Post production one of buildings in after effects. My post work most of the time is made out of layers that I then use to bild up my final beauty pass. I prefer to do it this way because it give me a lot more control over my final result and let me achiev effects that I could not achieve using just a beauty render.

So lets get it started. As first layer I pick up GI- I use this layer because it let me see all that is in a scene and control overall tint of objects. It is worth to notice that I cant completly change colors of buildings because their bounce reflection would be different from new one. In that case it is crucial to be as accurate as possible in render application or do only small changes in post to collors.

 This is a pure GI, it looks quite ok not much to change except for the hue of the lion heads

 And here is GI with lion heads hue changed

 Darken down the floor and hue correction

 Here you can see GI + Light pass

 GI + Light + Reflection pass now its worth noticing that each light, reflection, refraction etc passes are being retouch and tune up to my neews

Some more retouching diffferent areas, window, cement, metal and so on. Tiny changes nothing too big.

 And here we have final image, below you can see breakdown of AO pass and light pass

Since I am a big fan of keeping all as physically accurate as I can I blended my AO with Light pass. I did it because in reality when we look at direct light there is no shadows where light hit, however the extra AO pass apears everywhere else where light pass dont hit. There fore I ADD my light pass on top of AO and decreased it to 25%. Thanks to that AO sems to disapear in direct light areas but it still remains in shadow giving me an extra details.

I have also used AO pass in some cases to add extra dirt and discolorations, using different noise maps to colorise AO pass and then use it as color mask for final image I was able to add extra level of dirt and discolorations.

Here you can see my light pass. I was unhappy with a lot on this image there fore I started on tweaking hue and brightness of my objects untill I was happy with it.

The image above is getting an extra relight from my post work. I have used normal pass in world coordinates to produce a RGB based image. I then used it to add an extra layer of light on my building to boost up the sunlight. I used this technique in many situations such as adding extra light to glass. It is not really physically accurate, but because the glass is 100% transparent and clean in CGI it does not catch any light, where as in reality it would be dirty and grey which would make it catch a layer of light.

Above you can see my final light pass, I believei s roughtly where I wanted it to be, the only mistake I did was to put the two mid ection blocks too bright making it a bit too unrealistic - will need to fix it.