Switch to grism mode

Assuming MIRC is at prism mode right now, to change to low resolution grism mode, here are the steps.

1. use the white light source in the lab, do fiber explore to align the fibers for all 6 beams. Then put the white light on beam 3 and 4.

2. move out the prism. You can turn the knob of the zaber mount manually to move out the prism, until it is completely out of the way.

3. Rotate in the grism. There are two knobs on the back of the MIRC dewar, the inner one controls the filters, and the outer one controls the spectral resolution (1 = open, 4 = low resolution grism). If mirc is at prism mode, the outer knob should be at 1. Rotate it to 4, which is the low resolution grism. You can do this manually.

4. Align the doublet. Now you shouldn't see any light on the detector if the readout of the detector is still set for the prism mode. You need to move down the mirc light to the top of the lower left quadrant (on the IRCam display). To do that, you will need to move the doublet to the left if you are facing the window of the detector. Or you can open the picoGui and move the X axis of the doublet.

5. Configure detector readout. Once you see mirc light at the top of the lower left quadrant (on the IRCam display), stop display, stop exposure, change to the setting on the IRCam gui to the standard prism mode: number of rows = 48, number of columns = 252, rows offset = 2 column offset = 2, nreads = 5, number of frames = 500... Then update the parameters and configure the camera again, start exposure, start display.

6. fine adjustment. You will move the doublet again for fine adjustment to balance the mirc light on the detector up and down, right and left. Then adjust the axis which doesn't have a knob and points off the table to balance the photometric channels up and down.