View source for GIMP/C2/Adjusting-Colours-Using-Layers/English-timed

{| border = 1

|'''Time'''

|'''Narration'''


|-
| 00.22
| Welcome to Meet the Gimp. My name is Rolf Steinort and I’m recording this in Bremen, Northen Germany. 


|-
| 00.29
|In the previous edition I got this image here after editing

|-
| 00.33
|And today I think I should do something to set the colors. 

|-
| 00.39
| Because this image is too green.


|-
| 00.41
|There are lot of ways to adjust the color and one of them is the Curve Tool. 

|-
| 00.47
|I click on the curves tool in tool box and then I select the green channel and pull the curve down. 

|-
| 00.55
|Now you can see that the colour channels and the fog in the image looks like the real fog. 


|-
| 01.02
|Now, I have to adjust the curve in such a way that I get an image which is gray and not green or magenta. 

|-
| 01.13
|I don’t want to use curves tool because it damages the details of the image and I can’t correct the damage afterwards 

|-
| 01.23
|I could use the undo tool but I’ll have to redo all the steps after that.

|-
| 01.28
|So I want to have something that’ll not damage the image and I can adjust later on.

|-
|01.34
| There is such a way which uses a simple filter with layers

|-
|01.39
|So I have open here the layer dialog.
|-
|01.43
| You’ll see here background which is our original image.

|-
|01.47
| And I simply add a new layer and I select white in Layer Fill Type and give it a name, color correction green. 

|-
|01.59
|Now my image is fully white but I can change the layer mode.  

|-
|02.05
|The layer mode is an algorithm which combines the two layers i.e the original background layer and the newly created layer.

|-
|02.16
|So I choose here the Multiple mode.  

|-
| 02.22
|And you get the original image back as it was before. 

|-
| 02.27
|The Multiply mode, multiplies the pixels from the background to the pixels from the foreground, and divides the result by 255. 

|-
| 02.37
|And in a white picture all the color channels are 255, so multiplying by 255 and dividing by 255 gives the starting point i.e. Background


|-
| 02.52
| But if I reduce one channel in the new layer, it will be reduced in the background also because multiplying by say 200 and dividing by 255 gives less.  

|-
| 03.06
|Now i want to select such a color which has a reduced green channel. 

|-
| 03.12
|Here I have black as foreground colour, which i  change to background colour and white as foreground colour and you can see that red, green & blue all colour channels have same value i.e 255. 


|-
| 03.31
|By the way don’t be distracted by the colours on the slider here.

|-
| 03.36
| This is not blue, this is yellow but when I slide this down to a certain point, you see that colours in all the slider change automatically. 

|-
| 03.50
|Ok I select the green slider here and pull the slider to say something around 211.


|-
| 03.59
| And I pull the colour which I got as my foreground colour into my image and I get the result which is way to magenta. 

|-
| 04.10
|But  I can adjust the intensity of my green reduction with the help of the opacity slider.

|-
| 04.19
| And when I go back to zero I get the old image, and when I pull the slider up I can reduce the green channel in the image and also avoid getting magenta into the image. 

|-
| 04.35
| I think this looks quite good. 

|-
| 04.38
|By using the layers tool I can do changes anytime I want to and also I can do fine adjustments when more layers are stacked onto it and the change will stay even if I change something in underlying picture.


|-
| 04.55
| There are still changes to be made in this layer as now it appears gray and I want to add a bit of blue. 


|-
|05.03
|Again I follow the same procedure and make a new layer and called it color correction blue.

|-
|05.11
| And now I want to add a little bit of blue. 

|-
|05.15
|For adding blue in the image, I use the Screen mode which is a little bit more complicated than Multiply mode. 

|-
|05.24
|In screen mode the colors are 1st inverted and then multiplied and divided and quite complicated. 

|-
| 05.33
|Let me change the foreground colour to black and add the colour  i want to add directly and now I have to add a little bit of blue

|-
| 05.43
| So slide down the blue slider a bit.

|-
| 05.47
| And drag the colour into the image.

|-
| 05.51
|This here is supposed to be blue, which looks still like black but it is very dark blue.

|-
| 05.59
| Look at the image here and when I switch this off, you see the change

|-
| 06.04
| The image is definitely bluish.

|-
| 06.08
|I can switch off both the new layers and by that you get the starting point. 

|-
| 06.13
|When I click on the 1st layer we see the reduced channel of green and when I click on 2nd layer it adds a bit blue colour. 

|-
| 06.22
| I think this is too much blue so I reduce the opacity.  

|-
| 06.27
|I think this looks good.

|-
| 06.30
| I can adjust it later on all the time. 

|-
| 06.33
|The layer tool is very powerful because you can create layer upon layers and in each layer you can change the pixels which are coming up from the lower layer 

|-
| 06.44
| Possibilities of doing the correction is limitless and you can do it whenever you want.

|-
| 06.51
|Perhaps here you can slide the opacity slider a bit down to get a good colour and you can play with these sliders which gives real hand full of possibilities to change the color here. 


|-
| 07.05
|I think I have to cover the layer tool in detail on a special show but for today this is enough. 

|-
| 07.13
|This is Hemant Waidande dubbing for the Spoken Tutorial project and I hope to see you around next time.