Visual calibration target set method

Abstract

A novel process of visual calibration of a computer display or the like in volves adjusting the appearance and relative appearance of targets and su targets displayed on the display. An objective method is provided for determining the precisely optimal brightness setting for CRT displays, which method is also applicable to the setting of the “Black Level” control on some FPDs. A precise method is provided to visually determine conformity of a display's tonality to a given standard tone curve, for example a gamma 1.8 curve, which is embodied in one of the preferred calibration target sets. The need to sense and therefore be able to control and to verify the correct gray balance of the entire tone scale of the display is met. The problem of verifying the similarity of the tone curve in the display profile and that of the actual calibration is solved. By converting a preferred RGB gamma target into CIE Lab image data through an ideal display profile of the correct gamma, a new kind of target is taught.

1. An apparatus for calibrating a display associated with stored Lookup Tables, including:
 first means for displaying on said display a first midtone sub-target having a first midtone solid adjacent to a first midtone blended region, said first midtone blended region having a first series of adjacent double rows of substantially black pixels alternating with a first series of single rows of light pixels;    second means for displaying on said display a second dark sub-target having a second dark solid adjacent to a second dark blended region, said second dark blended region having a second series of adjacent double rows of substantially black pixels alternating with a second series of single rows of midtone pixels;    third means for displaying on said display a third light sub-target having a third light solid adjacent to a third fight blended region, said third light blended region having a third series of single rows of substantially black pixels alternating with a third series of single rows of midtone pixels and alternating with a third series of single rows of light pixels; and    means for modifying said Lookup Tables responsive to changes in said first, second and third sub-targets.    
     
     
       2. The apparatus of  claim 1  wherein:
 said first midtone solid is midtone gray and said first series of single rows of light pixels are white,  
 said second dark solid is dark gray and said second series of single rows of midtone pixels are midtone gray, and  
 said third light solid is light gray and said third series of single rows of midtone pixels are midtone gray and said third series of single rows of light pixels are white.  
 
     
     
       3. The apparatus of  claim 2  further including:
 means for displaying on said display a gray scale, and wherein  
 said second dark solid is three-quartertone gray and said third light solid is quartertone gray.  
 
     
     
       4. The apparatus of  claim 1  wherein:
 said first midtone solid is midtone red and said first series of single rows of light pixels are light red,  
 said second dark solid is dark red and said second series of single rows of midtone pixels are midtone red, and  
 said third light solid is light red, said third series of single rows of midtone pixels are midtone red and said third series of single rows of light pixels are light red.  
 
     
     
       5. The apparatus of  claim 4  further including:
 means for displaying on said display a fourth lined blended-region-and-solid dark green sub-target;  
 means for displaying on said display a fifth lined blended-region-and-solid midtone green sub-target;  
 means for displaying on said display a sixth lined blended-region-and-solid light green sub-target;  
 means for displaying on said display a seventh lined blended-region-and-solid dark blue sub-target;  
 means for displaying on said display a eighth lined blended-region-and-solid midtone blue sub-target;  
 means for displaying on said display a ninth lined blended-region-and-solid light blue sub-target; and wherein  
 said means for modifying said LookUp Tables responsive to changes in said first, second and third sub-targets is also responsive to changes in said fourth through ninth sub-targets.  
 
     
     
       6. The apparatus of  claim 1  wherein:
 said first midtone solid is midtone green and said first series of single rows of light pixels are light green,  
 said second dark solid is dark green and said second series of single rows of midtone pixels are midtone green, and  
 said third light solid is light green, said third series of single rows of midtone pixels are midtone green and said third series of single rows of light pixels are light green.  
 
     
     
       7. The apparatus of  claim 6  further including:
 means for displaying on said display a fourth lined blended-region-and-solid dark red sub-target;  
 means for displaying on-said display a fifth lined blended-region-and-solid midtone red sub-target;  
 means for displaying on said display a sixth lined blended-region-and-solid light red sub-target;  
 means for displaying on said display a seventh lined blended-region-and-solid dark blue sub-target;  
 means for displaying on said display a eighth lined blended-region-and-solid midtone blue sub-target;  
 means for displaying on said display a ninth lined blended-region-and-solid light blue sub-target; and wherein  
 said means for modifying said LookUp Tables responsive to changes in said first, second and third sub targets is also responsive to changes in said fourth through ninth sub-targets.  
 
