Diffuse Map Color Bleeding (or something)

jthacker

I've tried and tried to figure out why this is happening. I've searched all over the internet, and to tell the truth, I'm not even sure what to search for, so I figured I'd ask you guys!

Problem is this: I have a pretty intricate trim designed, but when it renders, the red from the swirlly embrodery has desaturated spots through it while in other spots, the red has bled through to the blue. I had this issue once before with another texture, and red and blue were the culpret colors then as well. I'm using the glossy plastic iray shader and the only change I made was adding the diffuse map just to test it. No special lights, default HDR settings. As far as I know, everything is at default. The garment was modeld in Marvelous Designer, if that helps, but I don't think that has anything to do with is since the last time I had this issue was with an item of clothing purchased from the Daz store, although it was a custom texture. Below is an image showing the original diffuse map and the way it appears once rendered.

Thank you for your help!

Richard Haseltine

What rsolution is the image (how many pixels on each side, not the PPI setting)? What happens if yoiu apply a simple chequer pattern to the item and render that?

jthacker

The resolution is 8000x8000. I scaled it down to 4000x4000, too, just to see what would happen. Same thing. I tired a checked pattern and it renered normally. 

Richard Haseltine

That's large enough to trigger iray's High Compression - in the Advanced tab of Render Settings. Try increasing the threshhold values there.

jthacker

That was it. I raised the threshold AND lowered the resolution of my texture. The only reason the texture is so big to begin with is that it covers an entire costume. Im just going to split each piece of clothing, which is what I should have done to begin with! Thank you so much Richard! I really appriciate your advice!