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2014_10_0405

Weather

This is the first evening of real autumn!  Today was partly cloudy and fairly warm, maybe 75F – but tonight the temperatures are rapidly dropping and it is quite windy.  The low tonight should be in the mid-upper 40s.  At the beginning of the evening the seeing was just slightly better than two arcseconds, but now (9:55pm) it is worse than 3 arcseconds.  Very clear but very unsteady air.  UPDATE – around 10:00pm the seeing started to improve markedly – to around 2 arcseconds.  UPDATE – by 10:30pm the seeing had again gone to around 3 arcseconds!

Targets

Rig #1 is running another sequence of spectra for the U Montreal campaign – Deneb and PCyg, both at H-alpha, then Deneb at the Si lines.  Rig #2 is again shooting a sequence of images of GD552.  This may be my last night on this object as Joe Patterson is requesting data from several other targets.

Software

There have been several nights of good observing for which I’ve not kelp a log.  I’ve also been working on squashing bugs in the PPX program (previously PhotProc-X).  I found a bug in the PPX code that caused signal-to-noise to be very much under estimated.  It had to do with the way the weighting mask was being built and resulted, in fact, in the mask becoming almost a straight aperture photometry mask with softer edges.  After fixing the bug photometry of the typically fainter program objects improved markedly while the standard deviation of comparison star light curves increased somewhat.   Other software such as Maxim and Mira both show lower standard deviations in comparison-minus-check light curves, but PPX’s curves for fainter program objects is clearly “tighter”.  That is to be expected as the weighting mask is optimized for the program object and not the (in this case much brighter) comparison stars.

I also had some problems with the star matching program MATCH_STARS.  Once I had fixed the PPX bug I went back and re-reduced all of the data I had for GD552 over the past four years.  The data I’d acquired in 2011 had been taken using the ST9 camera and on a couple of the nights following meridian flip there was not much overlap between the template and the flipped images.  I re-wrote the main loop to allow the program, if it could not get a good set of matched stars, to go back and add another star and re-run the analysis.  The user can choose how many iterations are run before it gives up and returns zeros for every one of the fit coefficients.  There was also a small bug that caused the program not to properly order the triangle vertices with their corresponding opposite sides.  It wasn’t a huge problem but the program now is much more likely to find matched triangles when there are few overlapping stars.  Finally, once a good fit is found, all of the stars sent to MATCH_STARS are then fit which greatly increases the number of stars used to create the final transformation coefficients, the hope being that the transforms thus derived come from a larger overlap area than they might given just a few bright stars.  Changes in the resulting photometry, thus far, have been small to none.

LHiRes III

I’m beginning to have some suspicions regarding how stable the grating micrometer is.  For the U Montreal campaign I have to change the grating angle twice during the night.  What I think I’ve noticed is that following a change in grating angle it might take a few minutes for things to “settle” – I think I’ve seen the lines move very slightly between two comparison spectra taken only a minute apart.  This is something I can easily check – maybe tonight after the final program spectrum.

 

Out at 1:45 am – nice night – the first night that it’s felt like autumn!

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2014_09_0304

Rig 1

Another set of spectra for the BRITE/UMontreal campaign on P Cyg and Deneb.  I am seriously behind in getting these data calibrated and sent.  Something for the next few days as the clear weather is supposed to go away for a while.

Rig 2

I monitored a new (for me) object tonight at the behest of one of the CBA members (Enrico).  J010742.6+484519, an eclipsing system with 2.5-magnitude eclipses.  Here’s a plot from last night’s data:

All in all everything worked pretty well – the “real” magnitude scale here would be about +13.0 from what is shown (the comparison star’s V magnitude is 13.0).  The standard deviation in the comparison star light curve (in blue) is only slightly above 0.005 magnitudes.  Sadly I had to throw out a fair number of exposures as there were some serious issues with the tracking in declination, ruining dozens of frames when the telescope would “jump” in declination, causing double images.

