Hi. I’ve moved to Blender from C4D and am getting weird results from KB3D materials with a Fresnel node in them (not sure if this is due to KB3D or Blender). With C4D, the Fresnel effect is (and should be) a gradient which changes with the angle of incidence. But with kits like Minerva and Arch Vogue, the glass behaves improperly. The image shows how increasing the Fresnel value changes the reflection value as a solid edge across the glass rather than a gradient. Is Blender’s Fresnel just broken?
Try the “Layer Weight” node instead. (It’s under “Input”) It has two outputs for this kind of use. Also, always place a color ramp or map range node after to tweak.
Does that help ?
Also, is this full viewport shading or the “preview”(Workbench)?
That’s the view from the Shading tab set to Viewport Shading (GPU). It seems to me that the Fresnel node isn’t really doing a very good job if you have to add other nodes to make it work! I’m new to all this – do you have an image of a good Fresnel node setup to make it work properly, using Layer Weight and a ramp? Thanks!
I got it working in EEVEE with the “Facing” output of the layer weight instead of fresnel. Plugged it into the roughness of the glossy with a second ramp to make it glossier the steeper the angle towards the camera.
This sells most of the effect and is waaay cheaper, computation-wise.
I think the fresnel Node itself doesn’t work because it traces actual rays and therefore has to run in cycles but then again i don’t really know.
Sorry, I’m not working in EEVEE. I always use Cycles with GPU rendering (Viewport Shading button is misleading). The material setup is super basic, just the Fresnel node going into a Mix shader.
Great, thank you. In the mean time I used an architectural glass material from the Sanctus library, but I will need to go into those kits and alter the glass material to one that actually works!
Don’t expect everything in a “online asset library” to “just work” or even “be great or even decent”. So much I’ve checked out on BlenderKit has absolutely horrible materials - clearly there are no quality checks in place and anyone can upload whatever they see fit. Often with white meaning (1,1,1) way outside PBR cheat sheet albedo ranges.
I have no idea what “Sanctus library” even is, or what it’s so called “architectural glass” is supposed to mean. Normally for me, that means:
It’s based on transparency instead of refraction.
Fresnel is modified so that inverted normals still work or fresnel is replaced with layer weight completely.
Both options would look like this:
The preview shows what fresnel is doing without the inversion trick, whereas the rendered view has result hooked up to fresnel IOR.
Whereas for others, “architectural” means improving light transport through regular glass, which expect correct normals (no red faces if using the face orientation overlay) with geometry with thickness.
Don’t blame the creators for “creating something that don’t work”, blame yourself for not understanding what they have created and it’s intended use. I blame creators for messing up a lot of stuff and BlenderKit not having any quality checks. But hey, it’s free, and it’s good advice to be equipped to spot these shortcomings and fix stuff yourself. I’m not smacking down on BlenderKit here, it’s just an example; the stuff for sketchup warehouse is equally or even in worse shape. Same goes for expensive paid stuff - just because they’re paid doesn’t mean they get everything right or suitable for your use out of the box.
Don’t spend time complaining about the creators messing up. Spend it on improving your own skillset.
Woah, steady on. Nowhere in my original post am I slagging anyone off, so not sure why your tone is so aggressive.
For starters, I’m not talking about assets on Blenderkit, I’m talking about Kitbash3D kits, which are very expensive sets of building assets. Their materials (especially something like glass) should be better. And Sanctus is a high quailty paid-for set of materials on Blender Market. I just needed a glass that ‘worked’ – I probably shouldn’t have been so specific.
Yes I need to improve my skills with Blender, but the Fresnel node wasn’t working at all as I expected (compared to C4D). Clearly this app works in ways I’m unfamiliar with.
Fresnel node works exactly as intended with a few shortcomings not relevant here (no complex fresnel for conductive tint, no builtin glossy roughness accountability, have to account for “thin glass” ourselves). You didn’t show/share the full shader setup and the model it’s used on (thin vs solid) and the respective normals. The fact that I can no longer see straight through the glass as IOR increases suggests to me that the cupola is a solid glass object, or due to the sharp boundary appearing we’re seeing snell’s window due to normals pointing the wrong way. But without the actual project to look at, it’s very hard to guess what the problem is.
