July 9th, 2009
IDL Method******************************************************************************** You will need to programs called 'make_calinfo.pro' and 'broadcalv2.pro' located at: /d/users/davec/programs/ ******************************************************************************** *make a directory and put all calibration images in this directory (I usually name the directory 'MonthDayDayYear') *get a file called landolts.dat from: /d/users/davec/clusters/data/calibration/landolt/ *put 'landolts.dat' in the directory above the 'MonthDayDayYear' directory you just created. *make a text file (called notes.txt; make_calinfo.pro only recognizes this name) and put this file in the 'MonthDayDayYear' directory. This file will contain notes that you will write about the photometry of each standard star image and the order of the stars that was photometred. It should look like this: file ,field (landolt name), landolt star name: ************************** a0009,92,259,342,339,335 ************************** for PG#### standard stars it should look like this: ************************** a0055,PG0918+029,1,A,B,C,D ************************** ***Common Landolt fields are SA###_### or PG####+#### SA field name is the first numbers before the underscore (2 or 3 digits) and the star names are the numbers after the underscore. PG field names are the first 7 numbers then the star names are the last letter (ex. PG1633+099A; field name = 1633+099, star number = A). display the images and load the regions for the particular field you are calibrating regions can be found at /pawnee3/davec/clusters/data/calibration/regions). Before doing any photometry make sure you check which stars are going to be useable for each pointing: 1)Make sure that you are not using stars with fewer observations than 3 (at the very least!!!) I use n = 4. AKA get rid of any stars that have been observed only 3 times or less (see landolt paper). 2)Run IMEXAMINE on all images and hit 'r' on each star to make sure there is no plateau in the radial profile; plateau=saturated=bad ***make sure that the "DATAPAR" keywords in the phot parameter file have the AIRMASS, FILTER, and EXPTIME are defined: PACKAGE = apphot TASK = datapars (scale = 1.) Image scale in units per pixel (fwhmpsf= 2.5) FWHM of the PSF in scale units (emissio= yes) Features are positive ? (sigma = INDEF) Standard deviation of background in counts (datamin= INDEF) Minimum good data value (datamax= INDEF) Maximum good data value (noise = poisson) Noise model (ccdread= ) CCD readout noise image header keyword (gain = ) CCD gain image header keyword (readnoi= 0.) CCD readout noise in electrons (epadu = 1.) Gain in electrons per count (exposur= EXPTIME) Exposure time image header keyword (airmass= AIRMASS) Airmass image header keyword (filter = FILTER) Filter image header keyword (obstime= ) Time of observation image header keyword (itime = 1.) Exposure time (xairmas= INDEF) Airmass (ifilter= INDEF) Filter (otime = INDEF) Time of observation (mode = ql) ***or whatever the header keyword is in your headers. Run photometry (see "Real Live Photometry" section here) on each star while writing down the order of the stars you photometered in the 'notes.txt' file. Make sure you run photometry on the same number of stars for each pointing. This won't halt this process until running the calibration program, but doing this will make the process much less of a headache. Also, run photometry on only the good images; headache reasoning. After photometry you should have a *.mag.1 file for each image. Now we need a file that lists all of the photometric variables for each star. This file has a format of: night file objectname filter airmass exptime counts mag magerror all of these things are contained in the *.mag.1 files except the name of the stars. The info in the *mag.1 files can be piped into a text file via: ******************************************************************************** terminal> ls a*.mag.1 > mag1.list iraf terminal> txdump @mag1.list image,ifilter,xairmass,itime,flux,mag,merr yes > phot_raw.txt ******************************************************************************** Next you will run an IDL code designed to add the names of the standards stars and output each stars info in the correct format. This program reads in the 'notes.txt' and the 'phot_raw.txt' files. Run the program: IDL> make_calinfo This creates a "night"_full.txt file which contains all of the standard stars that you photometered. The program 'broadcalv2.pro' only handles two filter combinations (color pairs) at a time. So you will have to manually copy and paste the correct filters into the their own text file: "nightFILTERFILTER.txt". 