2014_09_0304

 

Declination Gear Stiction

The problem can be seen in plots from the autoguider logs.  The image, below, shows both before and after.  Basically the problem turned out to be stiction due to the declination worm being too tight against its gear.  Note that during guiding I had the declination motor making corrections in only one direction (southward).  The mount is not yet perfectly polar aligned and so drifts slowly to the north.  This is something I intentionally did for the CGE mounts but in this case it’s just me not having enough time to really get the azimuth adjustment right.  Anyway, in the top frame what you’re seeing is the slow drift of the guide star’s position as measured in each 4-second guide camera exposure.  As the object crosses the zero line the motor should (and did) engage to make the correction to return the star to its initial position on the chip.  But the gearing was so tight it would not move until a lot of “spring” tension had built up in the gearing and then would “snap” – and since it had not moved as commanded during all the previous corrections the result was a massive over correction.  Then the entire sequence would repeat.  The bottom panel shows the guiding after loosening the pressure between worm and wheel.  There is still a slight bit of the same phenomenon occurring, at a much smaller scale.  Earlier today (writing this on 4-September) I loosened the worm and gear a bit more and added a touch of lithium grease to the spur gear assembly.  In the next week or two I’ll be taking both of the motor assemblies off to clean and re-grease the main worms and gears.

 

Autoguider3

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2014_08_2526

August 17/18 – First Night for AP1200 in the North Dome

The photometric rig in the North Dome on its new ride.

The photometric rig in the North Dome on its new ride.

No entries here for two nights past.  The first was the night of August 17/18.  On that night I was able to get a full set of spectra for the UMontreal BRITE campaign on Deneb & P-Cyg.  More significantly, however, it was the first night of observing using the new AP1200 mount in the north dome.  A couple of things were obvious.  First of all the pointing is dead-on.  After a 12-star MaxPoint solution using stars both east and west of the meridian, but with the telescope always west of the counterweights (using the AP “meridian delay” feature) the mount puts most targets within the central half of the chip, usually closer.  The other thing is that it does not track well in declination.   Looking at the guide logs it appears to me that there might be a bit of stiction due to the dec worm being too tight against the wheel.  I will likely loosen that just a bit to see if it solves the problem.  The symptom is that as the star begins to drift away from center the mount is being sent commands to make corrections – which don’t seem to show up.  But then it jumps, in the direction it needed to move, but typically by half again as much as necessary.  Pretty typical of stiction problems.  The other thing I may do, which I did with the other 1200, is to clean and re-grease everything.  The 1200 in the south dome, despite its early troubles, guides very smoothly.  Note that it does have a small amount of backlash in declination and that the worm on the declination could be tighter against the wheel.  Here’s the night’s data.  At magnitude 16.5 this object is near the limit of what I can expect to do here in the soup.

2014_08_1718
Note the sudden half-magnitude jump and return to “normal over the course of around 30 minutes.  If it stays clear tonight I may revisit this one.  I’ve got data on GD522 from 2010 and 2011 as well and have seen jumps like that before.  It was a night of really amazing seeing, likely near 1 arcsecond.  It is interesting that, while having lots of cloudy weather this summer when it has been clear the seeing has been better than normal.

August 24/25 – Dodging the Clouds

Last night was an exercise in dodging periods of cloudiness.  So on the photometric side I only got a few hour stretch on AO Psc, and on the spectroscopic side I just barely squeaked in a full set of spectra.

