[argyllcms] Re: using Lab readings instead of a supported reader
- From: dmg <dmg@xxxxxxx>
- To: argyllcms@xxxxxxxxxxxxx
- Date: Sat, 27 Nov 2010 02:29:43 -0800
Hi Konstantin, everybody,
I have been trying to learn about color profiling in the last days,
trying to understand why I got these values.
My colorchecker came with a list of values for each patch. For
example, the last one (24) is 20.461, -0.079, -0.973 (CIE L*a*b).
I just retried the reading (several times) and I get a value that
fluctuates slightly (e.g 21.56, 0.84, -0.38) for a difference of
around 1.5 deltaE (using
http://www.brucelindbloom.com/index.html?ColorDifferenceCalcHelp.html).
My target is a passport one. My large colorchecker gives slightly
different readings. (e.g. 21.86, 0.14, -0.50). I suspect the crappy
values below were due to the fact that I measured them
under very strong sunlight (behind a window), but to be honest, that
is just speculation. It might be that I didn't know what I was doing.
Here is another set of values. This also shows the internal format in
which spyder3 saves its data. The first number is the patch number (as
read), then the Lab values. Each patch is repeated 4 times.
I have only included a section of the file.
<LabColor>46 3937 1316 1518</LabColor>
<LabColor>47 3940 1341 1527</LabColor>
<LabColor>48 3939 1338 1525</LabColor>
<LabColor>49 3939 1330 1521</LabColor>
<LabColor>50 6485 2055 1690</LabColor>
<LabColor>51 6486 2059 1692</LabColor>
<LabColor>52 6469 2083 1693</LabColor>
<LabColor>53 6471 2087 1694</LabColor>
<LabColor>54 5012 -341 -2243</LabColor>
<LabColor>55 5007 -359 -2240</LabColor>
<LabColor>56 5008 -352 -2246</LabColor>
<LabColor>57 5007 -361 -2249</LabColor>
<LabColor>58 4444 -1778 2445</LabColor>
<LabColor>59 4446 -1758 2430</LabColor>
<LabColor>60 4441 -1757 2437</LabColor>
<LabColor>61 4445 -1783 2447</LabColor>
<LabColor>62 5540 918 -2497</LabColor>
<LabColor>63 5553 925 -2485</LabColor>
<LabColor>64 5532 919 -2492</LabColor>
<LabColor>65 5531 929 -2493</LabColor>
<LabColor>66 7073 -3272 2</LabColor>
<LabColor>67 7065 -3259 -1</LabColor>
<LabColor>68 7054 -3250 -2</LabColor>
<LabColor>69 7021 -3025 39</LabColor>
<LabColor>70 6307 3466 6040</LabColor>
<LabColor>71 6341 3429 6020</LabColor>
<LabColor>72 6300 3517 6079</LabColor>
<LabColor>73 6316 3481 6090</LabColor>
<LabColor>74 4010 874 -4455</LabColor>
<LabColor>75 4005 887 -4482</LabColor>
<LabColor>76 4002 875 -4451</LabColor>
<LabColor>77 4012 884 -4498</LabColor>
<LabColor>78 5147 4707 1622</LabColor>
<LabColor>79 5142 4714 1634</LabColor>
<LabColor>80 5158 4697 1621</LabColor>
<LabColor>81 5050 4414 1614</LabColor>
<LabColor>82 3153 2303 -2062</LabColor>
<LabColor>83 3119 2205 -2097</LabColor>
<LabColor>84 3154 2244 -2048</LabColor>
<LabColor>85 3153 2235 -2052</LabColor>
<LabColor>86 7356 -2996 6457</LabColor>
<LabColor>87 7408 -2353 5869</LabColor>
<LabColor>88 7424 -2398 5871</LabColor>
<LabColor>89 7419 -2366 5865</LabColor>
<LabColor>90 7283 1705 7034</LabColor>
<LabColor>91 7276 1701 7039</LabColor>
<LabColor>92 7291 1691 7051</LabColor>
<LabColor>93 7268 1698 7026</LabColor>
<LabColor>94 2942 1197 -4913</LabColor>
<LabColor>95 2954 1186 -4901</LabColor>
<LabColor>96 2947 1207 -4865</LabColor>
