Dear PAs: Light Grey is Not White...
Nyghtfall3D
Posts: 813
... and I'm tired of correcting your Iray shaders.
Regards,
Nyghtfall
Post edited by Nyghtfall3D on
Daz 3D is part of 
Connect
DAZ Productions, Inc.
7533 S Center View Ct #4664
West Jordan, UT 84084
Licensing Agreement | Terms of Service | Privacy Policy | EULA
© 2026 Daz Productions Inc. All Rights Reserved.
Comments
Dear Nyghtfall,
MANY light sets tend to blow out "pure white" - adding a light grey helps to keep that from happening.
And since you're the first person I've seen have an issue with the light grey that some PAs add to keep the blow-out from happening (but I've seen more people have an issue with the blow-out from "pure white" when it isn't added) I'd say it's probably a good thing that PAs do add it. Also - pure white is very very rarely seen in the real world. Look at photos of people wearing white and it's almost never pure white.
Regards,
Diva
Nvidia tends to recommend this for Iray shaders, like mentioned here in this manual.
http://www.irayrender.com/fileadmin/filemount/editor/PDF/Preparing_Content_iray_24.pdf
Ah. Then I stand corrected. Thank you for enlightening me.
Sincerely,
Nyghtfall
...Ntghtfall is not the only one. One of my characters is albino, a couple others are fey with stark white hair.
Albino hair completely lacks any melanin (the basis of hair pigmentation) so it is actually a pure translucent white It took me weeks to work this out out with the help of others, even using dedicated hair colour resource tools. Usually the best I could get was either a very light grey or light blonde even with changing the the light to a higher temperature than 6500°K (which unbalances lighting for the rest of the scene) or altering the tone mapping (which also affects the entire scene as well).
Albino hair may pick up a slight refractive tint from the surroundings and lighting but still for the most part is still totally white and colourless.
Actually, albino hair is oh-so-very-slightly yellow due to keratin. It's why old ladies use blue or purple shampoo or blue or purple rinses because it cuts the yellow color in their hair (like bluing does with whites in your laundry).
Laurie
What parts of the shader are you trying to turn white if you have need of that in your particular case? I believe you should be able to set up a shader that will make that change and you could then do a shortcut for a button on the UI to change when needed.
Dear God. Someone just apologised politely on the Internet. Swoons.
...this is what I was finally able to get after weeks and weeks of trial and error. I spend a lot of time also studying albino hair as well as skin using photo references.
This +1
A good friend of mine is albino, his hair is yellowish, I have known him since high school his hair has always had a yellow cast. I have also photographed albinos when I was a photographer for their senior photos, all have a yellow cast to their hair. Some use a bluing agent to make it more white and counteract the yellow, some don't. Also their hair picks up impurities easy, like if they have rust in their water it becomes even more yellow.
One thing that I like to have pure white for is Drow elves, they have either white or silver hair and have no yellow in their hair, it is pure snow white if it is white. Sure that is not something natural, but when rendering fantasy creatures you render non-natural things so...
As mentioned above by AllenArt a blue rinse makes white look whiter, just a tiny tad of blue, a miniscule amount.
Rendering is not a real world medium, artisitc liscence has to be taken in many ways in order to make products that render well.
PA's always try to do their best to make stuff that will render nicely and give good results over a broad spectrum of use. That is our job.
If things dont suit your personal idea of how things "should" look and you can tweak it, then there really is no problem. We cannot take into accounts everyones personal opinions on how things should look.
I have several characters in my books with white hair. I ended up using a very pale gray. White does get blown out very easily. And if there are any colored lights in the scene, the hair picks those up too.
I don't have any benchmark tests to definitively prove this, but using not quite pure white, and not quite pure black seems to render a bit faster, which is something that I thought other people enjoyed.
Good tip! And what folks are saying is true. As a hairdresser I can attest that unless your snow or something so stark there is going to be a bit of color whether it's got a little blue or yellow or red in it, might look pure white to the naked eye but in reality there is SOME pigment there, trust me on that! lol
The colour we see is reflected light and is based on the absorption of the reflective surface. Snow looks white because it reflects all the colour spectrum but not equally. As it is water based it absorbs the reds first so snow, and ice, can look blue at times. All coloured substances are the same and what we see is the spectrum that is left after the light is absorbed by the surface hence nothing is pure white. In photography I use 250, 0.96:0.96:0.96 in Studio, and tend to use that in all the whites used in shaders that don't have a diffuse map. I have also used 217, 0.70:0.70:0.70, but not all renders and light react nicely with that setting.
This may be of interest.
https://www.the-cryosphere.net/10/2541/2016/tc-10-2541-2016.pdf
In this one I set SSS to take out some of the red and set the Refractive Index to 1.30, ice, which made the layers look blue.
1.0 is not the limit in nature. I've seen OBA papers up at 1.07 diffuse reflection, and I assume a sufficiently OBA white cloth could hit similar levels. OBAs (optical brightening agents) work by absorbing UV and reemitting visible light (most typically blue, becasue that both adds brightness and counters the tendency of paper, cloth, white hair, etc. to look yellow, but OBAs can be formulated for any color (white LEDs work by using the same chemistry as OBAs).
One never wants to put pure "computer" wite in a shader or in a texture when trying to simulate reality. Nothing in non computer reality is pure white. It is in a range of very light grays. When you see 'white' as a name, think realisim - there is no such thing as white, but a lot of subtle light grays.
For example IRL, of you have a whote shirt, and you shine a white light on it, it gets lighter. If one puts pure white in a shader, and the end user shines a light on it, ou are more likely to get a cartoon effect than realism. Putting light gray in place of white in various shader settings is not an error, it usually means the vendor is more educated about how light and color works.
For further reading, people are welcome to google 'values' in art.
Here is an example: https://thevirtualinstructor.com/Value.html
...some of the photo references:I used:
You'll notice how her blouse looks whiter than any part of her.
And that these are "glamour" shots-- filtered and color balanced most likely. The middle one isn't even albino. It's makeup and a wig.
I’ve met a few albinos and there is no specific colororation. They all seem different to me.
I had a neighbor who was African American albino and her hair was blonde and her skin pink colored and freckled. In high school I knew two twins who were albino both were platinum blonde with pale blue eyes and pink skin.
I grew up in NE Illinois where we had lots of snow for months in the winter, and although it was white, it did have a very slight bluish cast to it. Sure, it can be blinding white that makes you see spots like a camera flash would, but there is that very slight bluish cast depending on where the sun is and time of day.
Exactly. There are 3 different coloration chemicals in our bodies, and melanin is just the one everyone talks about (and generally the most prevalent). Keratin (the one that causes the yellow/orange cast and makes redheads) is still there as is the other.
Well with snow it's the reflection/refraction of the light hitting and the particles reflecting what's around them. It is after all just frozen water but yea, depending on where it falls it's going to look like it's got a slight cast of color to it... unless someone pees in it.... then there is yellow!
Hilarious Tim!