can't find the mistake wich appears in render

[julie_elsen]

Hello,

I am a beginner in 3ds max. On my current project, I did something wrong but I can't find what. On the render I see something like a shadow, a cross, on both beds but it is supposed to be a flat surface. 

Can somebody explain me where the 'shadow' comes from? 

[CiroCardoso3v]

Add a smooth modifier.

[julie_elsen]

Sorry for the late answer.

Thank you for the respons. I will try that this afternoon.

But can you explain me how I got that "shadow"? It seems so strange to get that on a flat surface and I would like to understand what happens when I model.

[ads_czechoj]

Hi Julie, it is related to normals. I explained it in my attached video.

[julie_elsen]

Hi ads_czechoj,

Thank you very much! I don't yet understand it entirely but at least a lot better than before.

Can I ask you another question?

I try to work with loft so I got a path and a shape. The path is a vertical line made in front view. When I first select the path, than create loft and than select the shape: the loft looks okay, in the right direction, vertically.

But when I first create loft, than select the path and than the shape: the loft goes in the different direction, it suddenly lies horizontally. 

How does this works? 

[ads_czechoj · Accepted solution]

Like almost tools in 3D software, the Loft in 3ds max has built-in some logic. We can ignore it and assign the path to the path or shape to a shape. The results might be predictable or unpredictable. 
If you selected the vertical line before selecting the Loft Compound object and then selected the same line as a path, you added the path to the shape. Shor to say:

1. We must select any spline object to activate the Loft Compound object. 

2. Once the spline is selected and the Loft activated, the UI appears in the Command Panel. 

3. Now, the user must decide whether the previously selected spline is a shape or path. The following selection will create a path or shape for the Loft based on the answer. 

The "error" of the Loft direction you see in your example is related to the fact that you applied the same line as a shape to the already-picked path. This changed the direction of the loft after adding another spline as a second shape. This overwrote the previous shape (a line).
I would suggest reading documents and watching a few video tutorials for more details. One of them I found handy:
Help: https://help.autodesk.com/view/3DSMAX/2023/ENU/?guid=GUID-4CCA4890-83E8-41C6-9FFB-0A3959194CCA
Videos: 
https://www.youtube.com/watch?v=vbwlg_IfuSc

[julie_elsen · Accepted solution]

thank you very much! This was all very helpfull 😉

[ads_czechoj]

You're welcome, Julie.