     
     
       8. The apparatus of  claim 1  wherein:
 said first midtone solid is midtone blue and said first series of single rows of light pixels are light blue,  
 said second dark solid is dark blue and said second series of single rows of midtone pixels are midtone blue, and  
 said third light solid is light blue, said third series of single rows of midtone pixels are midtone blue and said third series of single rows of light pixels are light blue.  
 
     
     
       9. The apparatus of  claim 8  further including:
 means for displaying on said display a fourth lined blended-region-and-solid dark green sub-target;  
 means for displaying on said display a fifth lined blended-region-and-solid midtone green sub-target;  
 means for displaying on said display a sixth lined blended-region-and-solid light green sub-target;  
 means for displaying on said display a seventh lined blended-region-and-solid dark red sub-target;  
 means for displaying on said display a eighth lined blended-region-and-solid midtone red sub-target;  
 means for displaying on said display a ninth lined blended-region-and-solid light red sub-target; and wherein  
 said means for modifying said LookUp Tables responsive to changes in said first, second and third sub-targets is also responsive to changes in said fourth through ninth sub-targets.  
 
     
     
       10. An apparatus for calibrating a display associated with stored LookUp Tables, including:
 first means for displaying on said display a first blended-region-and-solid midtone sub-target;    second means for displaying on said display a second blended-region-and-solid light sub-target;    third means for displaying on said display a third blended-region-and-solid dark sub target, said third dark sub-target having a third dark solid surrounded by a uniform repeating pattern of between one and three white pixels per first group of twelve pixels, the remainder of said first group of twelve pixels being substantially black pixels; fourth means for displaying on said display a fourth blended-region-and-solid very dark sub-target, said fourth very dark sub-target having a fourth very dark solid surrounded by a uniform repeating pattern of between one and three midtone gray pixels per second group of twelve pixels, the remainder of said second group of twelve pixels being substantially black pixels; and    means for modifying said LookUp Tables responsive to changes in said first, second, third and fourth sub-targets.    
     
     
       11. An apparatus for calibrating a display including:
 means for displaying on said display a first brightness tone solid having a first dark tone;    means for displaying on said display a second brightness tone solid having a second dark tone;    means for displaying on said display a third brightness tone solid having a third dark tone; and    means for calibrating the brightness of said display by adjusting the relative lightnesses of said brightness tone solids until a first visible degree of lightness difference between a first two of said brightness tone solids substantially equals a second visible degree of lightness difference between a second two of said brightness tone solids.    
     
     
       12. The apparatus of  claim 11  further including:
 means for displaying on said display a fourth brightness tone solid having a fourth dark tone, said first brightness tone solid displayed adjacent to said second brightness tone solid and said third brightness tone solid displayed adjacent to said fourth brightness tone solid, 
 wherein said means for calibrating said brightness of said display calibrates by adjusting the relative lightnesses of said brightness tone solids until a first visible degree of lightness difference between said first and second brightness tone solids substantially equals a second visible degree of lightness difference between said third and fourth brightness tone solids.  
 
 
     
     
       13. The apparatus of  claim 12  further including:
 overall slider means for controlling the full tone scale on said display;  
 darks slider means for controlling the dark half of the tone scale on said display;  
 lights slider means for controlling the light half of the tone scale on said display; first means for displaying on said display at least one first lined blended-region-and-solid gamma sub-target responsive to adjustments of said overall slider means;  
 second means for displaying on said display at least one second lined blended-region-and-solid gamma sub-target responsive to adjustments of said darks slider means;  
 third means for displaying on said display at least one third lined blended-region-and-solid gamma sub-target responsive to adjustments of said lights slider means; and  
 means for calibrating the gamma of said display responsive to changes in said gamma sub targets occasioned by adjustments to said overall slider means, darks slider means and lights slider means.  
 
     
     
       14. The apparatus of  claim 13  wherein:
 the first, second and third displaying means display a total of eight first, second and third lined blended-region-and-solid gamma sub-targets.  
 
