Global Options

GCX has a large number of configuration options. They can be accesses through the options dialog, which can be brought up by pressing O or File/Edit Options. Clicking on ``save'' in the options dialog will update the default configuration file (.gcxrc), located in the home directory.

When the program stars, it looks for the configuration file. If it cannot be read, it will initialise all parameters with defaults.

There are two ways of modifying some of the options for a specific run: either use the -S command-line option for each option that needs to change, or make a configuration file that contains the option changes for the run and use the -r command-line option. The name used in the configuration file is listed with each option.

File and Device Options

CFA to use with raw FITS files

Config file	.file.default_cfa
Type	multiple choice
Choices	none RGGB BGGR GRBG GBRG
Default	none

Serial line for gps receiver control

Config file	.file.gps_serial
Type	string
Default	/dev/ttyS0

Command for uncompressing files

The command used to uncompress files; it should take the filename as an argument, and output the uncompressed stream on stdout. The command is called when trying to open files with the name ending in .gz, .zip or .z

Config file	.file.uncompress
Type	string
Default	zcat

Command for compressing files

The command used to uncompress files; it should take the filename as an argument, and replace the file with the compressed version.

Config file	.file.compress
Type	string
Default	gzip -f

Gnuplot command

Command used to invoke gnuplot for plotting graphs in a window.

Config file	.file.gnuplot
Type	string
Default	gnuplot -persist

Plot to file

Create a gnuplot file instead of calling gnuplot directly.

Config file	.file.plot_to_file
Type	boolean
Default	no

Monospaced Font

The monospaced font used to display FITS headers and help pages.

Config file	.file.mono_font
Type	string
Default	-misc-fixed-medium-r-*-*-*-120-*-*-*-*-*-*

Phot report file

Output file for obscript phot commands.

Config file	.file.phot_out_fn
Type	string
Default	phot.out

Obs files search path

Path (colon-delimited list of directories) searched when opening observation script files.

Config file	.file.obs_path
Type	string
Default	.:../obs

Rcp files search path

Path (colon-delimited list of directories) searched when opening recipe files.

Config file	.file.rcp_path
Type	string
Default	.:../rcp

GSC location

Location of gsc catalog files. Full pathname of the toplevel gsc directory.Make sure all subdirs and files names use lower case.

Config file	.file.gsc_path
Type	string
Default	/usr/share/gcx/catalogs/gsc

Tycho2 location

Full pathname of the tycho2 catalog file.

Config file	.file.tycho2_path
Type	string
Default	/usr/share/gcx/catalogs/tycho2

Catalog files

Colon-delimited list of catalog files to be searched or loaded into the in-memory catalog. The elements of the list are glob- and tilde-expanded so for instance /*.gcx will load all .gcx files from the home directory. The files are expected to be in gcx recipe format.

Config file	.file.catalog_path
Type	string
Default	/usr/share/gcx/catalogs/*.gcx

Preload catalogs

Enable preloading the native format catalog files into memory for faster searching. Preloading takes significantly more time that searching the on-disk files by name; it's recommended only for merging catalogs or similar operations.

Config file	.file.catalog_preload
Type	boolean
Default	no

Edb directory

Directory containing edb object files.

Config file	.file.edb_dir
Type	string
Default	/usr/share/gcx/catalogs/edb

Aavso validation file

Location of aavso validation file. The validation file is used to determine the designation given a star name. Any of the validation file formats can be used, except the 'short form by name'. The designation should start in column 0 and the name in column 10.

Config file	.file.validation
Type	string
Default	valnam.txt

Force unsigned FITS

Force all values read from a fits file to be interpreted as unsigned numbers (supporting broken files generated that way).

Config file	.file.unsigned_fits
Type	boolean
Default	no

Western longitudes

Interpret fits header longitudes as western, rather than eastern. Report file longitudes are always western.

Config file	.file.west_long
Type	boolean
Default	yes

Report converter output format

The output format string used by the report converter. See the on-line help for a description.

