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NAS Fitcheck Day 6: Getting Ready

We start our move up to the Clay tomorrow, so today was mainly spent getting ready. We disconnected and drained the supply lines for the NAS cooling system.

Laird, Jason, and Tyson move some hose.

That hose, along with a bunch of power and data cables, was made into a cable and we started wrapping it around the NAS. The NAS will move up to the Aux building between the telescopes tomorrow.

Another detail to worry about is balancing the NAS so we don’t overload the rotator motors. The crew finished a counter-weight today, and Alan and Tyson installed it.

A counter-weight to make the NAS easy to rotate. It's on top - most of the heavy stuff is on the bottom!

Meanwhile, we also tested the main chiller which keeps the ASM itself cool.

Jason in the exhaust tunnel.

Emilio wrote some software to monitor and control the system. See below for a video of it in action during the above test.

Control software for our ASM cooler.

Here's Juan next to the PLC box. Thanks to everybody here and back at Steward who helped make this happen.

While everybody else has been getting their hands dirty, I’ve been putting our VisAO camera through some tests (mainly focusing). As I complain about regularly, we never get very much time to see what it can do. Here are some reduced images with our coronagraphic occulting spot.

Our coronagraphic occulting spot blocks our SDSS i' PSF.
Same, but in our y-ish 1 micron filter.

Tonight’s quote: “Hey Laird, how long do you plan to use this instrument? I mean it’s not just for Jared’s PhD right?” (Jason Lewis)

Hector and Jose surprised us with Sushi at lunch.
I noticed this nice little indoor garden today for the first time.
I did get out of the lab just in time to see the top of the Sun.

NAS Fitcheck Day 5: Wrapping Up The Glycol

Tyson and Jason finished designing our new cable wrap system. Here are some views of the plan (note: if you are an important person at Magellan, check your email for more):

The cable loops under the platform as the NAS rotates.
The pipe guides the cable down through the hole.

Luckily Juan found a piece of 4″ PVC pipe to use for the “stove pipe”. I don’t want to know where it was used before.

This morning we declared our CCD cooling system air-tight and started running water through it. Here are some videos of the filling, pressurizing, and starting of the pump for the first time.

Laird ponders the risks and rewards of running glycol through our precious system.

All this plumbing appears to have paid off. Our CCD39 read noise is down to 4.1 electrons, and we can read our CCD47 (the VisAO science camera) full-frame with 4.5 electrons – and maybe lower depending on ambient temperature. The cooling system helps us achieve these numbers because it keeps dark current low. The CCD 39 having low RON helps us work on faint guide stars, especially important for Clio2 (in case you missed it, Katie posted an update on Clio2’s progress towards shipping here).

It wasn’t all work today.

We've been in the hands of Hector and Jose on this turno. The food is awesome.

Today’s quote: “I can imagine the feeling.” (Alan Uomoto)

And speaking of Alan, I know at least two things about him. He reads this blog, and he cares. So much so that he went out of his way to make sure that Marcia Males has a poop-free picture of her son.

Thanks to Alan and some windex, the bird poop is gone.

And on my way down for supper, I had a close encounter with the VisAO mascot. He’s getting to know me I think.

Days without a motherboard failure: 4

NAS Fitcheck Day 4: Head in the clouds

This morning we woke up to this:

This light dusting was the most we got, though it spit throughout the day as the clouds rolled through.

We’re here for a reason – to find out what doesn’t work so we can fix it before the real deal happens in November. Today’s discovery was that the planned route for our cable wrap through the Nasymyth platform deck won’t work. Our instrument has to rotate to track the sky through the night, which means our power, data, and cooling lines all have to rotate with it. So we need a cable wrap to manage them as they get longer and shorter. Tyson and Jason are busy sketching out plan B.

Tyson on the catwalk under the Nasmyth platform, looking for a good place to cut a hole.

Speaking of cables, the staff has been running new network fiber for us. Our system moves lots of 1s and 0s every second, so we have our own networks to handle it all.

Emilio working in the tunnel under Clay.

The observatory was inside a cloud for most of the day. We frequently couldn’t see the next building over.

The Baade from just down the boardwalk.

Tonight’s quote: “Ok, whoosh is maybe a strong term. More like swish.” (Laird Close, discussing rotator speeds and decapitation)

Lunch was a good cold and foggy selection.
Before my mom starts complaining, here's me. The bird poop is still there.
It was starting to clear by dinner. Alan got a nice sunset shot.
One of the last wisps of clouds.