     
     
       15. A system for calibrating a display, including:
 a gray balance target produced by said display having at least three blended-region-and-solid gray balance sub-targets and a gray scale;    a brightness target produced by said display having at least a first brightness tone solid having a first dark tone, a second brightness tone solid having a second dark tone, and a third brightness tone solid having a third dark tone;    a gamma target produced by said display having eight lined blended-region-and-solid gamma sub-targets;    at least one target adjustment tool produced by said display; and    a video card having LookUp Tables responsive to changes in said gray balance target, said brightness target and said gamma target.    
     
     
       16. The system of  claim 15  wherein:
 said gray balance target includes 
 a first midtone sub-target having a first midtone solid adjacent to a first midtone blended region, said first midtone blended region having a first series of adjacent double rows of substantially black pixels alternating with a first series of single rows of light pixels;  
 a second dark sub-target having a second dark solid adjacent to a second dark blended region, said second dark blended region having a second series of adjacent double rows of substantially black pixels alternating with a second series of single rows of midtone pixels; and  
 a third light sub-target having a third light solid adjacent to a third light blended region, said third light blended region having a third series of single rows of substantially black pixels alternating with a third series of single rows of midtone pixels and alternating with a third series of single rows of light pixels.  
 
 
     
     
       17. The system of  claim 16  wherein:
 said first midtone solid is midtone gray and said first series of single rows of light pixels are white,  
 said second dark solid is dark gray and said second series of single rows of midtone pixels are midtone gray, and  
 said third light solid is light gray and said third series of single rows of midtone pixels are midtone gray and said third series of single rows of light pixels are white.  
 
     
     
       18. A method for calibrating a display including the steps of:
 providing LookUp Tables associated with said monitor;    providing a first midtone sub-target having a first midtone solid adjacent to a first midtone blended region, said first midtone blended region having a first series of adjacent double rows of substantially black pixels alternating with a first series of single rows of light pixels;    providing a second dark sub-target having a second dark solid adjacent to a second dark blended region, said second dark blended region having a second series of adjacent double rows of substantially black pixels alternating with a second series of single rows of midtone pixels;    providing a third light sub-target having a third light solid adjacent to a third light blended region, said third light blended region having a third series of single rows of substantially black pixels alternating with a third series of single rows of midtone pixels and alternating with a third series of single rows of light pixels;    adjusting the visual appearance of said first midtone sub-target until said first midtone solid appears to blend with said first midtone blended region;    adjusting the visual appearance of said second dark sub-target until said second dark solid appears to blend with second dark blended region;    adjusting the visual appearance of said third light sub-target until said third fight solid appears to blend with said third light blended region; and    saving modifications to said LookUp tables which have occurred as a result of any of the preceding steps.    
     
     
       19. The method of  claim 18  further including the steps of:
 providing a first brightness tone solid having a first dark tone;  
 providing a second brightness tone solid having a second dark tone;  
 providing a third brightness tone solid having a third dark tone,  
 providing a fourth brightness tone solid having a fourth dark tone, said first brightness tone solid displayed adjacent to said second brightness tone solid and said third brightness tone solid displayed adjacent to said fourth brightness tone solid; and  
 calibrating the brightness of said display by adjusting the relative lightnesses of said brightness tone solids until a first visible degree of lightness difference between said first and second brightness tone solids substantially equals a second visible degree of lightness difference between said third and fourth brightness tone solids.  
 
     
     
       20. The method of  19  further including the steps of:
 providing at least one first lined blended-region-and-solid gamma sub target responsive to adjustments in the full tone scale on said display;  
 providing at least one second lined blended-region-and-solid gamma sub-target responsive to adjustments in the dark half of the tone scale on said display;  
 providing at least one third lined blended-region-and-solid gamma sub-target responsive to adjustments in the light half of the tone scale on said display;  
 adjusting said at least one first lined blended-region-and-solid gamma sub-target until it appears fully blended visually;  
 adjusting said at least one second lined blended-region-and-solid gamma sub-target until it appears fully blended visually; and  
 adjusting said at least one third lined blended-region-and-solid gamma sub-target until it appears filly blended visually.  
 
