Started to work with the Duck and wizard tool. Here are my results of LAB and RGB treatment in CM. I was quite surprised that the picture with RGB adjustments seems better! I normaly never test RGB as I assume LAB will give better results.
The LAB picture has a slight green tint and it was more diffult to get the neutral correct compared with RGB mode. Used the marking on the duck foot for setting neutral.
Did you get same results? Why did I get this result?
Thomas
Duck
One of the things to check is the number of pixels in the sample. You can set CM to sample (YxY) pixels. If your setting is to big you might have trouble getting a consistent neutral as you will be including pixels you might not really want in the sample. The grey band is an excellent neutral.
Lab does have it's faults...If you want to work out the green you can pin the red side of the A curve and try to adjust out the cast that way. RGB will allow you to have multiple neutrals based on brightness. A definite strength...but adjusting in RGB can become a exercise in chasing your tail. Usually not the case but easy to do.
Greg
Lab does have it's faults...If you want to work out the green you can pin the red side of the A curve and try to adjust out the cast that way. RGB will allow you to have multiple neutrals based on brightness. A definite strength...but adjusting in RGB can become a exercise in chasing your tail. Usually not the case but easy to do.
Greg
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mikemeister_admin
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mikemeister_admin
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The LAB picture has a slight green tint and it was more diffult to get the neutral correct compared with RGB mode. Used the marking on the duck foot for setting neutral.
I took your image and tried to correct out the slight green cast using LAB. My approach was to try to keep the greens so I chose to adjust the red side of the A curve.
I also opened the image up a bit. It looks less gloomy...I know you have your "dark" moods.... ;D
You can load the ACV file using the "load button to see my correction.
Copy the ACV to the desktop, open your lab version of the image in CM, and click the load button. My corrections will be applied and you will see the curves.
Greg
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derekfountain
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Started to work with the Duck and wizard tool. Here are my results of LAB and RGB treatment in CM. I was quite surprised that the picture with RGB adjustments seems better! I normaly never test RGB as I assume LAB will give better results.
Did you get same results? Why did I get this result?
The business of "shadow, neutral and highlight" basically involves putting those 3 image points into an algorithm and CM then adjusting the curves, and hence the image, using the result of that algorithm. The algorithm is implemented differently for each colour space, and will therefore give slightly different results depending on which one you choose to use.
For example, the RGB version of the "shadow, neutral and highlight" algorithm can take more than one neutral point, which can be very useful in mixed light images (those come later in the course). The HSB version only seems able to adjust the B curve, and (if my interpretation of my results is right) will ignore the neutral point you give it entirely. Mike will explain exactly what's going on if anyone needs to know.
For now, don't worry too much about these differences. Stage 1 of my standard workflow is to do the shadow, neutral and highlight points, then click each colourspace selector in turn to see which looks best. Using Mk1 Eyeball and maybe the hue clock, I make this decision with no regard to what theoretically should be the most appropriate colourspace for the image. Once decided, I hit Apply, then immediately reopen CM and then and only then do I start thinking about which colourspace I should be working in.
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