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Rotation issue
🕑 Added 2024-09-05 12:13:49 +0000 UTCI want to tell you about another SD limitation that you constantly have to bypass for the best result - Faces at an angle. Yes, you read everything correctly, SD does not know how to generate faces from a strong angle, it knows how to make a full face, a face from the side and from behind, but a face, for example, looking out of a corner, never, only with the help of all sorts of LoRA.
Let me prove this to you with the simplest example, we will watch how SD will change Amy's face to Sarah's face at several degrees.
First, we will not rotate Amy's face and just change the face to understand what SD can do in ideal conditions when the face is clearly visible and not rotated.
SD did everything great, I don't see any problems or artifacts. Very good and round pupils, even with glare.
We turn the original Amy by 15 degrees.
We change the face and twist what turned out to be back so that it is easier to compare with 0 degrees. Next, I will skip these steps and immediately show the result so as not to waste your time.
We see that the left pupil has become shapeless. Yes, even at 15 degrees there are already such strong differences that make art worse, but we have just started.
After 30 degrees, I must admit that the shape of the face is still very good, eyebrows, mouth, everything looks good except the eyes... For some reason, they have changed color and shape, and now they are looking away, not at the camera. And they're not Sarah at all...
Okay, then 45 degrees. Now everything except the eyebrows. The jaw is deformed, the nose is broken, the mouth is not symmetrical, and everything is very bad with the eyes. In general, everything is very, very bad and it is already more frightening than attractive.
90 degrees. Surprisingly, the shape of the face is better than at 45 degrees, but everything else... That's why you can't find art with turned faces, originally only generated.
For the sake of a joke, here are 180 degrees and I won't turn the result back. As you can see, SD did not even realize that the image was upside down and began to redraw the face at 0 degree, despite the context.
Yes, it's all very sad, but how do you still get around this limitation of SD 1.5? It can be tricky. The idea is very simple, if the face in the original image is rotated by more than 10 degrees, then first you have to align the face, rotate the original until the face is at 0 degrees and generate only it, then rotate it back and generate everything else.
By the way, this is what happens if you try to generate the original immediately.
Let's change this image. In the original, the face is rotated as much as 41 degrees, which is very unsuitable for SD.
Therefore, we rotate the original by 41 degrees and generate a face.
Next, we rotate what we got and generate everything else (except the hands - it's still kryptonite for SD).
Boom, we get a great result with playful Amy.