     
     
       21. An apparatus for calibrating a display associated with stored LookUp Tables, including:
 first means for displaying on said display a first midtone sub-target having a first midtone solid adjacent to a first midtone blended region, said first midtone blended region having a first mixture of substantially black pixels and light pixels;    second means for displaying on said display a second blended-region-and-solid dark sub-target;    third means for displaying on said display a third blended-region-and-solid light sub-target;    overall tone means for adjusting said first midtone LookUp Tables responsive to changes in said first midtone sub-target;    dark tone means for adjusting said second dark sub-target and for modifying said LookUp Tables responsive to changes in said second dark sub-target; and    light tone means for adjusting said third light sub-target and for modifying said LookUp Tables responsive to changes in said third light sub-target.    
     
     
       22. The apparatus of  claim 21  wherein:
 said second dark sub-target has a second dark solid adjacent to a second dark blended region, said second dark blended region having a second mixture of substantially black pixels and midtone pixels, and  
 said third light sub-target has a third light solid adjacent to a third light blended region, said third light blended region having a third mixture of substantially black pixels, midtone pixels, and light pixels.  
 
     
     
       23. The apparatus of  claim 22  wherein:
 said first mixture is of substantially black pixels and white pixels, and  
 said third mixture is of substantially black pixels, midtone pixels, and white pixels.  
 
     
     
       24. The apparatus of  claim 21  wherein:
 said second dark sub-target has a second dark solid adjacent to a second dark blended region, said second dark blended region having a second mixture of substantially black pixels and light pixels, and  
 said third light sub-target has a third light solid adjacent to a third light blended region, said third light blended region having a third mixture of pixels chosen from the tones black and midtone and of light pixels.  
 
     
     
       25. The apparatus of  claim 24  wherein:
 said first mixture is of substantially black pixels and white pixels,  
 said second mixture is of substantially black pixels and white pixels, and  
 said third mixture is of pixels chosen from the tones black and midtone and of white pixels.  
 
     
     
       26. The apparatus of  claim 22  further including:
 fourth means for displaying on said display a fourth very dark sub-target having a fourth very dark solid adjacent to a fourth very dark blended region, said fourth very dark blended region having a mixture of substantially black pixels and midtone pixels.  
 
     
     
       27. An apparatus for calibrating a display associated with stored LookUp Tables, said apparatus including:
   first means for displaying on said display a first sub-target having a first solid region comprising pixels of first uniform value, said first solid region being substantially adjacent to a first blended region, said first blended region comprising pixels of first alternating values including values which are both higher and lower than the value of the pixels of said first solid region, and said first alternating values including a value which is substantially the maximum and a value which is substantially the minimum;        second means for displaying on said display a second sub-target having a second solid region comprising pixels of second uniform value, said second solid region being substantially adjacent to a second blended region, said second blended region comprising pixels of second alternating values, including values which are both higher and lower than the value of the pixels of said second solid region, and further including at least one value which is neither substantially the minimum nor substantially the maximum; and        means for sequentially modifying said LookUp Tables so as to modify the appearance of said first and second sub-targets.     
     
     
       28. An apparatus for calibrating a display associated with stored LookUp Tables, said apparatus including:
   first means for displaying on said display a first sub-target having a first solid region comprising pixels of first uniform value, said first solid region being adjacent to a first blended region, said first blended region comprising pixels of first alternating values including values which are both higher and lower than the value of the pixels of said first solid region;        second means for displaying on said display a second sub-target having a second solid region comprising pixels of second uniform value, said second solid region being adjacent to a second blended region, said second blended region comprising pixels of second alternating values, including values which are both higher and lower than the value of the pixels of said second solid region, and further including at least one value which is neither substantially the minimum nor substantially the maximum;        means for sequentially modifying said LookUp Tables so as to modify the appearance of said first and second sub-targets;        first means of adjustment of the appearance of said first sub-target by modifying said LookUp Tables so as to facilitate the user to cause said first solid region to appear to visually blend with said first blended region;        second means of adjustment of the appearance of said second sub-target by modifying said LookUp Tables so as to facilitate the user to subsequently cause said second solid region to appear to visually blend with said second blended region;        where said blending of said first sub-target assures the validity for calibration of said second sub-target; and        where absent said blending of said first sub-target, said second blended region could not be assured of having the correct appearance against which to adjust the appearance of said second solid region so as to achieve accurate calibration at the point in the tone scale of said second solid region.     
     
