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6/3/2014:

 

September: paper titled "Dynamic real-time scheduling of optical systems"
   - Write down merit functions 
   - 5 sigma zero point magnitude of stars
   - Include seeing model

Field FOM x SSM x DSM = IFM
Field FOM is a function of time
SSM is static airmass associated term (everything computable in advance)
DSM is sky brightness and clouds and like
Issues:
   - NCSA disk
   - Photometric scatter
   - Photometric transfer equations
      - Transform from our R,G,B to G,R,I,Z,Y (stars on Wiki can be used to generate )
   - Internal Reference Catalog
   - Deliverables
      - Convert FITs files to healpix
      - To observatories in real time (web server with FITs image and contour map with RA/Dec lines laid on top)
      - LSST simulation guys
   - Tier in to IR All Sky Camera
   - Dome flat
   - Sky flat
      - Making Reference catalog
   - Correction to LSST sky
      - Stelar density dependent correction to sky brightness because LSST can resolve many of the stars that we cannot
      - Pixel and time dependent
   - Sky brightness model
   - Jacobians
      - Check assumption that the solid angle subtended per pixel is same across entire image
      - Take white teflon sheet behind point source and rotate lens and ask if the number of counts per pixel insensitive to rotation info of lens

Opport:
   - Daytime contrails
   - Real-time to SOAR and Gemini
   - Calibrated sky brightness w/ PD's
   - Dome free sky obs to calibrate dome scatter
   - New dome?
   - Overall plan for calibration + schedule

   - DES tie-in

 

Michael to-do for scatter:

Excess noise (non-Gaussian)
   - take darks in lab
bad pixels
   - subtract pair of darks
aperture contaminated
   - plot dm vs. dx,dy

diagnostics:
   - m vs. t, chi^2 vs. mag
   - m_i vs m_j, m_R vs m_G, ...
   - residuals vs. dx, dy
   - resid vs dm
   - resid vs chi/N

   - compare short exposures

 

05/30/2014:

  1. Talk with Andy to figure out what output they want
  2. Convert pixels to RA, Dec for each image and then add it all together. Use to make a template and search for transients. 
  3. Things to fix / look at: secant, stars that have magnitude issues (look constant)
  4. Make the deltax, deltay plots

05/29/2014:

Attendees: Michael and Chuck

1. Create a public fits files directory

2. [coughlin@lsst-dev ~]$ pwd
/lsst/home/coughlin

# User specific environment and startup programs

PATH=$PATH:$HOME/bin
PATH=$PATH:$HOME/allsky/bin
PATH=$PATH:$HOME/wcstools-3.8.7/bin
PATH=$PATH:$HOME/fisheye
PATH=$PATH:$HOME/sextractor-2.19.5/bin
PATH=$PATH:$HOME/tphot
PATH=$PATH:$HOME/tonrytools
PATH=$PATH:$HOME/ffmpeg
PATH=$PATH:$HOME/ImageMagick-6.8.9-0/bin
PATH=$PATH:$HOME/cfitsio

https://github.com/mcoughlin/fisheye.git

3. Create master catalog for all stars by looking at photometry over all the nights
   - Then will not have to recreate mapping for each night
   - TODO: Michael and Jamie
   - CS: There are existing catalogs of stars, for example the paper I sent you with bright stars and their griz-band magnitudes. It's better to get an external catalog
with excellent astrometry than to make our own, I think. 

4. Abi (dophot) can fit individual images to extract magnitudes (compare with tphot/source extractor)

5. Search for transients with image subtraction (pixel by pixel image difference)
   -> Convert (x,y) to RA/Dec (w/ fisheye)
   - CS: Converting to RA, DEC is not enough. We'd have to rotate the images about the celestial pole, match PSF and sky, and then subtract.
Sounds hard.
6. For a given star, plot the magnitude differences vs fractional pixel remainder of the centroid (1024.35 -> 0.35) -> probably worst for R/B due to 1 pixel, different for x and y
 

7. Can see milky way in cloud plots -> problem with sky brightness in photometry. Fix!

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