From my tests as shown in the screenshots below, the more realistic images generated by AI are all dependent on how detailed and clear the prompts supplied are, including the negative prompts [what to eliminate] as well as the AI program used - its models and the processing capability of your computer - especially your computer GPU.
The AI software l am currently using is Fooocus 2.5.5 in realistic mode. My primary workstation which houses an AMD Ryzen 9 3900X 12-Core processor, 64Gb RAM and an Nvidia RTX 3090 with 23Gb VRAM. The CPU usage doesn't top 12%, the RAM usage doesn't exceed 22Gb in my tests but the GPU usage tops around 91%