Software Headaches

I really don’t know why I do this to myself.  I’m totally inept in a unix-like environment.  But last weekend I got this irrational desire to try to update the virtual machine I use which came to me via Dr. John Beaver at U Wisconsin-Fox Valley.  Called VARMiNT, it is a complete set of astronomy software pre-loaded on a hard disk which can be run using the VMWare Virtual Machine Player.  It is loaded with Ubuntu 12.04, IRAF 2.14, PyRAF, SciPy, NumPy, Python 2.7, lots and lots of other stuff.  But hey, there was a newer version of IRAF, the Space Telexcope Institute had this thing called STScI-Python which included up-do-date versions of IRAF, PyRAF, Python and all the rest, and a new version of Ubuntu – 14.04LTS.  I had already tried to simply run all the Ubuntu updates for VARMiNT, but it screwed up the display.  I tried it several times, each time re-installing the VMWare Tools, to no avail.  So I decided to start clean to try to create a “VARMiNT 2.0”.  Did I say I’m unix illiterate?  Well, amazingly I managed to get a working virtual machine with Ubuntu 14.04, IRAF 2.16.1, and have downloaded and supposedly installed STScI-Python.  But being the Unidiot I am I can’t even figure out how to get a PyRAF prompt!   I do seem to have Python 3.4 installed and running (as well as 2.7, which I think came with Ubuntu).  It looks like I’ll be learning another programming language.  Just bought a Python programming book.  Oh joy!

 

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2014_08_1314

Weather

Well, after yesterday’s 7+ inches of rain …. Tonight is fairly clear (still slowly improving from the smoke haze).  I could actually see second and third magnitude stars even after moonrise.  Good seeing – around 1.8 arcsec.  Very little wind, low tonight expected around 60F.

Targets

  • Rig 1:  More data for the BRIGHT campaign on P Cyg and Deneb.  What I’m doing each night is to get one time through the requested sequence, then I take two more sets of P Cyg spectra at H-alpha – separated an hour from one-another.  Then the final set of spectra are of Deneb dialed in for the Si lines.  I’m getting pretty far behind on reducing the spectral data ….
  • Rig 2:  ASASSN 13ae – or J174033.4+414756.  Joe Patterson requested data on this object which just went into outburst a few days ago.  It’s pretty bright, shot a sequence of 30-sec images, until the maple tree got in the way.  That was at about 1:15am.

 

Last night using the CGE?

The pier adapter plate should arrive tomorrow sometime – if it is clear tomorrow night I’ll stick with the CGE one more night, otherwise the new AP1200 is going to be moved into the north dome.

PhotProc_X

I finally published the paper about PhotProc_X – the name I’m currently using for the variance-weighted optimal extraction photometry program.  At one point yesterday I pulled the article as MaxIm DL’s photometry task kicked it’s tail reducing some of the data from the past week or so.  Again, it appears that PPX is very sensitive to changing PSF shapes.  It turned out the biggest difference occurred at meridian flip – similar to one of the cases mentioned in the article.  Overall scatter is less with PPX, but especially at meridian flip the PPX data has a much larger “jump” in the differential magnitude curve for a pair of “standard” stars.  I’m really hoping the new mount will help, as I won’t have to do a meridian flip for at least three hours after meridian passage, which usually puts objects into the tree anyway.  I really need to figure a way to flatten the field better.  Or get a new telescope for photometric imaging.  I may see if I can get someone who owns one of the new AT Ritchey-Chretien ‘scopes to take a few pictures for me – I’ll measure them and see if they’re an improvement over the C14.  I’m guessing they are – but I’m also guessing they’ll still present problems.  The new AT 20-inch RC sure is a tempting target!

Out at 2:00am – my knee is killing me from a long day of work and play.  Time for ice and some rest.

 

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2014_08_1011

Wow – two clear nights in a row.  About the best stretch of the entire summer so far, testament to how bad this summer has been.  In fact the past 18 months or so has been much more cloudy than I can recall (other than when I used to live in Michigan).

Weather

About 70F, no wind, steady (about 1.6 arcsec seeing) and still slowly clearing from the forest fire smoke.  Full moon tonight – looks more clear than last night.

Targets

  • Rig 1: Deneb and P Cyg.  Took four sets of P Cyg data at H-alpha – roughly separated an hour apart.  Took two sets of Deneb at Si lines – about four hours apart.
  • Rig 2: RX 2133+51 – 220 90-second images!