Config file	.file.tab_format
Type	string
Default	name ra dec mjd smag "v" flags

Auto-unload frames

Unload unmodified frames from the frame list whenever possible to reduce memory usage. The frames will have to be reloaded if needed again.

Config file	.file.mem_save
Type	boolean
Default	yes

New frame width

The width of a newly-created blank frame in pixels.

Config file	.file.new_width
Type	integer
Default	1024

New frame height

The height of a newly-created blank frame in pixels.

Config file	.file.new_height
Type	integer
Default	768

New frame scale

The default wcs scale of a newly-created blank frame in arc seconds per pixel.

Config file	.file.new_scale
Type	real
Default	4.00

Merge positional tolerance

The distance in arc seconds below which we consider two stars to be the same object when merging recipe files.

Config file	.file.merge_tolerance
Type	real
Default	3.000

Fits Field Names

Fits field for X coordinate of reference pixel

Config file	.file.fits.crpix1
Type	string
Default	CRPIX1

Fits field for Y coordinate of reference pixel

Config file	.file.fits.crpix2
Type	string
Default	CRPIX2

Fits field for WCS R.A. of reference pixel

Config file	.file.fits.crval1
Type	string
Default	CRVAL1

Fits field for WCS Dec of reference pixel

Config file	.file.fits.crval2
Type	string
Default	CRVAL2

Fits field for degrees/pixel in R.A.

Config file	.file.fits.cdelt1
Type	string
Default	CDELT1

Fits field for degrees/pixel in dec

Config file	.file.fits.cdelt2
Type	string
Default	CDELT2

Fits field for field rotation

Config file	.file.fits.crota1
Type	string
Default	CROTA1

Fits field for equinox of WCS

Config file	.file.fits.equinox
Type	string
Default	EQUINOX

Fits field for equinox of WCS

Config file	.file.fits.epoch
Type	string
Default	EPOCH

Fits field for object name

Config file	.file.fits.object
Type	string
Default	OBJECT

Fits field for object R.A.

