Re: GAN?
GAN does use the real data - that's the whole point: "The system is fed an input of images and the generator tries to recreate the pictures, while the discriminator tries to distinguish if the computer-made images are real or generated." It is being used to clean up degraded images: "Pairs of galaxy images are used during training. One image is high quality, and the other is degraded by blurring the image and adding noise to it." As such, it is as valid as other techniques such as the "traditional deconvolution methods" mentioned in the article, and which it apparently outperforms..