Open Macromedia Flash 8 and create a new flash document.
In the Property inspector, change your document size to 1600 x 1195 pixels.
Click on File > Import > Import to Stage
Import RGB – Red.jpg
In the property inspector, change the images x and y locations to 0, to align the image with the top left of your document.
In the timeline, click on ‘Show Frame’ or ‘Show All’ so that all of the picture is visible in the window.
Double click on the ‘Layer 1’ and rename it to Red
Add a new Layer and name it Green.
Click on File > Import > Import to Stage
Import RGB – Green.jpg
In the property inspector, change the images x and y locations to 0, to align the image with the top left of your document.
Add a new Layer and name it Blue.
Click on File > Import > Import to Stage
Import RGB – Blue.jpg
In the property inspector, change the images x and y locations to 0, to align the image with the top left of your document.
Click on the blue image, then press F8 on your keyboard to convert the image to a symbol.
Name the symbol ‘Blue’ and leave it as a movie clip type.
This is so that we can change the alpha channel of the image.
In the timeline, on the Blue Layer, click on the dot below the eye to hide the blue layer.
Now click on the Green image and press F8 on your keyboard to convert the image to a symbol.
Name the symbol ‘Green’ and leave it as a movie clip type.
We don’t need to change anything on the Red layer, so it can be left alone.
With the green image still selected change the alpha to 50% in the Property Inspector.
Click on the dot below the eye on the blue layer again to make it visible.
Select the blue image and change the alpha to 30%.
You have successfully mixed the Red Green and Blue channels to re-create the original image.