Config file	.file.fits.objctra
Type	string
Default	OBJCTRA

Fits field for object dec

Config file	.file.fits.objctdec
Type	string
Default	OBJCTDEC

Fits field for image scale

Config file	.file.fits.secpix
Type	string
Default	SECPIX

Fits field for field center

Config file	.file.fits.ra
Type	string
Default	RA

Fits field for field center

Config file	.file.fits.dec
Type	string
Default	DEC

Fits field for filter name

Config file	.file.fits.filter
Type	string
Default	FILTER

Fits field for exposure time

Config file	.file.fits.exptime
Type	string
Default	EXPTIME

Fits field for julian date of observation

Config file	.file.fits.jdate
Type	string
Default	JDATE

Fits field for modified julian date of observation

Config file	.file.fits.mjd
Type	string
Default	MJD

Fits field for date/time of observation

Config file	.file.fits.dateobs
Type	string
Default	DATE-OBS

Fits field for time of observation

Config file	.file.fits.timeobs
Type	string
Default	TIME-OBS

Fits field for telescope name

Config file	.file.fits.telescop
Type	string
Default	TELESCOP

Fits field for focus designation

Config file	.file.fits.focus
Type	string
Default	FOCUS

Fits field for telescope aperture

Config file	.file.fits.aperture
Type	string
Default	APERT

Fits field for focal length

Config file	.file.fits.flen
Type	string
Default	FLEN

Fits field for instrument name

Config file	.file.fits.instrument
Type	string
Default	INSTRUME

Fits field for observer name

Config file	.file.fits.observer
Type	string
Default	OBSERVER

Fits field for latitude of observing site

Config file	.file.fits.latitude
Type	string
Default	LAT-OBS

Fits field for longitude of observing site

Config file	.file.fits.longitude
Type	string
Default	LONG-OBS

Fits field for altitude of observing site

Config file	.file.fits.altitude
Type	string
Default	ALT-OBS

Fits field for airmas

Config file	.file.fits.airmass
Type	string
Default	AIRMASS

Fits field for sensor temperature

Config file	.file.fits.snstemp
Type	string
Default	SNS_TEMP

Fits field for horisontal binning

Config file	.file.fits.binx
Type	string
Default	CCDBIN1

Fits field for vertical binning

Config file	.file.fits.biny
Type	string
Default	CCDBIN2

Fits field for horisontal window origin

Config file	.file.fits.skipx
Type	string
Default	CCDSKIP1

Fits field for vertical window origin

Config file	.file.fits.skipy
Type	string
Default	CCDSKIP2

Fits field for electrons per ADU

Config file	.file.fits.eladu
Type	string
Default	ELADU

Fits field for average bias of frame

Config file	.file.fits.dcbias
Type	string
Default	DCBIAS

Fits field for readout noise

Config file	.file.fits.rdnoise
Type	string
Default	RDNOISE

Fits field for multiplicative noise coefficient

Config file	.file.fits.flnoise
Type	string
Default	FLNOISE

Fits field for color-field-array layout

Config file	.file.fits.cfa_fmt
Type	string
Default	CFA_FMT

Fits field for white balance calibration

Config file	.file.fits.whitebal
Type	string
Default	WHITEBAL

General Observation Setup Data

Latitude of observing site

Used to annotate frames' fits header, and for calculation of objects' hour angle and airmass. Set in decimal degress.

Config file	.obs.latitude
Type	real
Default	44.431

Longitude of observing site

Used to annotate frames' fits header, and for calculation of objects' hour angle and airmass. Set in decimal degress, E longitudes negative.

Config file	.obs.longitude
Type	real
Default	-26.114

Altitude of observing site

Used to annotate frames' fits header, and for scintillation calculations; In meters above sea level.

Config file	.obs.altitude
Type	real
Default	75.0

Observer name

Used to annotate frames' fits header.

Config file	.obs.observer
Type	string
Default	R. Corlan

Observer code

Used to annotate AAVSO format reports.

Config file	.obs.obscode
Type	string
Default	CXR

Telescope name

Used to annotate frames' fits header.

Config file	.obs.telescope
Type	string
Default	SCT

Telescope focal length

Used to annotate frames' fits header, and for calculating the initial WCS image scale (together with the camera pixel size). In centimeters.

Config file	.obs.flen
Type	real
Default	200.0

Flipped field

Set the inital wcs as flipped (CDELT1 and CDELT2 having opposite signs). The star matching algorithm does not handle flips, so this has to be set right. A normal (non-flipped) field has N up and W to the right.

Config file	.obs.flipped
Type	boolean
Default	no

Telescope aperture

Used to annotate frames' fits header, and for estimating scintillation noise. In centimeters.

Config file	.obs.aperture
Type	real
Default	30.0

Focus designation

Used to annotate frames' fits header.

Config file	.obs.focus
Type	string
Default	Cassergrain

List of filters

Space-delimited list of filters used to set the choices in the obscript dialog. They are also used as default names for the filters in filter wheels that don't supply their own names

Config file	.obs.filters
Type	string
Default	v r b i RI GI BI clear

INDI connection options

INDI server host

Config file	.indi.indi_host_name
Type	string
Default	localhost

INDI server port

Config file	.indi.indi_host_port
Type	integer
Default	7624

INDI name of main camera

Config file	.indi.camera_main_indi_name
Type	string
Default	CCD Simulator

INDI port for main camera control

Config file	.indi.camera_main_indi_port
Type	string
Default	/dev/video0

INDI name of guide camera

Config file	.indi.camera_guide_indi_name
Type	string
Default	CCD Simulator

INDI port for guide camera control

Config file	.indi.camera_guide_indi_port
Type	string
Default	/dev/video0

INDI name of Telescope

Config file	.indi.scope_indi_name
Type	string
Default	Telescope Simulator

INDI port for telescope control

Config file	.indi.scope_indi_port
Type	string
Default	/dev/ttyS0

INDI name of Telescope

Config file	.indi.fwheel_indi_name
Type	string
Default	Telescope Simulator

INDI port for telescope control

Config file	.indi.fwheel_indi_port
Type	string
Default	/dev/ttyS0

Telescope control options

Eastern limit for goto ops (hour angle)

