A Space & astronomy forum. SpaceBanter.com

Go Back   Home » SpaceBanter.com forum » Astronomy and Astrophysics » Amateur Astronomy
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Background subtraction kit



 
 
Thread Tools Display Modes
  #1  
Old January 28th 05, 04:35 PM
HAVRILIAK
external usenet poster
 
Posts: n/a
Default Background subtraction kit

Olympus provides a free "Background Subtraction Kit" as an alternative to
flatfield exposures for CCD imaging. I download the kit into a know folder
and then click on the background.exe file and it rapidly installs the
routine. What shows up is a file with the same name. I double (or single)
click on the file and ir reinstalls itself. The Figure of their application
never shows up. Anyone familiar with this routine, your help will be greately
appreciated.
  #2  
Old January 28th 05, 05:49 PM
Cougar
external usenet poster
 
Posts: n/a
Default

HAVRILIAK wrote:

Olympus provides a free "Background Subtraction Kit" as an alternative to
flatfield exposures for CCD imaging. I download the kit into a know folder
and then click on the background.exe file and it rapidly installs the
routine. What shows up is a file with the same name. I double (or single)
click on the file and ir reinstalls itself. The Figure of their application
never shows up. Anyone familiar with this routine, your help will be greately
appreciated.


Sounds like one of those old fashioned manually operated viruses. :-b

~ Cougar
  #3  
Old January 28th 05, 07:17 PM
Ralph Hertle
external usenet poster
 
Posts: n/a
Default

HAVRILIAK wrote:
Olympus provides a free "Background Subtraction Kit" as an alternative to
flatfield exposures for CCD imaging. I download the kit into a know folder
and then click on the background.exe file and it rapidly installs the
routine. What shows up is a file with the same name. I double (or single)
click on the file and ir reinstalls itself. The Figure of their application
never shows up. Anyone familiar with this routine, your help will be greately
appreciated.



HAVRILIAK:

Photoshop can remove background data. One way is that one may identify one
of the background pixel colors and remove every instance of that color in
the file. Do that for all selected background colors by picking color pixel
by color pixel. Those colors are also deleted everywhere including from the
desired image data.

Stacking different images so processed should cancel out the deletions fro,
the intended image areas, and the backgoround would be clear.

Obviously, one may want to see the subtle gradations.......

Ralph Hertle

  #4  
Old January 28th 05, 09:00 PM
canopus56
external usenet poster
 
Posts: n/a
Default

No-archive: yes
HAVRILIAK wrote:
Olympus provides a free "Background Subtraction Kit" as an

alternative to
flatfield exposures for CCD imaging.

How about a link, so others can look at it? - Canopus56

  #5  
Old January 29th 05, 01:25 AM
Chris L Peterson
external usenet poster
 
Posts: n/a
Default

On 28 Jan 2005 15:35:41 GMT, (HAVRILIAK) wrote:

Olympus provides a free "Background Subtraction Kit" as an alternative to
flatfield exposures for CCD imaging. I download the kit into a know folder
and then click on the background.exe file and it rapidly installs the
routine. What shows up is a file with the same name. I double (or single)
click on the file and ir reinstalls itself. The Figure of their application
never shows up. Anyone familiar with this routine, your help will be greately
appreciated.


What you download should be an EXE that starts the installer, using the
Windows Installer application. you should probably do this from your
desktop, or a temp folder. When you install, there is an option to set
the install path. You probably just want the default (C:\Program
Files\Olympus\Background Subtraction Toolkit). If you don't tell the
installer to create an icon on your desktop and start menu, you will
have to go to the install folder manually to run the program.

Keep in mind this is a Java app. As such, you need to install a Java
runtime engine on your computer before you can use the program. The
actual executable is called backgroundsubtractiontoolkit.jar.

I tested the installation process and had no problem. I didn't test the
app itself because I don't have Java on my machine, and am not willing
to install it. But if you don't mind Java, it looks like this app should
work fine.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com
  #6  
Old January 29th 05, 01:48 AM
Ralph Hertle
external usenet poster
 
Posts: n/a
Default

HAVRILIAK wrote:
Olympus provides a free "Background Subtraction Kit" as an alternative
to flatfield exposures for CCD imaging. I download the kit into a know
folder and then click on the background.exe file and it rapidly
installs the routine. What shows up is a file with the same name. I
double (or single) click on the file and ir reinstalls itself. The
Figure of their application never shows up. Anyone familiar with this
routine, your help will be greately appreciated.



HAVRILIAK:

Photoshop can remove background data. One way is that one may identify one
of the background pixel colors, e.g., a deep black. and remove every
instance of that color in the file. A different color may be substituted
for the selected color. Do that for all selected background colors by
picking color pixel by color pixel. Those colors are also deleted or
substituted everywhere in the file including from the desired image data.

