Switch to prism mode: Difference between revisions
New page: Assuming MIRC is at grism mode right now, to change to prism 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. ... |
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The alignment doesn't have to be precise, just judging by your eyes is enough. | The alignment doesn't have to be precise, just judging by your eyes is enough. | ||
4. Align the doublet. | 4. Align the doublet. Now you shouldn't see any light on the detector | ||
Now you shouldn't see any light on the detector if the readout of the detector | if the readout of the detector is still set for the grism mode. You need to move up | ||
is set for the grism mode. | 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 right 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 = 16, number of columns = 252, rows offset = 4 | |||
column offset = 2, nreads = 5, number of coherence = 1000... 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. | |||
Revision as of 23:14, 18 April 2012
Assuming MIRC is at grism mode right now, to change to prism 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. Rotate out 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 low resolution grism mode, the outer knob should be at 4. Rotate it to 1, which means open. You can do this manually.
3. move in the prism. You can turn the knob of the zaber mount manually to move the prism until it is aligned with the doublet and the window of the detector. The alignment doesn't have to be precise, just judging by your eyes is enough.
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 grism mode. You need to move up 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 right 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 = 16, number of columns = 252, rows offset = 4 column offset = 2, nreads = 5, number of coherence = 1000... 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.
