We never opened the dome tonight, due to high winds. And in Yokohama it rained hard all day.
Manny went down and Dan came up.
Dan and Amali measured voltages on various pins of the SAPHIRA under Suresh’s guidance. Based on their measurement, the detector temperature matches what is observed by the cold head. So it is not a temperature issue and likely an electronics issue. The next step was to measure two separate voltages to ensure they are correct. They were all around 5V which is where they were supposed to be. Suresh is now crunching the data to see if it gives any other clues to the IR WFS behavior.
The word of the night is たいふう (Typhoon) because apparently all this rain in Yokohama today was actually a small typhoon.
Tonight we worked more on alignment of the WFS pupils (both WFS’s). At the start of the night we attached a cardboard “knife edge” to the ASM so that we could compare the primary mirror and secondary mirror images.
MMT ASM hanging in the pre-twilight sky with a cardboard “knife edge” attached to posts.
Here’s the resulting image on the ZWO:
Top line is ASM knife edge; Bottom line is Primary Mirror cover knife edge.
And here’s the result on ARIES:
It’s flipped from ZWO here — top is Primary knife edge and bottom is ASM knife edge.
And here are the Vis pyramid pupils:
I think left: Primary, right: ASM knife edge.
Checking optics/focus: double knife edge test using primary mirror cover partially lowered and cardboard over ASM (mounted on posts). VIS: – Expectation: one edge would be sharper if said edge was closer to point of focus. – Observation: neither edge is sharp. Fall off on both edges is about 3 pixels on viswfs_pupils. – Assessment: Focal point is near primary, pupil plane inside topbox is somewhat correct.
Next we worked on the IR WFS. We could see the IR source on the SAPHIRA, but only just barely could see the white-light source, and when we went to a really bright and red star (Arcturus) we couldn’t see it. The dark counts were around 30,000 and looked normal (the full well depth is around 100,000), but when Suresh did an up-the-ramp test (which usually saturates after ~20 steps) it saturated after ~5 steps, and wasn’t enough steps to see if it was linear. So now we think either there is a thermal short or some thermal problem, or perhaps a readout/reset problem. TBD.
So we went back to Vis WFS alignment. Oli and Grant did some experiments changing the negative lens (first adjusting it, then removing it completely). Here is one result:
Vis WFS pupils. Top row: With neg lens. Bottom row: Without neg lens. Left: Filled pupil. Right: Knife edge primary.
We were closed for high winds from around 1:50am-3:30. During this time we put the negative lens back in. When we opened again we checked it out:
With Negative Lens — Before Removal (left) and After Re-Install (right)
We also tested going to a fainter (almost 7th mag) star and saw that we have plenty of photons on the CCID-75. Now with the winds close to our limit and having completed our engineering tests, the next thing is to get back to working on AO calibrations, but it was too close to dawn to get anywhere especially fighting the almost-limits-winds, so we called it a night.
Meanwhile at the conference there were great talks by Robin, Eden, and Jacob:
Today was the first day of the conference and my talk: “Commissioning MAPS, the MMT AO exoPlanet characterization System.” It went pretty well and it’s also nice to be done with that right at the start of the week! There were a few MAPS-ers in the audience and here’s a photo by one of them, Suresh:
Me giving my talk about commissioning MAPS … while commissioning MAPS remotely via Slack and Zoom.
Meanwhile back at MMTO, Brian had a message from Tim that it would be better to take the large tens-of-arcseconds mount offsets and offload them to the hexapod with zero-coma offsets. After he did that the team tested whether the star was still on the chief ray by rotating the instrument and watching it on ARIES — and it was good!
Oli came up tonight and he and Grant put in the ZWO pupil-imaging camera and did the same test we did yesterday to check if offsetting the star shifted the pupils, meaning they are mis-conjugated. However, they only saw a quarter of a pixel shift, or about 5um, which is about 2um out of tolerance (3um tolerance) and still close enough.
Suresh is also observing remotely from Japan and was in communication with the team about the IR camera weirdness from yesterday — the pressure seems high (or the reading is off), and/or the camera isn’t cool enough — so we turned it off for now and will pump on it all day while sleeping. Before that Grant/Oli/Manny went up to check the seating of the fibers in the Top Box.
Finally we tried to do some CACAO and began working our way through a few software bugs. We realized we needed Jared’s help with the pseudo inverse but he was at the conference reception.