Config file	.tel.elimit
Type	real
Default	-1.0

Enable eastern limit

Config file	.tel.elimit_en
Type	boolean
Default	no

Western limit for goto ops (hour angle)

Config file	.tel.wlimit
Type	real
Default	1.0

Enable western limit

Config file	.tel.wlimit_en
Type	boolean
Default	no

Southern limit for goto ops (degrees)

Config file	.tel.slimit
Type	real
Default	-45.0

Enable southern limit

Config file	.tel.slimit_en
Type	boolean
Default	yes

Northern limit for goto ops (degrees)

Config file	.tel.nlimit
Type	real
Default	80.0

Enable northern limit

Config file	.tel.nlimit_en
Type	boolean
Default	yes

Abort obscript gotos that cause a meridian flip

Config file	.tel.abort_flip
Type	boolean
Default	yes

Mount speed when centering (times sidereal rate)

Config file	.tel.centering_speed
Type	real
Default	32.0

Mount speed when guiding (times sidereal rate)

Config file	.tel.centering_speed
Type	real
Default	0.5

Use timed centering moves for small slews

Config file	.tel.use_centering
Type	boolean
Default	yes

Precess coordinated sent to the scope to the epoch of the day

Config file	.tel.precess_eod
Type	boolean
Default	yes

Amount of gear play we take out at the end of slews (degrees)

Config file	.tel.gear_play
Type	real
Default	0.10

Mount stabilisation delay (ms)

Config file	.tel.stabilisation_delay
Type	integer
Default	1000

Amount of pointing dither between frames (arcmin)

Config file	.tel.dither
Type	real
Default	0.5

Enable pointing dithering

Config file	.tel.dither_en
Type	boolean
Default	no

Max error we accept in telescope pointing (degrees)

Config file	.tel.max_point_err
Type	real
Default	0.05

Guiding options

Guiding algorithm

Algorithm used to determine the guide star position error. The reticle algorithm determines the error as the ratio between the total flux in box-shaped areas located horisontally and vertically around the target position; The ratioed reticle tries to maintain the initial flux ratio, rather than a unit ratio.

Config file	.guide.algorithm
Type	multiple choice
Choices	centroid reticle ratioed_reticle
Default	centroid

Reticle size

Size of the reticle in pixels. Must be an even value.

Config file	.guide.reticle_size
Type	integer
Default	2

Centroid area radius

Radius of area inside which the target centroid is calculated.

Config file	.guide.centroid_box
Type	integer
Default	2

Guide box size

Size of box around the target guide star position used by the guiding algorithm.

Config file	.guide.box_size
Type	integer
Default	16

Guide box zoom

Zoom level of the small image of the guide box.

Config file	.guide.zoom
Type	integer
Default	4

CCD Reduction options

Method used for demosaic

Config file	.ccdred.demosaic_method
Type	multiple choice
Choices	bilinear vng
Default	bilinear

Method used for white-balance correction

Config file	.ccdred.whitebal_method
Type	multiple choice
Choices	none camera user
Default	none

Minimum backgound sigmas

Minimum number of sigmas the background must have for multiplicative background alignment to be performed when stacking frames.

Config file	.ccdred.min_bg_sigmas
Type	real
Default	3.0

Method used for stacking frames

Config file	.ccdred.stack_method
Type	multiple choice
Choices	average median kappa_sigma mean_median
Default	kappa_sigma

Iteration limit for stacking operations

Config file	.ccdred.iterations
Type	integer
Default	4

Clipping sigmas for mmedian and k-s

Config file	.ccdred.sigmas
Type	real
Default	2.0

Run CCD reductions automatically on frame display

Config file	.ccdred.auto
Type	boolean
Default	yes

Bad pixel sigmas

Number of frame sigmas a pixel must deviate from the median of its neighbours to be considered defect.

