This question is too professional. For ordinary people, even art lovers, fakes, or imitations can't be distinguished by the naked eye. (long text and many pictures)
The fundamental difference between the two is very simple, the uniqueness of the original author's attribution.
General imitation is divided into several situations.
In ancient China, the ability to copy prints was limited, and it was impossible to show the changes of the original pen and ink, so there were few opportunities to see the original. Copying has become the only way to learn ancient paintings. Therefore, the original purpose of ancient copying painting was to learn, and sometimes even the words came down together. But some people, vain (pretending to be forced), want to decorate the facade and improve their status, saying that what is good is genuine, and some collectors have poor eyesight and tell the truth. So they wrote words on their labels, borders or paper tails, saying that it was true, and they also wrote them in their calligraphy and painting works. On the other hand, it is also very special to return the fake ones and accept the original ones, such as Mimi. Su Shi's poem "Stealing the Ancient, Who Laughs Like a Stupid Tiger's Head" is about Mi Fei.
Driven by commercial interests, China's paintings and calligraphy not only have their own artistic value, historical and cultural value, but also have value-added economic value since ancient times. Under the temptation of profiteering, imitation appeared. Some copy directly, some copy by rubbing, some copy intentionally (that is, copy the artist's creative state at that time), and make something out of nothing (discover the artist's works out of thin air) all for money. Now, even if this painting is famous, there are different opinions. Ultimately, it is necessary to reach an agreement or a majority. What the predecessors have evaluated needs to be sorted out again to see the basis of his evaluation. If it is not credible or flawed, the work becomes a test.
There are only two appraisal methods: style and art history appraisal and science and technology appraisal.
For artists, style is the core symbol of their identity. Art history is the history of style, and the change of style has its deep-seated reasons, and the external performance is the work. Personal style, genre style, era style, the time axis of the artist's style, his composition, taste, talent, cultivation, thoughts, concepts, emotions, persistence, temperament and aesthetics are all expressed through his works. The appraisal of style may be emotional, because this feeling is unspeakable and can only be understood. I think this painting is real. Others have other people's logic. If opinions differ, they are almost irreconcilable. In Chinese painting, meticulous brushwork, big freehand brushwork, small freehand brushwork and double brushwork, except meticulous brushwork can be accurately restored visually, there are too many accidents in other brushwork, it is impossible to be exactly the same, and the style is too conceptual. The only irrefutable evidence is the mother side, and the mother side has the mother side. Pull it out and you will know. If there is something in the painting that obviously doesn't conform to the historical facts, it must be a fake, because the flaws are too obvious and other consistent styles are completely unconvincing.
Looking at the style, telling the truth is the most direct, and if it is not in line with historical facts, it is more convincing.
For example, in terms of materials, the use of materials and the identification of details and characteristics.
For example, it is a unique phenomenon in the late Ming and early Qing dynasties to take pictures with silk. Some painters personally have the habit of using paper silk. For example, Zhang Lu, a painter of Zhejiang School, often uses a kind of thick silk, which is as sparse as yarn. Dong Qichang, a painter and painter in the late Ming Dynasty, used a kind of Korean paper for many times, which was smooth and dense, and was a tribute from Li Pan in The King of Korea in the second year of Wanli (1574). Painters Liu Yong and Liang in Qing Dynasty like to use crayons.
But materials such as paper and silk can be forged later, so they are not unique. There are also some details of artists' habits.
During the Song and Yuan Dynasties, the phenomenon of having no money, being poor and hiding money often appeared, which may be related to their calligraphy level, but it was more determined by their thoughts at that time. For example, Ni Zan, a painter in the Yuan Dynasty, used no seals for his paintings and calligraphy. However, this is not absolute. Can't say that Ni Zan's money is fake. In fact, Ni Yunlin's original "Qiu Linye Xing Tu" (collected by the Metropolitan Museum of Art) stamped the "Yunlin" chapter after the money;