BbB, it’s great to see that you went for 2.5D camera projection and matte painting technique because that’s where photo real animations are going to come from. ;-).
I have a few questions on the cityscape.
I ask this every time someone does Camera Projection with Blender, did you use the UVProject Modifer or ‘stickys’? hehe.
I think the idea of camera projection onto simple 3D is to give you some parallax with simple camera moves, panning and a little zooming in if you’ve done your mattes at 4K for say 1920x1080 HD you should have latitude to zoom in a little as well as pan. Your foreground objects would need to be simple 3D forms for the 2.5D but the further back buildings would suffice on planes with space in front and behind to achieve the parallax. Was that your approach?
Not sure how you went about it but in theory if you use a UV layer for each of your foreground buildings, where the camera move exposes unmapped areas of your model you need to ‘underpaint’ the texture maps, maybe Campbells Projection Painting build would make that easier where you paint extra texture cloned from your renders onto the UV layer onto the exposed areas of the model, running the camera move back and forth to check coverage until your happy with the extra painting.
Is your sky separate? Could you use an animated sky for more effect? Same for the water maybe just an animated spec map over what you have to give a bit of glisten?
Also the lens flare, as the camera moves that would move to I guess so again could you do an animated flare effect and comp it after?
Finally, the steam/smoke how about comping in some video practical effects from somewhere like http://www.detonationfilms.com/Stock_Directory.html they do quite a lot of free keyed footage of smoke / explosions etc. Slot them in on planes in the background gaps between the buildings maybe.
All adds to the believability.
Great to see you perhaps moving in the camera projection direction, especially with regard to your interiors, it would be great to see the same techniques used there with some green screen people moving within the interiors etc.
Have you checked out the podcasts on www.fxguide.com there are some great tips on technique and how they use camera projection for the movies. www.vfxtalk.com is another great site for help and tutorials, some real good stuff there. Maybe check out Dylan Cole, Chris Stoski and Nuke tutorials for more inspiration and techniques to transfer to blender.