Software

After weeks of fighting with issues with the newest version of Mira (Mira Pro 8eUE – beta 5, released on August 6th) I’ve finally gotten it to work.  Mike Newberry obviously has tweaked a few things and fixed a few of the bugs found, but it appears some of the problems may be due to access restrictions in Windows 7.  I originally contacted Mike when I could not get Mira 7 UE (7.974) to save calibration parameter sets/profiles.  In fact, following a Windows 7 automatic update sometime in mid-July, the program would not save any parameters from forms/dialogs, etc.  So at the time Mike suggested I upgrade to the new version, so I bought a license renewal which will also give me Mira 9 UE when it appears (later this year?).  Anyway, lots of Mira 8 just did not work.  Way too much to list here, but it was basically unusable.  But following a new Beta release (beta5) most of the problems seemed solved, but I could not get it to see scripts from the script manager dialog.  For whatever reason, after using some scripts in Mira 7, I went back to Mira 8 and there were all the scripts!  Very strange.  The only thing I can point to that I changed was that I changed the permission in C:\Users\Mike so that it was not “Read-Only”.  Pretty simple fix if that’s all it was.  It’s great having Mira back as I really do depend on it and dreaded the thought of trying to create something on my own that would fulfill the tasks I use it for!  There are still some things that are very flaky – particularly how it saves (or does not save) default behavior of things like default image display parameters.  But Mira UE8 is looking really good right now – I really like the improvements in the UI.

 

 

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2014_08_0910

Weather

For most of the past week it’s been pretty “clear” – that is, fairly cloudless and cool.  But large wildfires in the Canadian NWT have spread smoke into the upper atmosphere that has hazed out the entire east coast over the past week.  You could see that beginning to move off during the day today and tonight, while not totally gone it is much reduced.  Some other bits of cloud remain, otherwise a very nice night.  about 70F, no wind, VERY good seeing, around 1.5 arcsec.

Rig #1:  Spectra for the U Montreal P_Cyg/Deneb campaign

View of the control panel for Rig #1 tonight - gathering spectra of P Cyg and Deneb for Noel Richardson at U Montreal.

View of the control panel for Rig #1 tonight – gathering spectra of P Cyg and Deneb for Noel Richardson at U Montreal.

 

Rig #2: RX2133+51

I decided to go for another night on this object – it is fairly bright and is far enough away from the full moon that I should be able to get some good data. Sky haze was also a consideration, though it is much less a problem tonight than it has been.

Control panel from rig #2 showing on-going sequence for RX2133+51 (near edge of blue circular "aperture").  Note the FWHM shown in the "Information" dialog - about 1.7 arcseconds - and that includes guiding errors.  So a night of extraordinary seeing.

Control panel from rig #2 showing on-going sequence for RX2133+51 (near edge of blue circular “aperture”). Note the FWHM shown in the “Information” dialog – about 1.7 arcseconds – and that includes guiding errors. So a night of extraordinary seeing.

 

Installed A Wifi Range Extender for the Domes

Since getting Comcast  installed at the studio I had an extra range extender available and so I’ve installed it in the South Dome, and run ethernet cables to each laptop.  In fact, since cladding the outer surface of the north dome the laptop inside has had a hard time getting any level of wifi signal at all.  Usually I would have to rotate the dome so that the slot was facing the house, sync the clock to NIST, then go on about the night, checking back a few times an evening to keep the computer clock within 1 second of universal time.  It also made it next to impossible to run Remote Desktop to control things from my study.  Things are MUCH faster now.  I decided to turn off the wifi radios on each laptop and ran cables from the repeater, making the repeater the only communication link with the house. It’s working much faster than either laptop did individually so this is a real improvements!

CGE Countdown

I got word from Dan Harman (he of Dan’s Piertop Plates) that he expects the adapter plate for the AP1200 back from anodizing on Monday and that I should have it by the end of next week.  So if all goes well the CGE mount in the north dome, which has served so admirably for eight and a half years,  has a life expectancy numbered in single digit days.  For all the crap I read about this mount (which indeed does have some frustrating problems) the two CGEs that have been used here have both been pretty darn good.  As an example, tonight’s tracking is better than +/- 0.3 arcseconds.  Sure, the target is at +51 declination, so that reduces the RA tracking errors by about 40%.   The CGE mounts sell for around $1500 in pristine condition (which mine aren’t).  Quite a bargain!

