This wiki page is a guide to use the Differential Image Motion Sensor Using Multiapertures (DIMSUM) instrumentation that was installed to Aux Tel between December 6th and 16th. I am currently writing this as a wiki page to be able to get feedback during the process of documentation. Once everything is finalized I can create a pdf file if requested.
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This should not happen in any regular case unless someone who really knows what they are doing played with the controls. This happens when the mirror lockup is turned on. Turn mirror lock up off.
Analysis
See Software Analysis of Differential Image Motion For DIMSUM Vol 1 for the analysis of DIMSUM data.
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(base) stubbslab@auxtel-macmini03 ~ % gphoto2 --get-config aperture
Label: Aperture
Readonly: 0
Type: RADIO
Current: 5.6
Choice: 0 5
Choice: 1 5.6
Choice: 2 6.3
Choice: 3 7.1
Choice: 4 8
Choice: 5 9
Choice: 6 10
Choice: 7 11
Choice: 8 13
Choice: 9 14
Choice: 10 16
Choice: 11 18
Choice: 12 20
Choice: 13 22
Choice: 14 25
Choice: 15 29
Choice: 16 32
Choice: 17 36
END
3 am Chile Dec 6. Kicked off repeat 500 ./CommunicateTrial2023.sh, along with python data xfer script. This is with stopped-down aperture.
Wed Dec 6 2023, Pachon
I was confused by inapprorpriate CR to FITS file conversion. The PSF's aren't saturated. In fact we could use more flux.
This method works well (on Chris' laptop) for file conversion:
mdcraw -o 1 -D -4 -T CU2A0987.CR2
convert CU2A0987.tiff CU2A0987.fits
That makes a nice, well-behaved FITS file. PSF is about 40 microns across, which I think means for a 200mm focal length we are basically getting resolved images of the fiber tips, for a 600 micron fiber.
For next time, perhaps use smaller fiber diameters. 200 microns would be good.
I used gphoto2 to change the lens aperture to f/6.3. I was worried we were getting aberrations at faster f-number but I now think it's just fiber tip illumination non-uniformity.
I also removed the ND filter in the optical path. There is now no filter in the beam. Wasn't able to debug why no light in the vertical panel. Might just leave that for next time. It's vignetted by telescope anyway.
started another data collection into 23-12-06_observing_run directory on La Cie disk.
Thurs Dec 7, 2023 Pachon
Tasks:
Try fixing second outrigger panel- use different feed fiber?
investigate mounting schemes for mirror seeing monitoring- mount DUMSUM on Aux Tel somewhere. Maybe second Nasmyth port?
Pack up items.
Truss OD on AuxTel is 2.250 inches in diameter
upper rail on stairs is 2 inches diameter
lower rail on stairs is 3/4 inches diameter.
10 am local Dec 7: I swapped the drive optical fiber for upper extension to one that was plugged into the array. Need to see if that worked.
Battery in calipers iis LR44. Need to bring down more.
Any repositioning of DIMSUM to include mirror seeing would have to go for the ride w telescope elevation axis, and would only work when mirror covers are open. Ordered parts for more DIMSUMS: two monochrome Canon 5D IV from MaxMax. More Xenon flash sources from Hamamatsu, and this from B&H
Readonly: 0
Type: RADIO
Current: 5.6
Choice: 0 5
Choice: 1 5.6
Choice: 2 6.3
Choice: 3 7.1
Choice: 4 8
Choice: 5 9
Choice: 6 10
Choice: 7 11
Choice: 8 13
Choice: 9 14
Choice: 10 16
Choice: 11 18
Choice: 12 20
Choice: 13 22
Choice: 14 25
Choice: 15 29
Choice: 16 32
Choice: 17 36
END
3 am Chile Dec 6. Kicked off repeat 500 ./CommunicateTrial2023.sh, along with python data xfer script. This is with stopped-down aperture.
Wed Dec 6 2023, Pachon
I was confused by inapprorpriate CR to FITS file conversion. The PSF's aren't saturated. In fact we could use more flux.
This method works well (on Chris' laptop) for file conversion:
mdcraw -o 1 -D -4 -T CU2A0987.CR2
convert CU2A0987.tiff CU2A0987.fits
That makes a nice, well-behaved FITS file. PSF is about 40 microns across, which I think means for a 200mm focal length we are basically getting resolved images of the fiber tips, for a 600 micron fiber.
For next time, perhaps use smaller fiber diameters. 200 microns would be good.
I used gphoto2 to change the lens aperture to f/6.3. I was worried we were getting aberrations at faster f-number but I now think it's just fiber tip illumination non-uniformity.
I also removed the ND filter in the optical path. There is now no filter in the beam. Wasn't able to debug why no light in the vertical panel. Might just leave that for next time. It's vignetted by telescope anyway.
started another data collection into 23-12-06_observing_run directory on La Cie disk.
Thurs Dec 7, 2023 Pachon
Tasks:
Try fixing second outrigger panel- use different feed fiber?
investigate mounting schemes for mirror seeing monitoring- mount DUMSUM on Aux Tel somewhere. Maybe second Nasmyth port?
Pack up items.
Truss OD on AuxTel is 2.250 inches in diameter
upper rail on stairs is 2 inches diameter
lower rail on stairs is 3/4 inches diameter.
10 am local Dec 7: I swapped the drive optical fiber for upper extension to one that was plugged into the array. Need to see if that worked.
Battery in calipers iis LR44. Need to bring down more.
Any repositioning of DIMSUM to include mirror seeing would have to go for the ride w telescope elevation axis, and would only work when mirror covers are open.
Ordered parts for more DIMSUMS: two monochrome Canon 5D IV from MaxMax. More Xenon flash sources from Hamamatsu, and this from B&H
Jan 27 2024, CWS
We need to do better coupling light into fibers. Thor labs sells and 1:2, 1:4 and 1:7 fibers with 200,400, 600 micron cores.
The 1:2 version comes in 1mm core as well.
Let's assume we want the final emitting end to be smallish fiber, 200 microns.
If it's a 1:4 bundle then we need to feed it with a larger one, at least 400. 600 would be even better.
getting a uniform light distribution on output face would benefit from a mode scrambler.
So how about 1:4 plugged into the light source, largest possible is 600 micron fiber. That a diameter of about 1.2mm, and light into each should be the same.
Each of those feeds 1:4 200 micron bundle. That gives us 16 sources, each 200 microns diameter.
So we should order one 600 micron 1:4 and four 200 micron 1:4's.
The SMA threads are 1/4-36. Digikey sells them, part number A104989-ND. Bought 100 of them.
Asked Helen to place this order since credit card failed.