Stacking different images so processed should cancel out the deletions from
the intended image areas, and the background would be modified or appear clear.

Obviously, one may want to see the subtle gradations.......

.....................


I resubmitted this message to fix some typos. One more idea occurs.

I want to add that there is a computer technique that enhances the
sharpness of the figure in a relationship to the background image.

For example, I use MicroStation CAD in my work in architecture and product
designing. Instead of a black background color for the computer monitor
screen against which all line work is placed, I set the background color to
be a dark eye-ease school blackboard green, dark gray, or dark gray-blue.
These low saturation (muted) darker colors are about 25% on a scale of
0-255. 0 being black and 255 being the maximum intensity of the hue in an
RGB scale, for example.

A high resolution 24 or 32-bit color monitor and full color graphics (video
adapter) board is needed. This technique will not work with a monitor that
doesn't display 16.4 M colors (or 255^3) where each of the three RGB colors
has 255 degrees of intensity. That type of monitor and display board
produces the number of possible color gradations of 255^3 at each pixel.
That's the number of combinatorial possibilities of color at each displayed
pixel (255 x 255 x 255). That produces fine blends of color and subtle
color hue and intensity gradations.

My Monitors are IBM 21" P-260 CRTs that each have 1200 x 1600 displayed
pixels at full 32-bit color. The graphics board is an ATI FireGL3 8800 that
displays a hi-res HST image of a star field across the two monitors. That
image, however divided, is 1200 x 3000 pixels. View the monitors in a
darkened room with the screen brightness set lower and the contrast set
relatively high. That allows the subtle gradations of color to be seen
better, and the range of light to dark to include a maximum of monitor
produced gradations of brightness.

I've reserved discussion of electronic pixels and displayed pixels for
another time.

Returning to the background color gradations: In Photoshop the muted
background color may then be substituted for the color black, or other dark
background color throughout the file. The RGB values for black would be,
255, 255, 255, and for a dark blue-gray, say, 51, 51, 100. You can choose
other values in Photoshop.

The background color substitution technique will produce a deep outer space
color background effect instead of a black background. The color selected
to replace the black or near-black color should be relatively dark and
muted. A deep subdued violet, dull navy blue, or gray blue may be appropriate.

The way that the new colors work is that a bright point of light or color,
e.g., 255, 255, 255, or white, when viewed against a black back ground, or
0, 0, 0, has a glow or irradiation effect when view by the eye. Its a
visual irradiation effect or glare that makes the brighter spot of light
appear larger against the black or ultra-dark background.

The new muted color background has more light output at each screen pixel
and has its own slightly muted visual irradiation effect at the boundary of
each brighter pixel. That balances out the irradiation effect on the
computer screen. The result is that the brighter pixels will appear to have
less glare and appear smaller. The effect is to create a finer and more
precise color image. Each tiny bright light screen pixel will seem to be
possibly 1/2 the size.

A disadvantage is that dark or black hydrogen or dust clouds, for example,
may be modified just as the background color is modified.

If the background color is made of a gradation of several dark colors and
is not a uniform black, several substitutions may need to be made for each
pixel hue. Gradations may require a lot of retouching work, and other
Photoshop techniques may be used.

Black skies may give way to rich dark muted blue or dark muted violet
skies. The result where fine bright objects are to be seen is a sharper
displayed image. The blackness of the nothing of space is changed (here
said for the sake of imaging), and the original data from the existing
objects remains unmodified.


Ralph Hertle
  #7  
Old January 29th 05, 01:51 AM
Ralph Hertle
external usenet poster
 
Posts: n/a
Default

HAVRILIAK wrote:
Olympus provides a free "Background Subtraction Kit" as an alternative
to flatfield exposures for CCD imaging. I download the kit into a know
folder and then click on the background.exe file and it rapidly
installs the routine. What shows up is a file with the same name. I
double (or single) click on the file and ir reinstalls itself. The
Figure of their application never shows up. Anyone familiar with this
routine, your help will be greately appreciated.



HAVRILIAK:

Photoshop can remove background data. One way is that one may identify one
of the background pixel colors, e.g., a deep black. and remove every
instance of that color in the file. A different color may be substituted
for the selected color. Do that for all selected background colors by
picking color pixel by color pixel. Those colors are also deleted or
substituted everywhere in the file including from the desired image data.

Stacking different images so processed should cancel out the deletions from
the intended image areas, and the background would be modified or appear clear.

Obviously, one may want to see the subtle gradations.......

.....................


I resubmitted this message to fix some typos. One more idea occurs.

