Halftone pattern and artifacts around edges of objects in the generated images
Hi,
I'm getting visible halftone patterns in my generated images. I can also see some artifacts similar to jpeg compression around the edges of objects (for example, around the backpack and around the woman's face from the examples below). I've attached a couple of examples - blown up cropped images and the full images they were cropped from.
I tried with many different sampler/scheduler combinations, and increasing the number of step up to 50, and I still get this visible pattern and artifacts. Can I make them go away or is it inherent to the model? I use ComfyUI updated to the latest version and the FP8 version of Qwen Image. My GPU is RTX 5090 and I have 96GB of system RAM.
those white dots I see them too, I changed the AVE to wan2.1 vae and uniPC, Normal, seems to produce better quality in low cfg (2.5) and steps (20),
I get the same thing. It looks like the image is being seen through a screen door. No setting adjustment seems to fix it. Changing the VAE, samplers, etc. does nothing. Upscaling the image only makes it worse. Qwen is unusable because of this. Very disappointed..
I also noticed that the quality of some images is not very high. In some cases, upon close inspection, there are artifacts, a sense of JPG image compression, vertical stripes, and the text content has a photoshopped texture. The texture of the text rendered in the image doesn't blend well with the picture. I also wonder when the Qwen team will address these model issues in the next update. I hope the image quality problem can be gradually improved. Besides that, the model performs outstandingly in other aspects, and the flaws do not overshadow its virtues.
I got it when trying to use the lightning lora most often. Then I realized the lightning lora wasn't even being applied (look for errors in console if you're trying to use it). Once I fixed that (switched comfy to nightly build instead of stable and updated), perfectly clear images.
I did see it some with 20-30 step renders without lightning (not really at higher steps than that). I think I played with the sigma shift and managed to get some of it to go away.
those white dots I see them too, I changed the AVE to wan2.1 vae and uniPC, Normal, seems to produce better quality in low cfg (2.5) and steps (20),
I've just tried this and it made the halftone pattern even more noticeable. :( I think it might be a problem with the VAE. I wonder if an FP32 version of it will fix this? In any case, hopefully they will have a look at it and address the issue since the model is otherwise very good.