Thanks for all the nice comments!
I had a lot of fun making this pic.
Wow that water and fog effect is just great . How did you do it , it looks really good ?
The pic is made up of several different images layered together. The water is an actual photo of a lake surface which I found whilst googling
(It's Lake Garda, not Loch Ness, but don't tell anyone 
). I liked the shape of the ripples and the colour and thought it might work well. The sky is just a gradient which I placed behind it. It always looks more realistic to use a blue which is darker at the top and fades down to white or very light blue at the horizon. I blurred the water's edge where it meets the sky to add a little more depth to the pic and hide the join.
Nessie and the figure riding on her back were photographed separately and then spliced together after the background behind them was cut away. I also cut away sections and then paste them back into the photo where stuff has to overlap, like one of the "plates" on Nessie's back which sits in front of his leg and her fin which goes over the waves.
The mist/fog was the easiest bit of all. It's just a special effect filter applied over the top of the image. You can download the program which Karim recommended here:
http://www.01net.com/telecharger/windows/Multimedia/photo_numerique/fiches/telecharger-21756.htmlThe instructions and commands are all in French - which makes it slightly more of a challenge - but it's a really good program for a freebie.
First select:
Fichier -> Ouvrir to browse and open the image you want to edit
Then to apply the fog, select:
Filtre -> Effet d'optique -> Brume -> Blanche (for white fog)
The black fog (Noir) would be really good for adding a smoky atmosphere to a photo, say for a burning building or forest.
