Hi @Miguel1900,
With 5.4 Development binary is mine is compiled as a optimized shipped with no debug, but more importantly my old GTX1050 took over 8 hours on 5.3 and 7.1 hours on 5.4, so your taking 3:45, an extra 60 seconds make me very envious😢
The reason for the longer time is the Lighting Quality HIGH and the changes to in BaseLigntmass.ini to HIGH. Because my graphics card is so slow I can see a very big difference in processing time from Preview also this might be the reason for the warmer picture, but GTX graphics card are know to be darker as they dont have hardware raytracing.
I have just tried using Lighting Quality set to Production and instead of increasing the total time the ETA is half the time of Lighting Quality set to High. Looking at the final picture there seems little difference