Config file	.ccdred.badpix_sigmas
Type	real
Default	12.000

Star Detection and Search Options

Star Detection SNR

A star must be above this threshold above the backround to be considered for detection. Expressed in sigmas of the image. Useful range between 3 and 24.

Config file	.stars.det_snr
Type	real
Default	9.0

Maximum Detected Stars

The maximum number of starts the program will extract from an image. If more are found, only the brightest are kept.

Config file	.stars.det_maxstars
Type	integer
Default	200

Maximum Catalog Stars

The maximum number of starts the program will extract from a field star catalog. If more are found, only the brightest are kept.

Config file	.stars.cat_maxstars
Type	integer
Default	300

Faintest Magnitude for Catalog Stars

Config file	.stars.cat_maxmag
Type	real
Default	16.0

Maximum Radius for Catalog Stars

The maximum radius from the frame center in which we look for catalog stars. The actual radius depends on the frame size; this is a global limit. In minutes of arc.

Config file	.stars.cat_maxradius
Type	real
Default	120.0

Wcs Fitting Options

Scale tolerance

The maximum amount by which the image scale is changed during the fit. A value of 0.1 implies that scales between 0.9 and 1.1 are accepted. Using a lower value for this parameter will decrease the running time and reduce the chances for an incorrect fit.

Config file	.wcs.fit_scale
Type	real
Default	0.10

Star position tolerance

The maxiumum position error, in pixels, between a star and a catalog position at which we still consider that the two match. It is unadvisable to increase this parameter much without a coresponding increase in the minimum number of pairs, or the chances for incorrect fits are greatly augumented.

Config file	.wcs.fit_tol
Type	real
Default	1.5

Rotation tolerance

Maximum accepted field rotation, in degress A value of 180 will match fields with any rotation. Using a lower value for this parameter will decrease the running time and reduce the chances for an incorrect fit.

Config file	.wcs.fit_rot
Type	real
Default	180.0

Minimum number of pairs

When the algorithm finds a solution with at least this many pairs, it considers it has found a good match and stops. Using less than 5 pairs will likely give many incorrect fits in crowded fields

Config file	.wcs.fit_min_pairs
Type	integer
Default	5

Max skip

The maximum number of stars that don't seem to have a match in the catalog and are skipped during the search

Config file	.wcs.max_skip
Type	integer
Default	20

Maximum pairs

Maximum number of pairs fitted. After finding this many, the algorithm stops.

Config file	.wcs.max_pairs
Type	integer
Default	50

Min A-B distance

The minimum distance between two stars to be used as an initial wcs hypothesis.

Config file	.wcs.min_ab_dist
Type	real
Default	100.000

Max error for WCS validation

Maximum RMS position error of all pairs at which the WCS is validated. Expressed in pixels.

Config file	.wcs.validate_err
Type	real
Default	1.50

Min pairs for WCS validation

The minimum number of pairs needed to validate a WCS solution.

Config file	.wcs.validate_pairs
Type	integer
Default	3

Scale change per iteration

Maximum scale change accepted when iterating the WCS solution. This is an internal parameter few people (if any) will want to change.

Config file	.wcs.max_s_chg
Type	real
Default	0.0200

Default image scale

Default image scale used for setting the initial WCS when this information is not available from the frame header. In arc seconds per pixel

Config file	.wcs.default_scale
Type	real
Default	1.50

Plate Model

Model used for plate to projection plane transformations. Simple consists of translation, scale and rotation; Linear is a general affine transformation, which includes shear; Auto selects a plate model based on the number of star pairs.

Config file	.wcs.plate_model
Type	multiple choice
Choices	auto simple linear
Default	auto

Calculate Refraction

Enable the calculation of refracted positions of stars. If the time and/or geographical coordinates aren't precise, this option is better turned off.

Config file	.wcs.refraction
Type	boolean
Default	no

Aperture Photometry Options

Radius of central aperture

Radius, in pixels, of the central aperture from which the star flux is measured.

