Color Image - How to

INSTRUCTIONS FOR MAKING COLOR IMAGE

1. Correct the badpix with a mask. Note that fixpix looks at the stupid header keywords: LTV1 and LTV2. These should be removed from the headers of the images and the masks if you are going to run fixpix.

hedit obj*.imh ltv* del+

Here is the badpix mask for 0.9m (Tek2K_3 ):

2. Get at least 2 images, preferably >3 in BVI. Cut out the area near the galaxy, say the 800 pix near the galaxy:

yalocen r*.fits
filecalc junk.dat "$1-400;$1+399;$2-400;$2+399" form="[%d:%d,%d:%d] "

3. Copy all files to *.fits

cpfits s*.imh del+

4. Run

$SNSEARCH/imregister_new.pl r001.fits r002.fits -out s002.fits -force

to get aligned images.

You may have to set the threshold differently, like thresh=20 or 40

For some reason, one of the images did not work. So I measured a star

imshift obj482.imh r482 xs=-1.38 ys=1.28

5. Bring the skies to zero using "getsky.cl".

This first outputs temp.cl which brings the sky to 0. This also brings the interpolated part of the image to a very negative value. So you also have to run "temp1.cl" to correct for the interpolation.

6. Combine the image

If you have lots of images, just scale on the galaxy.

imdel temp
imcomb c*.fits temp comb=ave reject=avsig scale=mean \\
stat=[385:415,385:415] nhig=1 nlo=1 hth=20000
displ temp 1

or if you have two images, get rid of the cr's. You can check the
noisemodel using stsdas.hst.wfpc program noisem.

imdel test1.imh,test1.pl
imcomb @inb temp comb=av reject=crr gai=2.1 rd=4.5 sn=0.2 pl=temp gro=1
displ temp.imh 1
displ test.pl 2

7. Finally run

t1.cl:
del test.rgb
rgbsun regi regv regb test.rgb \\
rz1=-5. \\
gz1=-5. \\
bz1=-5. \\
rz2=200. \\
gz2=110. \\
bz2=70. log-
!xv test.rgb

Output the file to tif, or whatever. The log plot looked nice, but there was too much noise that appeared as color speckels.

The file then can be edited in PhotoShop to make it look nicer.

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