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:<math>final.rgb=color.rgb / sqrt(max(color.r, max(color.g, color.b)));</math> 0<color.rgb<1. Function "sqrt()" is square root in programing language (HLSL). Function "max(,)" choosing bigger number from two numbers. Compressed luminance is good for adding weak and strong light and don't get overbright light; and weak light still be looking pretty strong alone. But then why need such things like light attenuation so perhaps better use normal HDR without compressed luminance. BTW sky light is blue, lamp light is yellow, together white, thats how they not overbirighting each over perhaps. <small><span class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Versatranitsonlywaytofly|Versatranitsonlywaytofly]] ([[User talk:Versatranitsonlywaytofly|talk]] • [[Special:Contributions/Versatranitsonlywaytofly|contribs]]) 14:13, 7 December 2011 (UTC)</span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot-->
::Funny thing is, that if there is 3x3 grid, then each of 9 squares getting 10 Watts light energy. And if light is at same distance, but 10 times stronger, then each of 9 squares of same 3x3 grid getting 10 times more energy and not 100 times! I don't know clear reason why decibels measured sometimes with square root and why in logarithm plot, but this reason must be very stupid. I even sow how in HDR there are tryings to use square. So actually big contrast like 1000:1 monitors say 255 colour is 3 times stronger than 128, and 128 is 3 times stronger than 64 and 64 is 3 times stronger than 32 and so on. And on normal (perhaps cheaper) contrast monitors like 300:1, the colour 255 is 2 times stronger than 128, and 128 is 2 times stronger than 64 and so on. For say really very big contrast monitors like 10000:1, the colour 255 is 5 times stronger than colour 128, and 128 is 5 times stronger than 64, and 64 is 5 times stronger than 32 and so on. Of course there can be, that such big contrast like 100000:1 can mean, that 255 is 100000 times stronger than 0 and not than 1. But you know how with those LCD colours, if there is strong led light behind, then you get strong and 0 and 1, at least it should be in most cases, but who knows, maybe really 1 can be 10-1000 times stronger than 0 and this is the whole point and quality of big contrast ratio monitors. From here not hard to see the whole point of contrast ratio of monitors. It depends in what contrast ratio videocamera recoreder recording, I mean, how much times 1 is weaker than 255. Or is it about 300 times weaker or 1000 or 10000, because colours will be wrong and textures if they not match each over. <small><span class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Versatranitsonlywaytofly|Versatranitsonlywaytofly]] ([[User talk:Versatranitsonlywaytofly|talk]] • [[Special:Contributions/Versatranitsonlywaytofly|contribs]]) 22:11, 8 December 2011 (UTC)</span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot-->
::If you have monitor (with big contrast like 4^8=65536:1), where 255 is 4 times stronger than 128, and 128 is 4 times stronger than 64, and 64 is 4 times stronger than 32 and so on. Then by rising gamma to value <math>k_g=2</math>, an algorithm "<math>final.rgb=(color.rgb)^{1/2};</math> 0<color.rgb<1
::If you have monitor (with big contrast like 8^8=16777216:1), where 255 is 8 times stronger than 128, and 128 is 8 times stronger than 64, and 64 is 8 times stronger than 32 and so on. Then by rising gamma to value <math>k_g=3</math> you applying algorithm "<math>final.rgb=(color.rgb)^{1/3}; </math> 0<color.rgb<1
::For monitors with contrast 2^8=256~300:1, there is no point use gamma correction, because 1 (and even 0) shining pretty strong. So if monitors developers don't put they own calibration into monitor (that 0 is 1000 times weaker than 1 and 1 is about 300 times weaker than 255), then gamma should perfectly to let you to choose desired contrast ratio (from say 50:1 to 100000:1) by changing coefficient <math>0.5<k_g<0<3.5.</math> Good thing about gamma is that it don't rising 0 at all. So this is main advantage of big contrast monitors over small contrast monitors (which have strong 0 and contrast between 0 and is about 2:1 or at most 10:1), because if 0 is very black, then better visible weak colours like 3, 5, 10, if gamma is more than 1 (default gamma=1). But for some reason at least for old some CRT monitors contrast and brightness combined correction "contrast=100-brightness/2.55" rising too weak colours better and in correct contrast (you must judge if contrast between colours is correct by comparing 10 with 20 and 255 with 128 or 10 with 5, and if in all cases two times smaller number looks like two times weaker then contrast is correct, by correcting with gamma for some reason disappearing difference between 255 and 128 and difference between 5 and 10 is very big and between 10 and 20 very small, but it's maybe because in CRT (cathode ray tube) monitors screen becoming too negative and for weak colours it's big difference and for strong colours almost no difference, also after some times (after about 20 minutes) in CRT monitors screen becoming charged and weak colours becoming weaker; so for LCD monitors gamma should do everything correct). This contrast and brightness combined correction "contrast=100-brightness/2.55" difference between weak colours doing almost invisible; if before this correction colour was 10 was two times stronger than 5, then after correction colour 10 is 1.1 time stronger than 5, but for strong colours almost nothing changing, like if 128 was 2 times stronger than 64, then after correction 128 is 1.9 times stronger than 64. <small><span class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Versatranitsonlywaytofly|Versatranitsonlywaytofly]] ([[User talk:Versatranitsonlywaytofly|talk]] • [[Special:Contributions/Versatranitsonlywaytofly|contribs]]) 19:25, 12 December 2011 (UTC)</span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot-->
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