We also started looking at our pupils more and decided to explore the alignment and pupil conjugation further. Oli and Grant tried adjusting the negative lens between the pellicle and pyramid. But even with 3 turns and almost all the way off, there was no noticeable difference in the pupil images:
But isn’t it strange that they still look so raggedy, and we can’t even see the spiders? We were wondering about this. So we decided to try and make something even more obvious to see. Some kind of a sharp edge. Shall we say a knife edge.
So we asked Brian to partially obscure the pupil by putting the primary mirror cover tarp about 1/3 of the way across. And here are the pupil images after this. First the ZWO:
ZWO pupil image (vis) with a knife-edge applied.
Which looks a lot like ARIES in K-band:
ARIES pupil image (K-band) with a knife edge applied.
And finally the Vis WFS pupils:
Vis pupils with a knife edge applied.
They all have a sharp knife edge from the primary mirror cover tarp. But the central obscuration is fuzzy on the Vis, whereas it is sharp in both ZWO and ARIES. And another curious thing is that the IR pupils have a sharper central obscuration.
IR (left) and Vis (right) pupils from last run (May 2024A). Note that the IR pupils have a sharper central obscuration.
It was about dawn and our brains were tired, so we will explore this a bit more tomorrow night. But it is curious that we can get a sharp knife edge on the Vis pupils but not a sharp central obscuration. Furthermore it is curious that the IR pupils did have a sharper central obscuration (last run).
The word of the night is Santoku. “Santoku means ‘Three Virtues’ or ‘To solve Three Problems’. The three virtues are meat, fish and vegetables, or slicing, dicing and mincing depending on your interpretation. This means that the Santoku is an all-around knife, suitable for the amateur home cook and the professional chef alike.” [source]
I’m going to write nightly updates like last run, even though this time I’m observing remotely from the SPIE Astronomical Telescopes & Instrumentation conference in Yokohama, Japan! Luckily Manny, Jenny, Craig, Grant, Dan, Amali, Bianca, Lauren, and Jorge are there to run things locally.
(Night 1 was 2024/06/14-15th but I’m writing this a little late, during Night 2.)
On Day 1 we installed the Top Box, ASM, and … ARIES! Welcome back to the MMT, Arizona infraRed Imager and Echelle Spectrograph!
Craig is working on installing ARIES while Dan is working in the Top Box.
We finished installing and setting up ARIES around 11pm. Then we checked the alignment — we couldn’t find the star at first, so Grant went up with an index card into the Top Box and saw that the star was off the dichroic. He and Brian worked to add mount offsets until they had the star on ARIES and the Acquisition Camera. They were quite large, 68” in az and 14” in el, but they did the job and the old hexapod positions successfully kept the star rotationaly centered on the ARIES imager channel. Manny thinks the mounting pin may be adding friction and causing the ASM to go on cock-eyed so perhaps the hexapod is good but the ASM install still needs some work.
Manny watches ARIES at the Cass
Periscope 1 was only moving 1 direction in one of its axes (TY). Luckily we had a spare controller so Grant swapped that out and got it working again!
We tried to check the IR WFS alignment but the camera seemed to be behaving strangely, at least there were some noisy channels. So at the end of the night we went on to the Vis WFS and did a few tests to analyze whether the raggedy edges of the pupils are due to either pupil misconjugation, chromatic bandpass effects, or chromatic ADC effects.
For this run we will have a word/phrase of the night. The word/phrase of the night is “Arigatou gozaimasu” or “Thank you very much [formal]”! It is very useful to say to pretty much all conbini, hotel, and wait staff in Japan.
As a thank you gift for Jared’s advising throughout my grad school experience, I wanted to give a knockout gift. Sebastiaan once offhandedly mentioned a useless box. Now, I LOVE useless boxes. When I was a teacher I stumbled across a useless box video which made me cackle; two years later my coworker gave me one as a christmas present on the staff work day before winter break. I showed it to everyone and wore the battery completely down that day. So what about a MagAO-X shaped useless box?
I’ll begin this post at the end with the final reveal. Behold, the MagAO-X useless box. Turn MagAO-X on and who is that turning it off?
Planning
Here is the original sketch from my notebook. Except for the location of the switch it came together mostly as originally planned.
I took inspiration for the vizz from this little tiger version. For the mechanism I used the one from a build-it-yourself useless box kit.
Sebastiaan helped me break into the lab (jk I know the code!) and measure everything so it can be perfectly to scale.