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2014_07_3031

Weather

Cool and dry, which would typically also mean quite clear.  But there are massive forest fires in the Canadian NWT that are sending smoke high into the atmosphere and causing an over-all haze that has stretched from the mid-west all the way to the Atlantic.  The sky tonight is about as hazy as it might be for a typical summer evening, while the temps (predicted lows in the low 60s) are like early September.  Seeing is good.

UPDATE  – seeing is really good tonight.  Last few images of RX2133+51 had FWHM of about 1.8 arcsec – and that includes all the guiding error in 90-second exposures.  So the real seeing is actually much better, likely 1.5-arcseconds or less.

Targets

The South Dome telescope is taking spectra for the BRITE/Deneb campaign.  Starting tonight I’m monitoring RX2133+51 for the CBA.  It’s just bright enough to get good S/N (showing around 60 right now) in a 90-second exposure.  As the moon waxes towards first quarter it will be interesting to see (assuming this smoke haze remains) how the sky levels increase.

Software: PhotProc_X

So I finally have gotten PhotProc_X to work on my laptop – basically the first time I’ve tried running the IDL Virtual Machine.  It works fine – but the lack of any sort of command prompt meant I had to create a widget for parameter input, and some sort of visual indication of what the program is doing.  So at the current time it just uses a text widget to display where it is in the program and presents a message when completed.  I’m going to add a log file to the output; if the program crashes messages will be found there and a message will be brought up on the screen.  Since all these messages are presented in modal dialogs and thus block any interaction with the text widget used for output it makes little sense to have the text widget display more than just very basic “what I’m up to now” info.  The log file can save all the rest.  Other than that the program has been much cleaned and improved over the past few weeks.  With a few more tweaks to come – like making some of the image match input parameters visible – ability to save program startup parameters (part of both the log file and the csv file) among them.

Software: Mira 8.0

I re-upped support for Mira – and have installed Mira 8.0.  It has lots of smaller bugs, mostly just annoying.  But the UI can hang easily if there are lots of images loaded and one tries to use the slider to move quickly through the image stack.  M Newberry is working on them – but it sounds like the totally new Mira – versio 9, which will be fully 64-bit, might be just ’round the corner so I’ve volunteered to help Beta test.  Oh joy!

 In Praise of the CGE

The CGE in the North Dome is working really well, almost like it is trying to make me re-think replacing it.  Tracking tonight (great seeing, object at +50 degrees declination, nice bright guide star with 1-second exposure time) is around 0.7 arcsec in RA and 0.4 arcsec in declination.

CLOUDS!

I had to know it was too good to be true.  I finished up with the spectroscopy for the evening around 1:00am, closed up the dome, but continued the sequence on RX2133+51 from the North Dome.  Meridian crossing was around 2:00am – when I went out to the scope the skies were covered with clouds!  Oh well, maybe get some sleep (wrong or not!)

 

 

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2014_07_1718

Weather

A truly spectacular evening!  Great transparency and seeing is around 1.6 arcsec.  Low temp in the upper 50s, low humidity, and no wind.

Rig 1 / South Dome

Another sequence for the BRITE campaign – P Cyg and Deneb.  Also getting a series H-alpha region spectra of Nova Cygnii 2014.

Rig 2 / North Dome

Started with DQ Her but made so many mistakes getting set up that I just “hit reset” and decided instead to do V2069 Cyg.  The pier plate for the new AP1200 can’t come soon enough!

AP Hand Controllers Updated

I downloaded and installed the latest hand controller software (V4.17) and installed on both of the units.  I had a lot of trouble with the older hand controller – it kept clicking off and on every time I tried to press buttons to enter data.  It often seemed to loose power and switches off and back on – something I’ve noticed ever since starting to use it last summer.  So today I took it apart, disconnected all the internal connectors and cleaned them with alcohol.  It now seems to work just fine.  I was really worried it was fried – $1300 saved!