     
       29. The apparatus of  claim 27  wherein:
   said first solid region comprises gray pixels;    
   said second solid region comprises gray pixels; and    
   said second alternating values include at least one value which is neither substantially black nor substantially white.   
 
     
     
       30. The apparatus of  claim 28  wherein:
   said first solid region comprises gray pixels;    
   said second solid region comprises gray pixels; and    
   said second alternating values include at least one value which is neither substantially black nor substantially white.   
 
     
     
       31. The apparatus of  claim 29  wherein:
   said second alternating values include at least one value which is substantially closer to the value of said first solid region than to either the value of white or the value of black.   
 
     
     
       32. The apparatus of  claim 30  wherein:
   said second alternating values include at least one value which is substantially closer to the value of said first solid region than to either the value of white or the value of black.   
 
     
     
       33. The apparatus of  claim 30  wherein:
   said second alternating values include at least one value which is substantially identical to the value of said first solid region.   
 
     
     
       34. The apparatus of  claim 27  wherein:
   said first solid region comprises gray pixels;    
   said first alternating values include both the value of a color which is substantially black and the value of a color which is substantially white;    
   said second solid region comprises gray pixels; and    
   said second alternating values include at least one value which is neither substantially black nor substantially white.   
 
     
     
       35. The apparatus of  claim 34  further including:
   first means of adjustment of the appearance of said first sub-target by modifying said LookUp Tables so as to facilitate the user to cause said first solid region to appear to visually blend with said first blended region by adjusting the gray balance and lightness of said first solid region;    
   second means of adjustment of the appearance of said second sub-target by modifying said LookUp Tables so as to facilitate the user to subsequently cause said second solid region to appear to visually blend with said second blended region by adjusting the gray balance and lightness of said first solid region;    
   where said blending of said first sub-target assures the validity for calibration of said second sub-target; and    
   where absent said blending of said first sub-target, said second blended region could not be assured of having the correct appearance against which to adjust the appearance of said second solid region so as to achieve accurate calibration at the point in the tone scale of said second solid region. [ 36 . The apparatus of  claim 29  wherein:  
   said second alternating values include at least one value which is substantially identical to the value of said first solid region.   
 
     
     
       37. The apparatus of  claim 35  wherein:
   said second alternating values include at least one value which is substantially identical to the value of said first solid region.   
 
     
     
       38. The apparatus of  claim 33  further including:
   third means for displaying on said display a third sub-target having a third solid region comprising gray pixels of third uniform value, said third solid region being substantially adjacent to a third blended region, said third blended region comprising pixels of third alternating values, including values which are both higher and lower than the value of the pixels of said third solid region, and further including at least one value which is substantially identical to the value of said second solid region; and    
   third means of adjustment of the appearance of said third sub-target so as to facilitate the user to subsequently cause said third solid region to appear to visually blend with said third blended region;    
   where said blending of said second sub-target assures the validity for calibration of said third sub-target; and    
   where absent said blending of said second sub-target, said third blended region could not be assured of having the correct appearance against which to adjust the appearance of said third solid region so as to achieve accurate calibration at the point in the tone scale of said third solid region.   
 
     
     
       39. The apparatus of  claim 32  further including:
   third means for displaying on said display a third sub-target having a third solid region comprising gray pixels of third uniform value, said third solid region being substantially adjacent to a third blended region, said third blended region comprising pixels of third alternating values, including values which are both higher and lower than the value of the pixels of said third solid region, and further including at least one value which is substantially closer to the value of said second solid region than to either the value of white or the value of black; and    
   third means of adjustment of the appearance of said third sub-target so as to facilitate the user to subsequently cause said third solid region to appear to visually blend with said third blended region;    
   where said blending of said second sub-target assures the validity for calibration of said third sub-target; and    
   where absent said blending of said second sub-target, said third blended region could not be assured of having the correct appearance against which to adjust the appearance of said third solid region so as to achieve accurate calibration at the point in the tone scale of said third solid region.   
 
