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Tom Wood
10-02-2008, 06:32 AM
I'm pretty sure my color sight is okay, but it seems to me that yellow renders as slightly green. I have to move over to light orange to get the darker shades of a yellow to stay out of green. Am I imagining things?

And for the cat people here, I almost made the title: Awl ma yellowz iz greenz!

3DGFXStudios
10-02-2008, 06:34 AM
maybe you ambient color is set to green?

Nemoid
10-02-2008, 10:13 AM
could be due to how shadows are treated by rendering engine ? however, I'd look to result if using a different light color works , go for it !

RollerJesus
10-02-2008, 10:43 AM
Is your light blue?

Nemoid
10-02-2008, 11:08 AM
remembered you also can use coloured shadows :)

Tom Wood
10-02-2008, 11:44 AM
Ambient isn't intentionally set to anything, but I'll double check. But even in Modeler in the surface editor, pick a yellow preset and look how the darker shades go to green. When rendered in Layout, even the lighter shades look greenish.

MooseDog
10-03-2008, 07:41 AM
what color is your parachute?

Nangleator
10-03-2008, 12:36 PM
I've always had people tell me my gold looks greenish. I'm color blindish, so I thought that was the problem...

toby
10-03-2008, 11:33 PM
Could be your monitor. Check out a monitor calibration website like this one
http://www.imaging-resource.com/ARTS/MONCAL/CALIBRATE.HTM

But I'll bet it's just the natural way we percieve colors. If you have no color in your lights and/or fill lighting, yellow will fall of to green in the same way that blue turns to violet when desaturated; (see attached) to me, this looks greenish at the terminator.

The trick is to not use perfect primary colors, they don't occur in nature, and they're less attractive anyway. In cases like the this where yellow falls off to black, you're basically mixing yellow with plain grey. Blue skies look wrong without some green, and yellows look 'unripe' unless there's more red than green in them.

gerry_g
10-04-2008, 10:06 AM
The image viewer lets you quick check any color in your render by just holding down the mouse on the desired area and reading the R G B values in the viewers title bar. R G B space is additive so Green will be

– R 0% G 100% B 0%

and Yellow will be

– R 100% G 100% B 0%


When I did a test and took a pure yellow and green patch out of Photoshop even with a pure white ambient value and a neutral grey BG color I still got around 10% or so noise from the other colors but if you're color blind a quick check like this should help give you confidence in you color management skills.

toby
10-04-2008, 11:51 AM
The image viewer lets you quick check any color in your render by just holding down the mouse on the desired area and reading the R G B values in the viewers title bar. R G B space is additive so Green will be

R 0% G 100% B 0%

and Yellow will be

R 100% G 100% B 0%


When I did a test and took a pure yellow and green patch out of Photoshop even with a pure white ambient value and a neutral grey BG color I still got around 10% or so noise from the other colors but if you're color blind a quick check like this should help give you confidence in you color management skills.
This is interesting, why do you think you're getting negative values? You've got more than just ambient light here, what are the sufaces like? You're using reflection and / or radiosity?

As far as noise, having Dithering on can cause that too. If you're going for pure colors that should be off.

gerry_g
10-04-2008, 02:01 PM
This is interesting, why do you think you're getting negative values? You've got more than just ambient light here, what are the surfaces like? You're using reflection and / or radiosity?

Well mostly due to the fact I'm dim, I loaded an existing file without checking all the the parameters, when I did check it over several of the lights were off white and one was pale blue, also the map had a gamma value of 120% (which is a typical set up for me but no good for a test). No dithering no radiosity (other than BG Radiosity) just reflections and shadows, even so when everything is corrected out there is still some stray color and I presume everything is adding up to more than a 100% because I don't have clamp values checked.

Nangleator
10-04-2008, 02:01 PM
I'm not terribly color blind, but I've gotten used to all the tools. My coworkers don't even know.

Thanks, Toby, I discovered a long time ago that very saturated colors don't feel very real in a texture. I hadn't realized that pure primary colors probably look even more fake.

Tom Wood
10-04-2008, 02:07 PM
I appreciate the discussion guys. A little over my head at the moment, but I'm looking into it.

toby
10-04-2008, 03:27 PM
Well mostly due to the fact I'm dim, I loaded an existing file without checking all the the parameters, when I did check it over several of the lights were off white and one was pale blue, also the map had a gamma value of 120% (which is a typical set up for me but no good for a test). No dithering no radiosity (other than BG Radiosity) just reflections and shadows, even so when everything is corrected out there is still some stray color and I presume everything is adding up to more than a 100% because I don't have clamp values checked.
I doubt that radiosity can ever give you results with no detectable noise, that's partially what makes it look good/more realistic actually. And using it with a grey background will introduce all the colors, that's where the blue values are coming from.

toby
10-04-2008, 04:13 PM
using it with a grey background will introduce all the colors, that's where the blue values are coming from.
Ok that was *wrong*, just as with a white light the green should filter out all the blue. It's because you're reflecting the grey, that would be additive color.