and writes the file into the outdir directory. If n is specified, n-sequential images will be taken
sampmode(v/s) [type [n]]	Sets the sampling mode to one of n. Where n is 1 for ramp, 2 for CDS, 3 for Fowler (MCDS), or 4 for single read. (CDS = correlated double sampling; MCDS = multiple correlated double sampling.) If no arguments are given, the current mode is returned. The up-the-ramp and CDS modes have not been fully tested. The way to obtain CDS is to use MCDS with nsamp(v/s) of 1.
nsamp(v/s) [n]	Sets the number of MCDS mode reads to n. For example, for CDS set this to 1.
show(v/s)	Display the current settings. The following is an example for the output for the command `shows` for CDS: sampmode = 3 itime = 120.0000000 seconds numreads = 2 numfs = 1 coadds = 1 framesperbuff = 2 calcreads = 0 writeall = 1 readtime = 1.2020000 seconds rditime = 120.0000000 cdsmode = 1 framenum = 61 outdir = /usr/local/home/nires1/test2 testdir = /usr/local/home//niresdev/test
coadd(v/s) [n]	Sets the number of coadds to n. If n is not specified, the current value is returned. Note that the data numbers in the resultant image will be the sum of all coadded frames (i.e., the data are not scaled by the number of coadds).
frame(v/s) [n]	Sets the next frame number to n. If n is not specified, the current value is returned.
obj(v/s) [s]	Sets the object name to s. If s is not specified, the current name is returned.

Examples

A 2 second CDS observation with the SVC

Set the sampling mode sampmodev 3.
```
 setting sampmode = 3 (wait)
```
Set the number of reads to 1 nsampv 1.
```
 setting numfs = 1 (wait) 
```
Set the exposure time tintv 2.
```
setting itime = 2 (wait)
```

Check the setting

 showv

                      sampmode = 3
                         itime = 2.0000000 seconds
                      numreads = 2
                         numfs = 1
                        coadds = 1
                     calcreads = 0
                      writeall = 0
                      readtime = 1.4800000 seconds
                       rditime = 2.0000000
                       cdsmode = 1
                      framenum = 1
                        outdir = /s/sdata1500/nireseng/2018feb20/
                       testdir = /tmp

Observe goiv

 Taking frame #1
wfgv: Time estimate = 35 seconds (includes 30 seconds for overhead.
wfgv: Waiting for exposure to end.
........OK
Took file /s/sdata1500/nireseng/2018feb20//v180222_0001.fits

A 300 second Fowler 16 observation with the Spectrometer

Set the sampling mode sampmodes 3.
```
 setting sampmode = 3 (wait)
```
Set the number of reads to 16 nsamps 16.
```
 setting numfs = 16 (wait) 
```
Set the exposure time tints 300.
```
setting itime = 300 (wait)
```

Check the setting

 shows

                      sampmode = 3
                         itime = 300.0000000 seconds
                      numreads = 32
                         numfs = 16
                        coadds = 1
                 framesperbuff = 2
                     calcreads = 0
                      writeall = 1
                      readtime = 1.2020000 seconds
                       rditime = 2.0000000
                       cdsmode = 1
                      framenum = 1
                        outdir = /s/sdata1500/nireseng/2018feb20/
                       testdir = /tmp

Observe gois
```
 
```

A 1 second CDS observation with the SVC

Set the sampling mode sampmodev 3.
```
 setting sampmode = 3 (wait)
```
Set the number of reads to 1 nsampv 1.
```
 setting numfs = 1 (wait) 
```
Set the exposure time modify -s nids itime=1.
```
setting itime = 1 (wait)
```

Check the setting

 showv

                      sampmode = 3
                         itime = 1.0000000 seconds
                      numreads = 2
                         numfs = 1
                        coadds = 1
                     calcreads = 0
                      writeall = 0
                      readtime = 1.4800000 seconds
                       rditime = 2.0000000
                       cdsmode = 1
                      framenum = 2
                        outdir = /s/sdata1500/nireseng/2018feb20/
                       testdir = /tmp

Observe goiv
```
 
```