Nightlog 2011-04-05

SA: David
SO: Siphelo
Others: Lisa, Paul, Ken (Dave C. & James for a bit)

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Summary
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Excellent stable night, but seeing unspectacluar.

Working with subset of SALTICAM filters, with no problems.

Continued characterising autoguider/autofocuser performance.

Tested slotmode.

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Big day coming up tomorrow...

SALTICAM's been giving us a hard time - first the filter system started playing up & then the CCD controller developed problems.  Much frustration, but Dave C & James came up from Cape Town yesterday so they're on the case.  The Tarantino feel to the image below is merely due to saturation - but it sort-of conveys the mood!

The good news though is that RSS is ready to go up tomorrow!  So the baffling's been removed from the top of the payload & the new kinematic mounts are in place at the 1, 5 & 9 o'clock positions on the rho ring.

The spectrograph's other attachment points around the ring will get finger-tight bolts through these plates to ensure that nothing can escape.

Over in the circular, black room, Peter did some final testing & light baffling on his friend...

David, Siphelo & Paul were at the helm this evening & decided to get some sky flats - offering this dramatic view of the telescope from the road below.

& what a magical twilight it was - crepuscular rays blasting up from the razor-sharp western horizon...

& an impossibly thin sliver of moon sinking into the rich orange glow.  Ted Williams' enthusiastic words at the last SALT Board dinner, along the lines of it being about to get dark up at SALT, perfectly capture the sense of excitement & expectation as we approach another huge milestone...

Nightlog 2011-04-04

SA: David
SO: Siphelo
Others: Lisa, Hitesh (Dave C., James & Ken for a bit)

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Summary
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Excellent night, although SE wind, so seeing mediocre (~2").

SALTICAM SDSU brought back to life in the afternoon, but filter problems
remain. So stuck to V filter all night.

SALTICAM images with pellicle obtained. Images a little degraded (1.7 ->
2.2"), but were round and useful. Should be fine for bright stars, as
was intended.

More successful closed loop guidance tests on fainter stars.

Test of FT mode.

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Nightlog 2011-04-03

SA: David
SO: Siphelo
Others: Lisa, Hitesh

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Summary
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Two major faults with SALTICAM:
1. filters can't be changed reliably (gripper errors)
2. SDSU faulty and all CCD frames (incl. biases) are saturated.
The latter precluded any observations for the night, unfortunately.

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Closed loop tracking & focus control, & Ouberg Pass

The past few nights have been about checking out SALTICAM's functionality & making sure that the software does all it's supposed to.  This has kept Janus & Luis rather busy & the Astronomer Hat's been oscillating between David & Darragh.

Sadly, there's been some mechanical damage to one of the guide probes & so it's not able to operate over its full envelope - this will have to be repaired at a later stage.  In the meantime though, it's been possible to move the tracker in order to get a star onto the probe & then to proceed with commissioning the SALTICAM guidance & autofocus systems.

This led to full closed-loop tracking for the first time - a major milestone in the telescope's progress to full operations!  Fantastic work Janus :)

Various other software functions for getting targets placed - such as offsetting &/or rotating the field to put an object onto the RSS slit or into the slot for high speed work got ironed out by Luis - seen here enjoying the power hat... 

The new slot in the SALTICAM frame transfer mask really is a huge improvement over the old one which was positioned too high above the CCDs - mooi so Willie!  The slot's visible across the centre of the field & the profile in the top left corner shows a cut across the slot.  The red outline represents the position of the guide probe.

On a very different note - the Saturday morning mission centred on Keith's ambition to cycle down, & then back up, the Ouberg Pass.  This is the spectacular edge of the escarpment, about 35 km from Sutherland, that drops about 600 m over less than 7 km.

It was a perfect day out there, particularly enjoyable if you didn't have a bicycle to worry about & absolutely wonderful if photography's your thing... 

Here's the downhill data from the lunatic's GPS & heart-rate monitor - note the red (heart rate) peak immediately prior to the blue (speed) dip when a tricky corner (pale green spike) came up!

To everyone's astonishment, he made it in one piece & actually did cycle all the way back up, the round trip taking an hour & 40 minutes (10 minutes of which was the downhill!).  The captain of the support team was on hand to administer the necessary refreshments back up at the top...

The data from the ride up tell the rest of the story - the things some people do for fun?!

Nightlog 2011-04-02

SA: David
SO: Siphelo
Others: Darragh, Luis, Janus, Lisa & Martin for a bit - until he was

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Summary
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Success with SALTICAM closed loop guidance & focus, despite hobbled phi
motion.

All SALTICAM tel. offsets successfully tested (random, to RSS slit, to
SALTICAM slot, translation & rotation).

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Nightlog 2011-03-31

SA: David (wearing the astronomers hat)
SO: Siphelo
Others: Darragh, Luis, Janus, Lisa, Charl, Chris

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Summary
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First successful closed loop guidance and autofocus with SALTICAM guider!

Conditions were challenging: huge temp drop, high humidity throughout
the night.

Stray light tests done with closed dome later on.

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