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I'm having a problem where the inside of a cup is way too dark. Even if I place a light exactly on top and really close the inside of the cups are too dark. Has anyone else experienced this? Is there anything to do about it?

Need to know material settings before proceeding any further...

It's a material I've used a lot for plastics. Obviously ceramic would be better, but I'm not sure how that differs to plastic parameter wise.

Materials specs:

BSDF 1 70%:

Reflectance 0: 240,240,240
Reflectance 90: 255,255,255
Transmittance: 0,0,0
Att. distance: 0.0
Nd: 1.000
K: 0.000
Abbe: 50
Roughness: 97

BSDF 2 30%:

Reflectance 0: 158,158,158
Reflectance 90: 255,255,255
Transmittance: 0,0,0
Att. distance: 100.0
Nd: 2.000
K: 0.000
Abbe: 50
Roughness: 8

I also did a new test render with a default plastic from the wizard. I still think it looks too black in side the cups, and the noise is really hard to get rid of:

eek, I had made a suggestion when looking at these images on my phone, but when I got home and saw them fullsize, I realized the fix I suggested wasn't going to do anything for you.

That second images is super super noisy for the SL and subject matter. What type of lighting setup are you using?

I'm just using a HDRI, no other lights.

Contrast pushes the darkest parts (of any image) toward black and the lightest parts toward white, which is why you are getting the result in the modified version -- there's no need to push the contrast as hard as you have.

Instead modify your lighting in Maxwell and you'll get much better results...

If you want to post the scene I can take a whack at it.

Best,
Jason.

Ok, now I have no HDRI either, just a sky dome. Left is my material specified above and the other a Wizard plastic (240,240,240). The obvious issues here are that my material are too dark and the other one is super noisy (and may also be too dark in the cavity). This is SL 16.30.

bLAZER76 wrote:It's a material I've used a lot for plastics. Obviously ceramic would be better, but I'm not sure how that differs to plastic parameter wise.

Materials specs:

BSDF 1 70%:

Reflectance 0: 240,240,240
Reflectance 90: 255,255,255
Transmittance: 0,0,0
Att. distance: 0.0
Nd: 1.000
K: 0.000
Abbe: 50
Roughness: 97

BSDF 2 30%:

Reflectance 0: 158,158,158
Reflectance 90: 255,255,255
Transmittance: 0,0,0
Att. distance: 100.0
Nd: 2.000
K: 0.000
Abbe: 50
Roughness: 8

Firstly, Abbe: Is this greyed out or do you actually have dispersion enabled? In a material like this it's unnecessary.
Secondly, Nd: I don't play with the wizards too much but is that really the values they gave you? An Nd of 1 means the plastic has the density of air, and 2 is too high. Plastic Nd's are usually in the 1.2-1.5 range.

do not use use anything with a "white' higher than 225,225,225 RGB or extra noise may result -- especially if the material is set to additive blending mode.

To be honest though it looks to me more like you either have the lighting too bright and/or the exposure too high.

Best,
Jason.

Are you sure that it is too dark?
Try to take a picture of a real mug in real condition...

Ciao, Gio

Here is a generic "white" ceramic MXM -- ideally ceramic would have some SSS properties but it would be so slight as to not be worth the extra render time.

Best,
Jason.

Here's a render with the generic white ceramic. I still think it looks way to dark in the cavity, if you compare to the following images:

The first photo has a strong down-light right into the inside of the cups -- you can see that clearly by the shadow underneath.

Set up similar lighting and see if you can compare apples to apples.

Best,
Jason.

Yeah, that's true. And it will probably look better if I also do that. But if you look and the second photo, that doesn't seem to be the case. I mean my first image is light up very much and almost black in the cavities, while this last photo has a pretty dim light and still looks brighter in the cavities.