<LabColor>97 2960 1196 -4867</LabColor>
<LabColor>98 5558 -3857 3208</LabColor>
<LabColor>99 5548 -3858 3218</LabColor>
<LabColor>100 5563 -3893 3233</LabColor>
<LabColor>101 5521 -4235 3300</LabColor>
<LabColor>102 4394 5281 2995</LabColor>
<LabColor>103 4399 5291 3004</LabColor>
<LabColor>104 4388 5292 3035</LabColor>
<LabColor>105 4388 5297 3037</LabColor>
<LabColor>106 8267 251 8229</LabColor>
<LabColor>107 8280 243 8260</LabColor>
<LabColor>108 8337 218 8302</LabColor>
<LabColor>109 8313 236 8276</LabColor>
<LabColor>110 5286 5318 -1331</LabColor>
<LabColor>111 5283 5290 -1329</LabColor>
<LabColor>112 5323 5320 -1327</LabColor>
<LabColor>113 5315 5332 -1337</LabColor>
<LabColor>114 5025 -2902 -2821</LabColor>
<LabColor>115 4983 -2841 -2791</LabColor>
<LabColor>116 5035 -2923 -2817</LabColor>
<LabColor>117 5038 -2892 -2812</LabColor>
<LabColor>118 9613 118 196</LabColor>
<LabColor>119 9631 82 201</LabColor>
<LabColor>120 9611 134 195</LabColor>
<LabColor>121 9650 88 201</LabColor>
<LabColor>122 8146 28 48</LabColor>
<LabColor>123 8143 25 50</LabColor>
<LabColor>124 8163 5 53</LabColor>
<LabColor>125 8155 34 51</LabColor>
<LabColor>126 6717 -2 10</LabColor>
<LabColor>127 6650 -298 -11</LabColor>
<LabColor>128 6720 -11 13</LabColor>
<LabColor>129 6726 -24 15</LabColor>
<LabColor>130 5094 39 65</LabColor>
<LabColor>131 5079 24 67</LabColor>
<LabColor>132 5077 32 75</LabColor>
<LabColor>133 5079 27 67</LabColor>
<LabColor>134 3650 -36 -64</LabColor>
<LabColor>135 3640 -35 -50</LabColor>
<LabColor>136 3658 -56 -49</LabColor>
<LabColor>137 3660 -63 -48</LabColor>
<LabColor>138 2107 2 -17</LabColor>
<LabColor>139 2095 52 -39</LabColor>
<LabColor>140 2162 81 32</LabColor>
<LabColor>141 2160 56 -1</LabColor>
2010/11/7 Konstantin Pyanzin <kokap@xxxxxxx>:
> BTW your results are very bad.
> Look at last 6 (grey) patches in the list. a* and b* should be near 0.
>
> Best regards,
>
> Sun, 07 Nov 2010 12:26:17 -0800 D M German wrote:
>>
>> I recently bought a Spyder3 print SR, and I would like to use Argyll
>> (the price was right). My understanding is that it is not supported
>> hardware. The software stores the data files as XML, and supports the
>> ability to export them as a list of Lab values.
>>
>> For example, these are the readings from a Gretag Color Checker:
>>
>> 34.75 10.26 10.86
>> 57.88 16.14 10.88
>> 44.99 -4.81 -24.35
>> 39.87 -19.49 20.12
>> 49.78 6.62 -27.39
>> 63.92 -33.52 -4.05
>> 56.46 29.44 52.01
>> 36.02 7.10 -44.72
>> 45.54 41.91 10.49
>> 27.89 19.76 -22.10
>> 67.10 -26.73 51.18
>> 65.63 10.74 62.01
>> 26.61 10.55 -48.13
>> 50.15 -39.35 27.41
>> 37.60 45.41 22.75
>> 74.89 -2.88 73.12
>> 47.07 47.61 -17.40
>> 45.50 -28.36 -29.45
>> 87.05 -3.50 -4.29
>> 73.24 -3.20 -5.05
>> 60.20 -3.00 -4.59
>> 45.39 -2.24 -3.19
>> 32.41 -2.40 -3.34
>> 18.94 -0.74 -2.18
>>
>>
>> Is it possible to use such readings to use the rest of the tools?
>>
>> Thanks a lot for any help.
>>
>> --dmg
>>
>>
>>
>>
>>
>>
>>
>> --
>> --
>> Daniel M. German
>> http://turingmachine.org/
>> http://silvernegative.com/
>> dmg (at) uvic (dot) ca
>> replace (at) with @ and (dot) with .
>
>
>
--
--dmg
---
Daniel M. German
http://turingmachine.org
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