Innovations of version 3.60 (April 6, 2002)


The dialog box Mosaic from Geometry menu accepts now rotation between the  images in addition to the translation. The pivot of rotation is in the center image 1. 


It is possible to control (on an experimental basis) an Audine camera equipped with a KAF-3200 type CCD.

 

For acquire an image, run the ACQ console command.


 
Command DATA_ANIM

Syntax: DATA_ANIM [IN] [OUT] [X1] [X2] [STEP]

Powerful function allowing for example to interpolate at the same time along wavelength and temporally a whole of spectral data in order to carry out an animation.

The parameter [ IN ] is the name of a text file having the extension LST. It contains two columns. The first give a spectral file name having extension DAT, the second is the date of acquisition of these spectra in Julian day or reduced Julian day. Here contents characteristic of an input file:

290601 245678.345
300701 245689.446
220801 245693.945
.....

It indicates that spectral profile 290601.DAT was acquired the day Julian 245678.345, that spectral profile 300701.DAT was acquired the day Julian 245689.446, that spectral profile 220801.DAT was acquired the day Julian 245693.945, and so on.

The parameter [ OUT] is the name of a text file having the extension LST. It contains two columns. The first give the spectral file name (DAT extension) which will be interpolated, the second is the date of the files interpolated in Julian day or reduced Julian day. Here contents characteristic of a file of an output file:

R1 245679.0
R2 245690.0
R3 245691.0
....

It indicates that command DATA_ANIM must produce spectral profiles in files of names R1.DAT, R2.DAT, R3.DAT, respectively for the dates in Julian days 245679.0, 245690.0, 245691.0.

The parameters [ X1 ] and [ X2 ] define an interval in wavelength for the interpolation which an interpolation step of [STEP].

The mode of interpolation along the temporal axis is linear. One uses an interpolation spline along the wavelengths axis.

Once the interpolated profiles, you can displaying this in a graphic form with the software of your choice then to create animations of the evolution of the spectrum according to time. It is possible also to produce an image of the dynamic spectrum starting from command DATA2IMAGE. Click to see examples here.

Command DATA2IMAGE

Create an image in memory starting from a sequence of text file having extension DAT. The contents of the first file are used to produce the first line of the image. The contents of the second file build the second line of the image, and so on. The text files must contain two columns of real data. The image is built with information of the second column. With final, the size of the image along axis X is equal to the number of lines contained in files DAT and the size along the axis Y is equal to the number of file DAT.

Syntax is:

DATA2IMAGE [INPUT] [COEFFICIENT] [NUMBER]

[ INPUT ] is the generic name of files DAT
[ COEFFICENT ] is a multiplicative parameter by which one multiplies the second column of files DAT before assigning them to the pixels of the image in memory.
[ NUMBER ] is the number of files DAT

The typical application of DATA2IMAGE is the creation of the image of a dynamic spectrum which shows the evolution of the spectral profile according to time. Here a characteristic image:

Each line of this image is an individual spectrum (here the region of the H-alpha line in the spectrum of Omega Orion). The interval of time following the vertical axis is regular. If needed, the spectral profiles are interpolated with command DATA_ANIM.

Command FITS2PIC

Convert a sequence of FITS image into a sequence with the proprietary PIC format. Syntax:

FITS2PIC [IN] [OUT] [NUMBER]

[IN ] is the generic name of the input sequence.
[ OUT ] is the generic name of the output sequence.
[ NUMBER ] is the number of images in the sequence.

Command GEN_OUT

Utility function to generate an output file for command DATA_ANIM, this last allowing to produce dynamic spectra. Syntax:

GEN_OUT [FILE] [TEXT] [X1] [X2] [STEP]

[ NAME ] is the name of output LST file.
[ TEXT ] is the generic name of the first column of LST file.
[ Y1 ] and [ Y2 ] are the date limits of the second column (normally the Julian day).
[ STEP ] is the temporal step of the second column.