     
     
       40. The apparatus of  claim 27  wherein:
   said first sub-target is a first red sub-target;    
   said first solid region is a first red solid region comprising red pixels of first uniform value;    
   said second sub-target is a second red sub-target;    
   said second solid region is a second red solid region comprising red pixels of second uniform value; and    
   said second alternating values include at least one value which is substantially closer to the value of said first solid region than to either the value of maximum red or the value of black.   
 
     
     
       41. The apparatus of  claim 40  wherein:
   said second alternating values include at least one value which is substantially identical to the value of said first solid region.   
 
     
     
       42. The apparatus of  claim 40  further including:
   third means for displaying on said display a third green sub-target having a third green solid region comprising green pixels of third uniform value, said third green solid region being substantially adjacent to a third blended region, said third blended region comprising pixels of third alternating values, including values which are both higher and lower than the value of the pixels of said third green solid region;    
   fourth means for displaying on said display a fourth green sub-target having a fourth green solid region comprising green pixels of fourth uniform value, said fourth green solid region being substantially adjacent to a fourth blended region, said fourth blended region comprising pixels of fourth alternating values, including values which are both higher and lower than the value of the pixels of said fourth green solid region, and further including at least one value which is substantially closer to the value of said third green solid region than to either the value of maximum green or the value of black;    
   fifth means for displaying on said display a fifth blue sub-target having a fifth blue solid region comprising blue pixels of fifth uniform value, said fifth blue solid region being substantially adjacent to a fifth blended region, said fifth blended region comprising pixels of fifth alternating values, including values which are both higher and lower than the value of the pixels of said fifth blue solid region;    
   sixth means for displaying on said display a sixth blue sub-target having a sixth blue solid region comprising blue pixels of sixth uniform value, said sixth blue solid region being substantially adjacent to a sixth blended region, said sixth blended region comprising pixels of sixth alternating values, including values which are both higher and lower than the value of the pixels of said sixth blue solid region, and further including at least one value which is substantially closer to the value of said fifth blue solid region than to either the value of maximum blue or the value of black; and    
   means for sequentially modifying said LookUp Tables so as to modify the appearance of said first red sub-target then subsequently modify the appearance of said second red sub-target, modify the appearance of said third green sub-target then subsequently modify the appearance of said fourth green sub-target, and modify the appearance of said fifth blue sub-target then subsequently modify the appearance of said sixth blue sub-target.   
 
     
     
       43. The apparatus of  claim 41  further including:
   third means for displaying on said display a third green sub-target having a third green solid region comprising green pixels of third uniform value, said third green solid region being substantially adjacent to a third blended region, said third blended region comprising pixels of third alternating values, including values which are both higher and lower than the value of the pixels of said third green solid region, and which third alternating values include values which are substantially maximum green and substantially black;    
   fourth means for displaying on said display a fourth green sub-target having a fourth green solid region comprising green pixels of fourth uniform value, said fourth green solid region being substantially adjacent to a fourth blended region, said fourth blended region comprising pixels of fourth alternating values, including values which are both higher and lower than the value of the pixels of said fourth green solid region, and further including at least one value which is which is substantially identical to the value of said third green solid region;    
   fifth means for displaying on said display a fifth blue sub-target having a fifth blue solid region comprising blue pixels of fifth uniform value, said fifth blue solid region being substantially adjacent to a fifth blended region, said fifth blended region comprising pixels of fifth alternating values, including values which are both higher and lower than the value of the pixels of said fifth blue solid region, and which fifth alternating values include values which are substantially maximum blue and substantially black;    
   sixth means for displaying on said display a sixth blue sub-target having a sixth blue solid region comprising blue pixels of sixth uniform value, said sixth blue solid region being substantially adjacent to a sixth blended region, said sixth blended region comprising pixels of sixth alternating values, including values which are both higher and lower than the value of the pixels of said sixth blue solid region, and further including at least one value which is which is substantially identical to the value of said fifth blue solid region; and    
   means for sequentially modifying said LookUp Tables so as to modify the appearance of said first red sub-target then subsequently modify the appearance of said second red sub-target, modify the appearance of said third green sub-target then subsequently modify the appearance of said fourth green sub-target, and modify the appearance of said fifth blue sub-target then subsequently modify the appearance of said sixth blue sub-target.   
 