Config file	.aphot.r1
Type	real
Default	4.0

Inner radius of sky annulus

Inner radius, in pixels, of the annulus surrounding the star from which the sky flux is estimated.

Config file	.aphot.r2
Type	real
Default	9.0

Outer radius of sky annulus

Outer radius, in pixels, of the annulus surrounding the star from which the sky flux is estimated.

Config file	.aphot.r3
Type	real
Default	18.0

Center apertures

Try to center the measuring aperture on the star before performing the measurement.

Config file	.aphot.auto_center
Type	boolean
Default	yes

Max centering error

The maximum amount a measuring aperture is moved when auto-centering (in pixels).

Config file	.aphot.center_err
Type	real
Default	1.00

Discard unlocated standards

When this option is set, standard stars than cannot be located within the specified error radius when centering apertures are not used in the solution.

Config file	.aphot.discard_unlocated
Type	boolean
Default	yes

Move targets

Update the world coordinates of stars that don't have the Astrometric flag set when their apertures are centered. Useful for moving targets like asteroids or comets or instances where the coordinates of the target are only approximately known.

Config file	.aphot.move_targets
Type	boolean
Default	no

Max center distance

The maximum distance from the frame center at which a standard star must lie in order to be used in the photometry solution. The distance is expressed relative to half the frame's diagonal. A value of 1 will include all stars. This option is useful when we expect large flat-fielding errors or distorted star images at the frame's corners.

Config file	.aphot.std_max_distance
Type	real
Default	1.00

Sky method

Method used for sky estimation: Average uses the average of the sky annulus pixels; it's not recommended, as it will not reject nearby stars. Median uses the median of the sky pixels; it's fast and robust, but will not average out quantisation noise. Kappa-Sigma computes the sky value by clipping off pixels too far away from the median, and averaging the rest; the standard deviation of the remaining pixels is calculated, and the clipping/averaging is iterated until values converge; Synthetic mode is calaulated as 3*median - 2*mean, where median and mean are the statistics of the clipped sky annulus.

Config file	.aphot.sky_method
Type	multiple choice
Choices	average median kappa_sigma synthetic_mode
Default	kappa_sigma

Region growing

Amount, in pixels, by which regions containing peaks are grown in order to exclude the tails of spurious stars in the sky aperture. A value larger than 3 is silently clamped at 3. Region growing only applies to the kappa-sigma and synthetic mode sky methods.

Config file	.aphot.grow
Type	integer
Default	2

Sigmas

Rejection limit of the mean-median, kappa-sigma and synthetic mode sky estimation methods, in sigmas.

Config file	.aphot.sigmas
Type	real
Default	3.0

Saturation limit

The value over which we mark the stars as being "bright", i.e. possibly saturated.

Config file	.aphot.sat_limit
Type	real
Default	48000.000

Instrumental band

Name of band the stars are measured into. Used when the frame being reduced does not specify a filter or the Force iband option is set.

Config file	.aphot.iband
Type	string
Default	v

Force iband

Override the filter specification from the frame header with the one set in the Instrumental band parameter.

Config file	.aphot.force_iband
Type	boolean
Default	no

Default catalog error

Default standard magnitude error used when a value is not available.

Config file	.aphot.def_std_err
Type	real
Default	0.050

Alpha

Parameter of the robust fitting alogorithm. It sets the fwhm of the rejection function (in standard deviations).

Config file	.aphot.alpha
Type	real
Default	2.000

Beta

Parameter of the robust fitting alogorithm. It sets the sharpness of the rejection function, with higher values resulting in a sharper falloff.

Config file	.aphot.beta
Type	real
Default	2.000

Multi-Frame Photometry Options

Bands setup

A string which specifies the color indices against which we reduce various bands. It consists of a space-separated list of specifiers of the form: band(b1-b2)[=k/kerr]. In this case, "band" will be reduced against the b1-b2 color index. The optional k and kerr set the default transformation coefficient and it's error for the specified band, like for example v(b-v)=0.06/0.002.