Done at around 4:20 AM – EASILY THE BEST NIGHT IN A YEAR!  Out of gas and knee is in some pain or I’d have gone until sunrise.

 

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2014_07_1617

Despite feeling really awful I just could not let the first decent night in two weeks go unused!  I only opened the South Dome – ran a sequence for the BRITE project (P Cyg / Deneb).  While “clear” the transparency was not great.  Slowly drying out after a long wet and humid spell.  Low tonight around 62F, no wind.  I finished the entire sequence by just after midnight – closed the dome and headed inside.  A very vigorous PT session today has me aching so I need some rest.  Six weeks after total knee replacement – doing very well overall but just not tonight.

New Counterweight Shafts / Measuring Mount Height

I got two new, shorter counterweight shafts for the two AP1200 mounts.  I was a bit concerned I’d need more mass on the spectrographic rig in the South Dome, but turned out not to be a problem.  Also I measured the height of the AP1200 mount in the South Dome to determine how much higher the telescope would “ride” as compared with the CGE mount.  The North Dome, where the newer AP1200 will soon be installed, is only an 8-foot dome, and the telescope with its dew shield only barely misses the inner dome ribs when slewing, so it’s an important consideration.  But it appears that the AP1200 is actually about a half inch shorter than the CGE as measured from the bottom of the pier base plate to where the telescope sits above the declination shaft.  That’s a good thing since it otherwise would have meant building a small ring to raise the dome a few inches.  So that certainly counts as good news!

Software Development

I’ve spent a lot of time over the past week improving photproc_X – the optimal extraction photometry tool.  It turned out there were a couple of subtle bugs in the actual variance weighting part of the code, which now should be working properly.  I’m preparing an article describing photproc_X with some comparisons to other multi-image photometry software – AIP4WIN, Maxim, DAOPHOT’s aperture photometry routine, MIRA, and Canopus will likely all be included.

 

 

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2014_07_0405

Weather

While fireworks go off all around me – it’s a perfect summer night.  Low tonight around 60F – very clear.  Hurricane Albert passed off the coast earlier today taking the clouds with it!  Seeing is around 2 arcsec at beginning of night.

Targets

Rig 1:  BRITE campaign – P Cyg and Deneb

Set up the following cadence:

  1. Zeta Aql   6532
  2. P Cyg 6532
  3. Deneb 6532
  4. Deneb 6334
  5. Zeta Aql 6334
  6. Zeta Aql 6532
  7. P Cyg 6532 > repeat w/ occasional visits to Zeta Aql.

I need to find out from Noel what he means by several images of P Cyg – I’ll just run a sequence at the end of the night for now.  But he’s interested in monitoring H-alpha changes at several time scales – even 5-minute time scales?

 

 

Rig 2:  WX UMa

Likely the last night on this object – it’s just getting into the trees too early, the longest run I can do is now around 4 hours and there are more compelling targets in the east!

Photproc Issues

The other day I tried reducing a nights’ data using AIP4WIN – and it produced better results than photproc!  So I’ve revisited the optimal extraction part as that appears to be where the problem is.  In fact, if I use DAOPHOT’s “APER” task it gets quite close to AIP4WIN’s results, so there is definitely something wrong.  Optimal extraction should be able to do a better job than either as both are simple unweighted apertures.

Bailing early!

My knee is killing me!  32 days after knee replacement, not feeling too badly over all, but took a fairly long walk today and the knee is really sore – so stooping to get into and out of the domes is not something I want to do much more of tonight.  Out at 1:30am.  I noticed small crescents of dew on each telescope.

Another AP1200?

Several are for sale on AstroMart right now.  I’ve contacted two of the sellers, one in NC, the other in NY.  I’d love to replace the CGE in the north dome…..

UPDATE: See This