there is this art exhibit going on in london. (i'm countries away from there..) .. and it has everything to do with photo manipulation.  one of the is this one..and i'm getting way muddled up.. using bryce..where you can use a city.. create a water layer..and sink the city in it. how does one do this?? i seemed to have blanked out.. one of those 'dumb blonde'  moments,,  or s it painter? 

Looks like they just layered everything together. They took an image of the building from the same perspective and erased everything around it and placed it on the water.

Quote - Looks like they just layered everything together. They took an image of the building from the same perspective and erased everything around it and placed it on the water.

i dunno if they did it like that ..but its HOW i will do it

FlamingPear sells a filter called Flood which I used on a photo of my living room and herewith attach. There are many ways using the filter  to create the one you are asking about. Check them out and perhaps download a 30 day test drive. It is cool to use and I have not discovered all of the tricks with it.

 camera..thanks! your image is really good.. amazing. i'll download a free trial. 
bar-code, luke... that is an option.. but to do this here..it looks tedious..

Not that tedious, really. Create a layer, reduce the density of the water, enlarge the image and use an eraser to open the section that you want to appear out of the water. Flood does provide a lot of sliders and, I believe, a pdf for its use.

Oh my, it looks so real!! 

 yup lucie.. both images look real. there is some sort of exhibit going on in london..where there are pix of what london would look like years later with extreme climate change. out of the 5 or 6 images that the newspapers show.. 4 of them are photoshopped..

 

Camera,
I would like to thank you for the info too, because several months ago I was looking for achieving the same effect. Now I will check that FlamingPear plugin and eventually pick it up. Thanks again!

I do not think its the flood filter, it doesnt give you options that I know of to be able to do that unless they did each section 1 at a time with many layers.  Flood usually takes your entire picture, and creates the water plane from that, you can move the flood up or down but not around things.

but its very cool and well done.

Perhaps they flooded London for the day?

I'd say a lot of patience and clever use of selection paths. I say selection paths, because doing it all with the eraser brush by hand isn't very efficient and would be ridiculous. (When possible, work smarter not harder.) And don't forget there's always quickmask mode for those funny shaped spots. For buildings I'd either start with polygon lasso or pen followed by path to selection. Plugins may make it go easier/faster, but if you know enough of what you're doing you don't always need them.

Now the question is it done with masks, or are they erasing? (Not that there's much difference in the end result, but more a curiousity about workflow approach.)

After what Paul said.....it also looks like they added vertically flipped layer of the structures for a reflection value. blurred and low opacity amongst whatever other tweaking it needed. Also a shadow layer for the foreground buildings, which I would have used a gradient mask on that layer to difuse the hardness.

nice find...

i like the effects. ll surely try it..though it would be quite a catastrophe to see London is that situation.

thoughtiwasapussycat.. watch the movie.. flood. They used cg for it. but.yup.. london got flooded. http://www.google.co.in/images?q=flood+the+movie&um=1&ie=UTF-8&source=univ&ei=-FDnTJ3QOYKycLm0uJ0K&sa=X&oi=image_result_group&ct=title&resnum=5&ved=0CFQQsAQwBA&biw=1280&bih=685