Here is a way to create such kind of pictures :
step 1 - create an animation
Use a high number of frames, 256, 512 or 1024 ( preferably a power of 2).
It works great with color trails over a black background color.
I used the "Cube" Plugin but you can use any animation tool. (great results with particles, slow motion)
Frames MUST be fully opaque.
step 2 - Adding the frames together
(A)First, decrease the color brightness (to 10%), this will avoid color values to overflow.
(B)Split the layer in two, justify them to left, they should match exactly.
Merge the layers in add mode by dropping the upper layer's icon over the lower's one. Check the "Erase source" box.
Repeat the (B) operation until you have one frame left.
If the colors start to "burn", repeat the (A) operation.
step 2 alternative 1
Stretch the layer to 20% of its original size.
Normalize the color.
Repeat until there is only one frame left.
step 2 alternative 2
If your frames are 480/360 pixels or less :
Save your frames as BMP 24 bits.
Use FradderLight tool (free demo, PC) to add them together.
Choose the % value and then load the files.
step 2 alternative 3
Use Fradder tool from TPP (commercial tool set licence for 70 euros).
The addition is made using floating point values for better results.
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