     
     
       44. The apparatus of  claim 30  further including:
   saving modifications to said LookUp Tables which have occurred as a result of said user blending adjustments.   
 
     
     
       45. The apparatus of  claim 40  further including:
   first lightness adjustment of said first red solid region so as to cause it to match the apparent lightness of said first blended region;    
   subsequent second lightness adjustment of said second red solid region so as to cause it to match the apparent lightness of said second blended region; and    
   saving modifications to said LookUp Tables which have occurred as a result of said first and second lightness adjustments.   
 
     
     
       46. The apparatus of  claim 31  further including:
   first lightness and gray balance adjustment of said first solid region so as to cause it to match the apparent lightness and gray balance of said first blended region and therefore appear to blend;    
   subsequent second lightness and gray balance adjustment of said second solid region so as to cause it to match the apparent lightness and gray balance of said second blended region and therefore appear to blend; and    
   saving modifications to said LookUp Tables which have occurred as a result of said first and second lightness and gray balance adjustments.   
 
     
     
       47. The apparatus of  claim 36  further including:
   first lightness and gray balance adjustment of said first solid region so as to cause it to match the apparent lightness and gray balance of said first blended region and therefore appear to blend;    
   subsequent second lightness and gray balance adjustment of said second solid region so as to cause it to match the apparent lightness and gray balance of said second blended region and therefore appear to blend; and    
   saving modifications to said LookUp Tables which have occurred as a result of said first and second lightness and gray balance adjustments.   
 
     
     
       48. The apparatus for calibrating a display associated with stored LookUp Tables of  claim 27  further including:
   third means for displaying on said display a third sub-target having a third dark gray solid region comprising dark gray pixels of third uniform value, said third dark gray solid region being substantially adjacent to a third blended region, said third blended region comprising pixels of third alternating values in a third repeating pattern of light pixels and dark pixels, not more than one-fourth of the pixels of said third repeating pattern being light; and    
   means for modifying said LookUp Tables so as to modify the appearance of said third sub-target.   
 
     
     
       49. The apparatus of  claim 48  wherein:
   said third blended region comprises pixels of third alternating values in a third repeating pattern of substantially white pixels and substantially black pixels, not more than one-fourth of the pixels of said third repeating pattern being substantially white.   
 
     
     
       50. The apparatus for calibrating a display associated with stored LookUp Tables of  claim 27  further including:
   third means for displaying on said display a third sub-target having a third midtone-to-light-gray solid region comprising midtone-to-light-gray pixels of third uniform value, said third midtone-to-light-gray solid region being substantially adjacent to a third blended region, said third blended region comprising pixels of third alternating values in a third repeating pattern of dark pixels and light pixels, not more than one-third of the pixels of said third repeating pattern being dark, said third repeating pattern not being a pattern consisting exclusively of horizontal lines; and    
   means for modifying said LookUp Tables so as to modify the appearance of said third sub-target.   
 
     
     
       51. The apparatus of  claim 50  wherein:
   said third repeating pattern is a pattern of substantially black pixels and substantially white pixels, not more than one-third of the pixels of said first repeating pattern being substantially black.   
 
     
     
       52. The apparatus of  claim 27  wherein:
   said first solid region is a gray solid region comprising pixels of first uniform value;    
   said second sub-target is a dark sub-target;    
   said second solid region is a dark gray solid region;    
   said second blended region has a uniform repeating pattern of substantially midtone pixels and dark pixels, not more than one-fourth of the pixels of said first repeating pattern being substantially midtone; and    
   said first repeating pattern not being a pattern consisting exclusively of horizontal lines.   
 
     
     
       53. The apparatus of  claim 52  wherein said second blended region has a uniform repeating pattern of substantially midtone pixels and substantially black pixels, not more than one-fourth of the pixels of said first repeating pattern being substantially midtone. 
     
     
       54. The apparatus of  claim 27  wherein:
   said first solid region is a gray solid region comprising pixels of first uniform value;    
   said second sub-target is a light sub-target;    
   said second solid region is a light gray solid region;    
   said second blended region has a uniform repeating pattern of substantially midtone pixels and light pixels, not more than one-fourth of the pixels of said first repeating pattern being substantially midtone; and    
   said first repeating pattern not being a pattern consisting exclusively of horizontal lines.   
 
