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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
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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
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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
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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 |
#6
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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
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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
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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
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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. |
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