'broadcalv2.pro' needs a specific column format to work, which make_calinfo has done for you. ***It is up to you to take all of the U and B filters (for example) and put them into a file called 'nightUB.txt' and put them in the format: eg. nov16172009 a0010 95_115 U 2.55 15 5988.017 -6.503 0.078 nov16172009 a0010 95_43 U 2.55 15 424116.1 -11.128 0.002 nov16172009 a0012 95_115 B 2.49 10 28987.09 -8.656 0.019 nov16172009 a0012 95_43 B 2.49 10 1532158. -12.963 0.001 nov16172009 a0022 95_115 U 1.22 15 9410.467 -6.994 0.047 nov16172009 a0022 95_43 U 1.22 15 768576.8 -11.774 0.001 nov16172009 a0023 95_115 B 1.22 10 38217.91 -8.956 0.015 nov16172009 a0023 95_43 B 1.22 10 2096252. -13.304 0.001 ***MAKE SURE YOU HAVE THE SAME NUMBER OF STARS PER FILTER PAIR!!! (AKA IMAGES A0010 AND A0012 ARE A PAIR AND NEED THE SAME NUMBER OF STARS IN THE SAME ORDER!!! *Make a file like this one for each color combination. Now you can run broadcalv2.pro. broadcalv2,'monthdaysCOLOR'.txt,/no_extinction The /no_extinction allows the user to enter the coefficients yourself I have been using set airmass coefficients: BOK err WIRO err CTIO err U - 0.50 0.01 0.5 0.01 0.450 0.01 B - 0.25 0.01 0.295 0.004 0.232 0.01 V - 0.15 0.01 0.193 0.004 0.144 0.01 R - 0.10 0.01 0.139 0.004 0.083 0.005 I - 0.07 0.01 0.061 0.011 0.056 0.005 KPNO am coefficients have been extensively studied and can be found at: http://www.noao.edu/kpno/manuals/dim/ in the color correction and extinction section near the bottom. *'broadcalv2.pro' will output 'nightUB.cal' with: night color filter AirmassCoefficient Error Co(Zeropoint) Error C1(color term) Error *Your calibrated magnitude will be found using this equation: M = m(instrumental) + C0 + C1*color + AMcoef*airmass ****Unless you have taken 5 pointings or more of standards in one night you should do your calibrations on a overall run basis. In other words, take the data from all the nights in a run and run the calibration code on the entire run data set. Otherwise you may not have good enough statistics to eliminate bad standard star data points. #########################INCOMPLETE################################################### Next the calibrations need to be put into the header. ***************************************************** ***Make sure the stack.fit files are created!!!!!!!!! ***************************************************** Next you have to put the calibration information into the header of each stack.fit image. You will need the program 'header_cal.pro' found at: /d/users/davec/programs/ *make a text file called 'header_info.txt'. Add the path/stack name, the filter, the colors that you calibrated for this night, and the name of the night in the 'MasterCalibration'file. Example: directory (from stack.list) filter color night ----------------------------------------------------------------- galaxies/ugc8201/bok/U/stack.fit U U-B may2010 galaxies/ugc8201/bok/U/stack.fit U U-V may2010 galaxies/ugc8201/bok/U/stack.fit U U-R may2010 galaxies/ugc8201/bok/U/stack.fit U U-I may2010 ***Each image will need all of the color combinations in the header. run header_cal.pro This creates a text file called 'cal.cl' that can be used to add the calibration info to the appropriate galaxies headers, using IRAF. It is better to pick out each individual galaxy and copy the appropriate lines into IRAF rather than inputing the whole file ex- cl < header_cal.cl Then move and rename the stack.fit to the correct galaxy directory and you are done. update the webpage #########################INCOMPLETE###################################################