     
     
       55. The apparatus of  claim 54  wherein:
   said second blended region has a uniform repeating pattern of substantially midtone pixels and substantially white pixels.   
 
     
     
       56. An apparatus for verifying the calibration state of a display, said apparatus including:
   first means for displaying on said display a first red sub-target having a first solid region comprising pixels of first uniform red value, said first solid region being substantially adjacent to a first blended region, said first blended region comprising pixels of first alternating values including values which are both higher and lower than the value of the pixels of said first solid region, and which first alternating values include values which are substantially maximum red and substantially black; and        second means for displaying on said display a second red sub-target having a second solid region comprising pixels of second uniform red value, said second solid region being substantially adjacent to a second blended region, said second blended region comprising pixels of second alternating values including values which are both higher and lower than the value of the pixels of said second solid region, and further including at least one value which is substantially closer to the value of said first solid region than to either maximum red or black.     
     
     
       57. An apparatus for verifying the calibration state of a display, said apparatus including:
   first means for displaying on said display a first gray sub-target having a first gray solid region comprising pixels of first uniform value, said first solid region being substantially adjacent to a first blended region, said first blended region comprising pixels of first alternating values including values which are both substantially white and substantially black;        second means for displaying on said display a second gray sub-target having a second gray solid region comprising pixels of second uniform value, said second solid region being substantially adjacent to a second blended region, said second blended region comprising pixels of second alternating values comprising values which are both higher and lower than the value of the pixels of said second solid region, and further including at least one value which is substantially closer to the value of said first gray solid region than to either white or black; and        third means for displaying on said display a third gray sub-target having a third gray solid region comprising pixels of third uniform gray value, said third gray solid region being substantially adjacent to a third blended region, said third blended region comprising pixels of third alternating values including values which are both higher and lower than the value of the pixels of said third solid region and further including values which are both substantially white and substantially black.     
     
     
       58. The apparatus of  claim 57  wherein:
   said second alternating values include at least one value which is substantially identical to the value of said first solid region.   
 
     
     
       59. An apparatus for verifying the calibration state of a display, said apparatus including:
   first means for displaying on said display a first gray sub-target having a first gray solid region comprising pixels of first uniform value, said first solid region being substantially adjacent to a first blended region, said first blended region comprising pixels of first alternating values including values which are both white and black;        second means for displaying on said display a second gray sub-target having a second gray solid region comprising pixels of second uniform value, said second solid region being substantially adjacent to a second blended region, said second blended region comprising pixels of second alternating values comprising values which are both higher and lower than the value of the pixels of said second solid region, and further including at least one value which is substantially closer to the value of said first gray solid region than to either white or black; and        third means for displaying on said display a third gray sub-target having a third gray solid region comprising pixels of third uniform gray value, said third gray solid region being substantially adjacent to a third blended region, said third blended region comprising pixels of third alternating values including values which are both higher and lower than the value of the pixels of said third solid region and further including values which are both substantially closer to the value of said second gray solid region than to either white or black.     
     
     
       60. An apparatus for verifying the calibration state of a display, said apparatus including:
   first means for displaying on said display a first gray sub-target having a first gray solid region comprising pixels of first uniform value, said first solid region being substantially adjacent to a first blended region, said first blended region comprising pixels of first alternating values including values which are both substantially white and substantially black;        second means for displaying on said display a second gray sub-target having a second gray solid region comprising pixels of second uniform value, said second solid region being substantially adjacent to a second blended region, said second blended region comprising pixels of second alternating values comprising values which are both higher and lower than the value of the pixels of said second solid region, and further including at least one value which is substantially identical to the value of said first gray solid region; and        third means for displaying on said display a third gray sub-target having a third gray solid region comprising pixels of third uniform gray value, said third gray solid region being substantially adjacent to a third blended region, said third blended region comprising pixels of third alternating values including values which are both higher and lower than the value of the pixels of said third solid region and further including values which is substantially identical to the value of said second gray solid region.     
     
     
       61. The apparatus of  claim 60  wherein:
   said second alternating values include at least one value which is identical to the value of said first solid region.