I want to add that there is a computer technique that enhances the
sharpness of the figure in a relationship to the background image.

For example, I use MicroStation CAD in my work in architecture and product
designing. Instead of a black background color for the computer monitor
screen against which all line work is placed, I set the background color to
be a dark eye-ease school blackboard green, dark gray, or dark gray-blue.
These low saturation (muted) darker colors are about 25% on a scale of
0-255. 0 being black and 255 being the maximum intensity of the hue in an
RGB scale, for example.

A high resolution 24 or 32-bit color monitor and full color graphics (video
adapter) board is needed. This technique will not work with a monitor that
doesn't display 16.4 M colors (or 255^3) where each of the three RGB colors
has 255 degrees of intensity. That type of monitor and display board
produces the number of possible color gradations of 255^3 at each pixel.
That's the number of combinatorial possibilities of color at each displayed
pixel (255 x 255 x 255). That produces fine blends of color and subtle
color hue and intensity gradations.

My Monitors are IBM 21" P-260 CRTs that each have 1200 x 1600 displayed
pixels at full 32-bit color. The graphics board is an ATI FireGL3 8800 that
displays a hi-res HST image of a star field across the two monitors. That
image, however divided, is 1200 x 3000 pixels. View the monitors in a
darkened room with the screen brightness set lower and the contrast set
relatively high. That allows the subtle gradations of color to be seen
better, and the range of light to dark to include a maximum of monitor
produced gradations of brightness.

I've reserved discussion of electronic pixels and displayed pixels for
another time.

Returning to the background color gradations: In Photoshop the muted
background color may then be substituted for the color black, or other dark
background color throughout the file. The RGB values for black would be,
255, 255, 255, and for a dark blue-gray, say, 51, 51, 100. You can choose
other values in Photoshop.

The background color substitution technique will produce a deep outer space
color background effect instead of a black background. The color selected
to replace the black or near-black color should be relatively dark and
muted. A deep subdued violet, dull navy blue, or gray blue may be appropriate.

The way that the new colors work is that a bright point of light or color,
e.g., 255, 255, 255, or white, when viewed against a black back ground, or
0, 0, 0, has a glow or irradiation effect when view by the eye. Its a
visual irradiation effect or glare that makes the brighter spot of light
appear larger against the black or ultra-dark background.

The new muted color background has more light output at each screen pixel
and has its own slightly muted visual irradiation effect at the boundary of
each brighter pixel. That balances out the irradiation effect on the
computer screen. The result is that the brighter pixels will appear to have
less glare and appear smaller. The effect is to create a finer and more
precise color image. Each tiny bright light screen pixel will seem to be
possibly 1/2 the size.

A disadvantage is that dark or black hydrogen or dust clouds, for example,
may be modified just as the background color is modified.

If the background color is made of a gradation of several dark colors and
is not a uniform black, several substitutions may need to be made for each
pixel hue. Gradations may require a lot of retouching work, and other
Photoshop techniques may be used.

Black skies may give way to rich dark muted blue or dark muted violet
skies. The result where fine bright objects are to be seen is a sharper
displayed image. The blackness of the nothing of space is changed (here
said for the sake of imaging), and the original data from the existing
objects remains unmodified.


Ralph Hertle
  #8  
Old January 29th 05, 04:52 AM
HAVRILIAK
external usenet poster
 
Posts: n/a
Default

Keep in mind this is a Java app. As such, you need to install a Java
runtime engine on your computer before you can use the program. The


Thanks for your comments. I didn't keep in mind that this is Java routine
and I don't have Java on my PC. I did download subtract background, did find
it and ran it. What happened is that it installed itself and when I ran it, it
never gave me the operational window.
My problem is that I live just to the north of the Philadelphia border and
flat frames are insufficient because of skydomes every where I look. What I
liked about the routine is that you could select at least 16 background points,
curve fit to a polynomial I guess and normalize the image frame with respect to
the interpolated background. This makes a lot of sence to me but I have
avoided the use of Java so far.
  #9  
Old January 29th 05, 05:05 AM
HAVRILIAK
external usenet poster
 
Posts: n/a
Default

nstance of that color in the file. A different color may be substituted
for the selected color. Do that for all selected background colors by


Thaks a lot for your comments. I have used Picture Window for similar
purposes. Briefly, the procedure was to make an exposure near the image, then
remove the stars in the second image and use this as a template for a flat
field image. This method is tedious while the Olympus method is so much more
elegant.
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
The Gravitational Instability Theory on the Formation of the Universe Br Dan Izzo Policy 6 September 7th 04 09:29 PM


All times are GMT +1. The time now is 12:31 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 SpaceBanter.com.
The comments are property of their posters.