Config file	.mframe.bands
Type	string
Default	b(b-v) v(b-v) r(v-r) i(v-i)

Outlier threshold

Threshold in standard error over which we flag stars as "outliers" for easy identification. Outliers are not excluded from the fit; they are down-weighted by a factor depending on the values of the alpha and beta robust fit parameters.

Config file	.mframe.outlier
Type	real
Default	3.000

Zeropoint outlier threshold

Threshold in standard error over which an image frame is marked as an outlier of the extinction fit. The existance of an outlier frame usually shows that transparency has had a significant change around that time. As a result, calculation of all-sky zeropoints is inhibited in the vicinity of an outlier frame, until a well-fitting frame is encountered.

Config file	.mframe.zp_outlier
Type	real
Default	2.000

Minimum airmass variance

The minimum variance of a data set's airmass for which we try to fit an extinction coefficient. For datasets with lower variance, the extinction coefficient is not considered - which doesn't affect the result, as all frames are taken at nearly the same airmass.

Config file	.mframe.min_am_variance
Type	real
Default	0.0010

Minimum color variance

The minimum variance of a data set's color index for which we try to fit a transformation coefficient. For datasets with lower variance, the transformation coefficient is not fitted, as the possibility of obtaining a meaningless value is quite real.

Config file	.mframe.min_color_variance
Type	real
Default	0.1000

Airmass range

Relative size of the range of airmasses over which we calculate frame zeropoints when doing all-sky reduction. It is expressed relative to the airmass range of the valid standard frames. For example, if the standard frames are taken at airmasses between 1.5 and 2.0, an airmass range of 2.0 will enable all-sky zeropoint calculations for frames with airmasses between 1.25 and 2.25.

Config file	.mframe.airmass_range
Type	real
Default	2.000

Airmass maximum range

The absolute maximum amount we add to or subtract from the standard frames' airmass range when calculating the range in which frames which are reduced all-sky must lie.

Config file	.mframe.airmass_max_range
Type	real
Default	0.500

Limiting magnitude from zeropoint

The amount we subtract from the zeropoint of a frame in order to obtain the limiting magnitude used for reporting purposes.

Config file	.mframe.lmag_from_zp
Type	real
Default	7.000

Star Display Options

Label Target Stars

Show name labels for target stars

Config file	.display.target_labels
Type	boolean
Default	yes

Label Catalog Objects

Show name labels for catalog objects

Config file	.display.cat_labels
Type	boolean
Default	no

Label Standard Stars

Show magitude labels (with the decimal point omitted) for standard stars

Config file	.display.std_labels
Type	boolean
Default	yes

Standard Star Label Band

The band from which the magnitude used for standard star labeling is taken

Config file	.display.std_label_band
Type	string
Default	v

Minimum star size

The minimum radius of a star symbol on screen, in pixels

Config file	.display.min_sz
Type	integer
Default	1

Maximum display star size

The maximum radius of a star symbol on screen, in pixels.

Config file	.display.max_sz
Type	integer
Default	18

Default display star size

The default radius of a star symbol on screen, used when no magnitude information is known; in pixels.

Config file	.display.default_sz
Type	integer
Default	6

Display pixels per magnitude

The amount the star symbols increase in radius for an increase in brightness of 1 magnitude; in pixels

Config file	.display.pix_per_mag
Type	real
Default	1.00

Brightest symbol magnitude

The magnitude at which we stop increasing star symbol sizes

Config file	.display.maxmag
Type	real
Default	5.0

Display limiting magnitude

Magnitude of the faintest displayed objects

Config file	.display.dlimmag
Type	real
Default	17.0

Show fainter stars

Show stars fainter than the display limiting magnitude (at minimum size)

Config file	.display.dlimfainter
Type	boolean
Default	no

Zoom star shapes

Scale star shapes when the image is zoomed. Regardless of the value of this parameter, aphot shapes are always zoomed, while blob symbols never are.

