All materials with Principled Shader are rendered wrong in Blender 4.1.1 in Cycles. if it has a low Alpha number. If the attached file is opened with Blender 3.67 the render is good but If the same file is opened with Blender 4.0 or 4.1.1 the render is wrong.
Please find attached a demo file to show the problem. In renders the problems seems quite problematics but when the scene is complex (ej. buildings) the result it’s even worse
It is known to produce different visual results. From what I have seen so far, in most cases it is relatively easy to achieve results that look more similar to the old Principled BSDF.
If you have a specific problem, I wouldn’t be surprised if you could find the answer in this thread:
Thank you for the fast answer. I could realise that If I adjust specular IOR or Transmission I can achieve the same results as before but with the problem that I have to adjust the environment light.
It’s quite problematic because I’ll have to change all materials to adjust to new environment light.
Even though I think that the results with the IOR=0 or Transmission=0 are not correct because the result it’s like It was dirty, I can’t find the sense
The file that I uploaded was not correct, I can’t upload the files with the problem because they weight to much.
I contacted with Blender and it seems that is an issue that they implemented to save memory but in several cases have some problems. Now to avoid this problem, I have to increase the bounces, spending more time in render time but it solve the problem