It is 1:10th scale.
Design for the legs:
And panels:
Fabrication
The box is made of wood panels and sticks you can get at any hobby store. I used a hobby knife the cut the panels and sticks, with lots of sanding to get them smooth. I didn’t get too many fabrication pics at this stage, which is a bummer. But once all the panels and pieces were glued I used wood filler to fill joints and places where the wood wasn’t flush. I bought a hand sander from Harbor Freight ($10! Bless Harbor Freight) and sanded everything smooth and flush.
I then glued on the wood panels and the little wood stick pieces around the top of what is supposed to look like the air table. The thinner panels tended to curl with the moisture from the wood glue so here I am using the glue to hold it down while drying.
One thing I wish I had pics of was that the DIY kit mechanism required me to buy a soldering iron and learn how to solder!
Because of the design of the DIY box kit, putting the switch on the front panels as originally planned didn’t work, because the gear box would have to positioned in such a way that the lid wouldn’t sit down all the way. So I improvised by cutting the lid and placing the switch so that it opened to the side. Here is the video of the first operational test of the mechanism.
You can’t see it here (but you can in later pics), but I put little hinges on the lid with the switch to enable opening it, and I used the hinges from the DIY kit for the side of the lid that needs to open. I also cut a door out of the back panel to enable changing the batteries.
I then set up a makeshift spray booth in my back yard. I removed the mechanism and gave it many coats of black, sanding in between to make the wood soft, and finished with a sealer.
Here is the assembled painted product. Notice the box of tiny gold hinges and the brand new soldering iron in the background!
Here is the mechanism from the DIY box kit. It’s mounted the bottom of the lid so that it rests down flat when not on, then pushes up the other side of the lid when turned on. There is a little reed switch behind the arm which opens the circuit, and a little wood protrusion from the back of the arm which depresses it. When the switch is flipped on, the current turns the motor to raise the arm up, the protrusion releases the reed switch. When the arm flips the switch, the current reverses and brings the arm back down until the protrusion depresses the reed switch again and breaks the circuit.
Here you can also see the battery door. I mounted the battery pack on the door so it’s easy to replace the batteries. I also put a fancy bead on the door as a fancy door handle, and a latch to hold the switch lid.
Next it was time for the details. I printed all the logos in secret using the office printer cause I don’t have a color printer. I painstakingly cut them out with an exacto knife trying to replicate the curves and white borders of the real stickers, then stuck them on with Mod Podge. At the time I was making this, the “Clean Top” sticker on MagAO-X was missing the e so I blacked it out with marker! (Now the whole thing is almost gone). I also glued little pieces of foil on the corners of the air table to mimic the corner bumpers, and cut circles out of gold craft foam for the eye piece port on the side.
Adding the stickers with a reference photo in the background:
For the panel clamps, I used beads. I found some large-ish black beads and small silver beads or close to the right size (I did measure them!) and glued them together, then glued them to the panels in the right place. This was a huge pain in the ass and I had to try a few different glues to find the one that made them actually stay stuck. I also used the small silver beads for the panel support screws.
For the handles I used a thick crafting wire, bent to the right size and shape, and covered it with electrical heat shrink tubing which shrinks to the size of the wire. I glued some black beads to the wire to help them stick to the panels.
Finally it was time for the vizz. I used brown and yellow fleece and sewed a little paw, which I stuffed a little bit and slid over the arm. I made toes by hand sewing little imprints with black thread. I had to make sure that the end of the arm still hit the switch, which involved moving the paw around a bit to find just the right spot. I then used fabric glue to glue the end of the fleece to the wood arm and used some yarn to tie it down for good measure.
The head took several tries. I got several rabbit patterns off etsy that had potentially suitable heads and tried to scale them to the correct size. It took several trial and errors on the best pattern and the right size. Once I had a suitable one I put little eyes and nose and whiskers, then made ears of just single pieces of fleece and hand sewed them on.
I put a little piece of velcro on the head and the bottom of the lid so that that head comes up when you activate the switch. I also attached a loosely stuffed fleece tube to the bottom of the head as a suggestion of a body.
Finally I sewed a little tail out of the brown fleece and glued a little strip of a darker brown fleece as the stripe down the tail. I glued and sewed the end shut and put a little piece of velcro on the top and under the hinge on the side of the box so it looked like a vizzy tail hanging out the side, but it won’t interfere with the hinge.