Config file	.display.zoom
Type	boolean
Default	yes

Star shapes zoom limit

The maximum scale factor applied to star shapes. This limit does not apply to aphot shapes.

Config file	.display.zoom_limit
Type	integer
Default	4

Plot position errors

Draw the amount the apertures were moved from their catalog position when stars are centered.

Config file	.display.plot_err
Type	boolean
Default	yes

Plot error scale

The amount by which the position errors are multiplied when the position error plot is generated.

Config file	.display.plot_err_scale
Type	real
Default	100.0

Star Display Colors

Autodected Stars Color

Config file	.display.color.simple
Type	multiple choice
Choices	red orange yellow green cyan blue light_blue gray white
Default	green

Field Stars Color

Config file	.display.color.field
Type	multiple choice
Choices	red orange yellow green cyan blue light_blue gray white
Default	red

Standard Stars Color

Config file	.display.color.apstd
Type	multiple choice
Choices	red orange yellow green cyan blue light_blue gray white
Default	red

Target Stars Color

Config file	.display.color.target
Type	multiple choice
Choices	red orange yellow green cyan blue light_blue gray white
Default	red

Catalog Objects Color

Config file	.display.color.catalog
Type	multiple choice
Choices	red orange yellow green cyan blue light_blue gray white
Default	yellow

User-Marked Stars Color

Config file	.display.color.usel
Type	multiple choice
Choices	red orange yellow green cyan blue light_blue gray white
Default	green

Align Stars Color

Config file	.display.color.align
Type	multiple choice
Choices	red orange yellow green cyan blue light_blue gray white
Default	orange

Selected Stars Color

Config file	.display.color.selected
Type	multiple choice
Choices	red orange yellow green cyan blue light_blue gray white
Default	white

Star Display Shapes

Autodected Stars Shape

Config file	.display.shape.simple
Type	multiple choice
Choices	circle square blob aphot diamond cross
Default	square

Field Stars Shape

Config file	.display.shape.field
Type	multiple choice
Choices	circle square blob aphot diamond cross
Default	diamond

Standard Stars Shape

Config file	.display.shape.apstd
Type	multiple choice
Choices	circle square blob aphot diamond cross
Default	aphot

Target Stars Shape

Config file	.display.shape.target
Type	multiple choice
Choices	circle square blob aphot diamond cross
Default	cross

Catalog Objects Shape

Config file	.display.shape.catalog
Type	multiple choice
Choices	circle square blob aphot diamond cross
Default	diamond

User-Marked Stars Shape

Config file	.display.shape.usel
Type	multiple choice
Choices	circle square blob aphot diamond cross
Default	circle

Align Stars Shape

Config file	.display.shape.align
Type	multiple choice
Choices	circle square blob aphot diamond cross
Default	circle

Synthetic Star Generation Options

Type of star profile

Profile function used to generate synthetic stars.

Config file	.synth.profile
Type	multiple choice
Choices	gaussian moffat
Default	gaussian

FWHM

The FWHM of synthetically-generated stars in pixels.

Config file	.synth.fwhm
Type	real
Default	2.50

Moffat beta

The beta parameter of the Moffat function.

Config file	.synth.beta
Type	real
Default	4.00

Zero Point

Zero point (magnitude of a star with a total flux of 1) used to scale synthetic stars.

Config file	.synth.zp
Type	real
Default	23.00

Oversampling

Oversampling factor when generating the reference psf.

Config file	.synth.oversample
Type	integer
Default	11

On-line Catalogs

Vizquery command

Config file	.query.vizquery
Type	string
Default	vizquery

Maximum Catalog Stars

The maximum number of starts the program will download from a field star catalog.

Config file	.query.maxstars
Type	integer
Default	5000

Maximum Radius for Catalog Stars

The maximum radius from the frame center in which we look for catalog stars. The actual radius depends on the frame size; this is a global limit. In minutes of arc.

Config file	.query.maxradius
Type	real
Default	20.0