For example:

GEN_OUT OUT R 2310 2317 0.5

Generates this file OUT.LST contains:

r01 2310.500000
r02 2311.000000
r03 2311.500000
r04 2312.000000
r05 2312.500000
r06 2313.000000
r07 2313.500000
r08 2314.000000
r09 2314.500000
r10 2315.000000
r11 2315.500000
r12 2316.000000
r13 2316.500000
r14 2317.000000

Command IMAGE2SPEC

Carry out the spectral calibration of an image spectral profile when the position of grating zero order is accessible. Syntax is:

IMAGE2SPEC [FILE] [LINE/MM] [DIST] [P_ZERO] [PIXEL]

[ FILE ]: the name of the file of the calibrated spectral profile which will be created on the disc. It is an ASCII file with two columns. In the first column one finds the wavelength in angströms and in the second the intensity of the spectrum.
[ LINE/MM ]: the number of groove by millimeter of the grating.
[ DIST ]: the distance separating the grating from the CCD in millimeters.
[ P_ZERO ]: the position in pixel of the center of the zero order image along the horizontal axis of the image.
[ PIXEL ]: size of the pixel along the horizontal axis of the image in millimeters.

For an example of application of this command click here.

Command L_BIN

Carry out an operation of binning along vertical axis on a spectrum whose dispersion axis is horizontal. The addition zone along the vertical axis is such as with final the result of the addition contains 93% of the information of the real spectrum. Iris calculates the optimal addition width zone for reduce noise in the result. The max intensity in the binned image is normalized to 32766. The result is an image of the spectral profile where this one is to duplicate 20 times along the vertical axis. Before run the command you must frame the spectrum of a rectangle to be traced with the mouse.

The spectrum before the binning and the zone drawn selection:


Spectral profile after the binning:

 

For an introduction tutorial to spectrography, click here.

Command L_BIN2

Same function that L_BIN, but the normalization   is carried out starting from the most intense pixel which is in the selection zone and not over the entire length of the spectrum.

The spectrum before the binning and the selection zone:

Spectral profile after the binning:

Command L_SKY2

Command allowing to estimate the level of the sky background on both sides of a spectrum. The sky background is modelled by calculating for each columns of the images taken independently the median value of the intensities of the pixels in two zones that one definite interactively. The operator define these two zones by 4 clicks of the mouse as shows it the following image:

The click order of the points is not critical. L_SKY2 then substrat from all the columns the average of the two median intensities calculated in each one of them. The effect is to bring the level of the sky background to zero. It is an essential operation before being able to extract the spectral profile from a spectral image because it fixes the origin of the scale of the intensities.

Command L_SKY3

Command, very similar to L_SKY2, allowing to estimate the level of the sky background on both sides of a spectrum. The sky background is modelled by fitting lines distinct for each columns from the image. The pixels of the image which are used to calculate these fit are in two zones on both sides spectrum that the operator define by 4 clicks of the mouse as shows it the following image:

Command PIC2FITS

Convert a sequence of PIC image into FITS a sequence. Syntax:

PIC2FITS [IN] [OUT] [NUMBER]

[IN ] is the generic name of the input sequence.
[ OUT ] is the generic name of the output sequence.
[ NUMBER ] is the number of images in the sequence.

Command REMOVE@

Delete all the files of the working directory starting with the character @. Equivalent with command DOS: DEL @ *. *

Command TEXT

Allows to write a text in the image. This function modifies the intensity of the pixels in the 16-bits image. You can retrogress while using the button " undo " tools bar.

Syntax is:

TEXT [TEXT] [X] [Y] [INTENSITY]

[ TEXT ] is the contents of the text.
[ X ] and [ Y ] are the coordinates in pixels of the position of the beginning of the text.
[ INTENSITY ] is the intensity of the text, a number ranging between 0 and 32767.

Example:

Text Zeta_Tau_____April_2002 30 5 32000

Note the use of the character " _ " to write white.