Help, how did I get this backlight effect?

[dmerces]

SallyAnne, Dzenjo and Rich 2005, thanks to you three I’m finally able to reproduce my steps to obtain the effect I posted and I did no longer remember how I’ve got there. My method does not have the sophistication and technique of the methods all of you suggested. The steps I followed to obtain my effect were completely accidental. It was my birthday and I already had the "inspiration" coming from a few shots of Jack Daniel's.

Thanks your ideas I could reproduce my past steps and even improve the first version of my effect. Here are the steps I followed for the first version and for the improved version, so called because it implements a single color as backlight.

Thank you very much for your time and support and for so many inspirations and lessons with your techniques. Tonight I will sleep really relieved.

Original Effect Version
Steps
1. Set background color to white.
2. Remove Alpha Channel
3. Difference of Gaussians: Edge-detect> Difference of Gaussians | Radius 1=1,000; Radius 2=20,000
4. Color to Alpha: Color>Color to Alpha | Set target color to black.
5. Add any dark background layer and save the image.

Improved Version
Steps:
1. Open the image DM Logo Work.png
2. Set background color to white
3. Equalize: Color> Auto> Equalize
4. Mono Mixer: Color>Desaturate>Mono Mixer | Green =5,000
5. Difference of Gaussians: Edge-detect> Difference of Gaussians | Radius 1=1,000; Radius 2=20,000
6. Color to Alpha: Color>Color to Alpha | Set target color to black.
7. Add any dark background layer and save the image.