Previously, Autobild gave fairly clear renderings, but since w213 something went wrong, probably lost the insider...
Simple, since no more Huckfeldt renders, Autobild has been all over the place with its renders. Huckfeldt's renders were some of the best in the industry, realistic and close to production. Not always 100% and sometimes only 50% but he improved on his renders as time passed and was usually close.
Larson has usually wild ideas and designs in his renders, more angular and radical than what the cars would look like.
Reichel is well, Reichel, he can create some good renders but they are usually nothing exciting. He has improved but he is no huckfeldt.
Then there's Avarvarii, he has the skill and can create some pretty decent and realistic renders. But I don't think he always has access to photos from design clinics or inside design studies since a lot of his renders are not even close to the final design. There are instances when he is very close, usually a concept turned into a production car but usually the small details that make the real car are lost in translation.
Finally there is Automedia, they provide spy photos and renders but I have no idea who does their renders, maybe it is one person or perhaps a couple, but their renders lack cohesion and they all feel different. Some are good but most are mediocre and lack any polish.
There is also Julien Jodry, he works for auto moto and his stuff is pretty good but he seems to focus more on french brands since auto moto is a french magazine, but his non french car renders are pretty good and quite nice.
There are some other people for sure like radovan varicak and his stuff does appear on autobild, but his renders are way out there in terms of design. I'm sure I am missing some. thanks for reading.
edit, forgot x-tomi. Fan of his work, Rarely creates new models or does major renders, usually quick edits, like amg version or M versions of base models. Sometimes does cabrios, coupes and wagons. Usually creates pretty realistic renders, which is always nice to see.