Days without a motherboard failure: 3

Interlude: Installing new cold stops and a J-band filter into Clio2

Meanwhile, back in Tucson… We interrupt the NAS Fitcheck program to bring you this update on the Clio2 infrared camera.

After the Pre-Ship Review for Clio2 in Amsterdam in July, we have been completing preparations to receive diffraction-limited near-IR to thermal-IR photons from MagAO. Yesterday and today we installed the new J-band filter, and the cold pupil stops sized for Magellan. This was done in a CAAO lab at Steward Observatory in Tucson, where Clio2 is undergoing its final testing before shipment.

Cold pupil stops: Clio2 used to be “Clio” and was installed on the MMT telescope in Arizona. The MMT, like Magellan, is a 6.5-m telescope, but the Magellan secondary is 0.85m while the MMT secondary is 0.7m. Therefore, because the pupil is different, we needed two new cold stops for Clio2 on Magellan. A cold stop is a cryogenically-cooled metal mask located at an image of the telescope pupil, and its purpose is to block stray light (heat sources in the dome cause a lot of background thermal light) from contaminating the infrared image. Here is a picture of the pupil wheel with the new cold stops:

Clockwise from Phil's hand: 3-hole non-redundant aperture mask (NRM); 6-hole non-redundant aperture mask (NRM); Wide-camera cold stop (home); M-band apodized-phase plate (APP); L'-band apodized-phase plate (APP); Narrow-camera cold stop.

We also added a new J-band filter, taking out the old 3-5um Janostech filter from filter-wheel 1:

Clockwise from the red arrow: J (new), Blocked (for darks), Open (home), MKO M', Barr M, Direct vision prism, 3.1um, Barr L'.

We updated the Clio2 user manual at http://zero.as.arizona.edu/groups/clio2usermanual/ so that we can repeat this in Chile if need be.  Note the tools required: Most of the wrenches were found in a standard set of Allen keys, except for the 0.035” driver which is a special size.

Tools required for changing Clio2 filters: Phillips/flat head, 0.035, 5/64, 3/32, 7/64, and 9/64 inch Allen keys.

It took about 3 hours to take it apart and insert the new filter and pupil stops, including finding new spacers, etc.  It took about 1 hour to put it all back together.

 

T.J. Rodigas (foreground) and Andy Skemer (background) helped take Clio2 apart.
The box labeled 3 and 4 contains filter wheels 1 and 2. The box labeled 2 contains the cold pupil stops. We disconnected the wires and unscrewed the bellows (those keep the shafts straight at cryo temperatures) to access the filter and pupil wheels.
The same view as the previous image, with the filter and pupil wheels removed.
Two by two, hands of blue
Opening the pupil box to put in the new cold stops, and also Phil put in a new home switch. (Otherwise we could have just inserted the new cold stops through the port and not had to open it all the way.)
Oli Durney putting Clio2 back together

 

NAS Fitcheck Day 3: Cold, Pressurized, and Telecentric

The weather has taken a turn for the worse at LCO. It is currently 1.8C and blowing at 32.7 mph. And getting colder.

Speaking of cold, we installed the new liquid cooling system in the W-Unit today.

Jared and Laird installing the brass cold-plates on our CCDs.
Jason getting ready to install the shutter. Jason first assembled the shutter heatsink and mounting system nearly 2 years ago.
Jared checking the shutter mounting. It is a tight fit, and we don't want any metal-metal contact because the shutter vibrates. A lot.
The team at work on the NAS, under appropriate supervision.
The finished product.
The test gauge for the CCD cooling system.

The other big accomplishment in world of the NAS today was Laird installing the Telecentric Lens. This almost flat lens lets us work off-axis, away from the guide star.

The new telecentric lens.
View past the cube, through the new telecentric lens. That's L1 there.
After installing new glass, we checked the system. Everything looks great - the wavefront is flat and our i' PSF is 3.2 pixels. Click for more pixels.

We also got some time in the dome, and did a little work on the Clay telescope. The vane-end trays are installed, and the leak preventing solenoid valve was plumbed and tested.

Jason and Juan working on the solenoid.
Installing the vane end trays.

This hawk was hanging out over the observatory at lunch today.

A hawk over Magellan. Click for full wingspan.

Tonight’s pretty pictures are from Alan Uomoto, who spent some time messing with his camera’s settings today.

The beginning of the weather. Note the top of the fog in the valley below. Click for bigger.
A panoramic view of the hotel and Las Campanas itself. Click for more awesome.

Days without a motherboard failure: 2