1945–1958

His own recognizable individual style Sergei Osipov acquired gradually. Every year trips from the late 1940s to Staraya Ladoga, Izborsk, Pskov, and Staritsa helped the artist to restore his creative skills and establish himself in a circle of preferred topics. In the middle of 1950s in technical terms he was a well established as a master. This is evidenced his works partly shown at major exhibitions: A Boy^[10] (1950), "The Gathering"^[11] (1950), Pskov little street^[12] (1951), "On the Volga River"^[13] (1951), "Last Snow"^[14] (1954), "Reaping field"^[15] ( 1954), "On the Volkhov River" (1955), "A Little Brook"^[16] (1956) and others.

My creative life begins from the work under the landscape, – Osipov wrote in 1968. - The landscape has always interested and excited me as an artist. Working on him, I sought to express my feelings and love to nature of my native land.^[17]

About his painting style of this period can be judged by the painting Street. Pskov (1951). The artist himself considered it to be very characteristic of his early work, include this painting among only few works of the early 1950s in the exposition of the Moscow exhibition in 1983.^[18] It is distinguished by a certain conventionality of form, timid attempts to go away from the illusory naturalism to a more generalized manner of painting. In the future, Osipov will practically abandon the presence of figures of people in the landscapes and the detailed reproduction of panoramic architectural views.

The just following to nature no longer satisfied the artist. He felt the need to move on. But how, in what way? A new 1958 creative trip to Pskov and its environs gave Osipov, by his own words, some push.^[19] Landscapes painted as a result of this trip were positively received by critics.^[20][21]

1959–1969

A real turn in the artist's work was indicated in the works of the very end of the 1950s – beginning of the 1960s. Trusting to his own imagination, striving to achieve harmony and enhance expressiveness, Osipov is now less follow the path of nature, but to construct composition himself, inhabiting his paintings previously observed in life and nature. He boldly uses artistic generalization, sacrificing secondary details in order for more integrity of the image. One of the first works in which Osipov manages to most fully embody new ideas was the painting Little Houses at the Volga River^[22] (1959). To assess the turn in the artist's work, it is enough to compare this picture with the painting Street. Pskov (1951), which was mentioned above.

Among the works opening a new period in the artist's creativity were paintings Little Houses at the Volga River ^[23] (1959), "Outskirts of Village"^[24] (1960), On the Volkhov River (1960), "Still Life with Violin"^[25] (1960), "In the Old Ladoga"^[26] (1961), "Pskov", "Pskov Street"^[27] (1962), "Truvor fort", A Little Pskov courtyard (all 1962), "Fortress tower", "A Rick. Autumn", "Fortress in Old Izborsk"^[28] (all 1963), "Haymaking"^[29] (1964), and others.

The work of Osipov was inextricably linked with the theme of the Motherland – the Tver land, its nature, ancient Russian cities, and the peasant way of life. Since the end of the 1940s, he will annually, and often several times a year, travel to Staraya Ladoga, Izborsk, Staritsa, Torzhok, Pskov, bringing from these trips numerous studies, sketches and paintings. Then work continued in his city art studio. And so, year after year for forty years.

In according to opinion of Georgy F. Golenky, a Leningrad art critic and first researcher of creativity S. Osipov, new traveling enriched Osipov invaluable lessons of the ancient builders of temples and forts, whose hands, intuition, and artistic tastes had created a rare beauty. Only then did he realize that the ravines, hills, river beds, trees, houses must be depicted as structural elements of the environment as small elements of an overall coherent picture of the world, expressing its essential features. Only after this appeared in landscapes of Sergei Osipov soft Russian fruitiness, a clear rhythm, and unique proportionality, in which we accurately recognize the national character of the landscape.

By simplifying and light deformation of objects, Sergei Osipov emphasizes their three-dimensional structure, and internal force, the stress with which they have been created nature or man. "We must remind the viewer about the latent energy which filled every thing, - said the artist. - For me just here is a real hidden source of poetry, rather than in stories about the activities or events."^[30]

Indeed, in his canvases nothing "happens." But they come alive traditions, tastes, manners folk, they can feel our connection with life past generations. Another notable feature of his art becomes more abstract forms and the entire composition of the painting, a marked tendency to generalize, allegory, the desire to get away from naturalism to the contemplative and philosophical depth.

Other notable features of Osipov's painting become more conventional of the form and the whole composition of the picture at whole, a marked desire for generalizations, allegory, a desire to get away from contemplative naturalism to philosophical depth and some symbolism, but not crossing the line beyond which painting breaks with the real world. The style of the work of this period resembles a light “semi-cubism”, the form is formed by planes and faces. The most common color is lilac, in lilac tones Osipov writes the sky, water, a neutral background, the wall of the house, surprisingly subtly conveying the mood of the landscape.

1970–1985

The top of the Osipov's creation falls on the end of 1960s – early 1980s. At this time, he created a number of the best works, mainly in the genre of landscape, as well as a still life, which now occupies no less place in the artist's work. Among them Izborsk. Tower of XVII Century (1967), Crossing over river, In Suzdal, Izborsk Ancient Town (all 1968), "Still Life with a Balalaika",^[32] Silver villows, Wildflowers, Ravine. Grey Day (all 1970), "House with Arch",^[33] "Still Life with White Jug" (both 1972), "Autumn branch",^[34] "Staritsa town in winter",^[35] Landscape with Fortress, Winter in Staritsa (all 1974), "Cornflowers"^[36] (1976), "A Forest River" (1976), "Izborsk's slopes" (1978), "Small rick in rainy day" (1981), "Early green" (1982), "Dandelions" (1985),^[37] and others.

Traditional for Sergei Osipov theme of the spiritual sources, which has been sounded earlier in his still lifes, now was embodied with great power and artistic taste in Cornflowers (1976), Still Life with a White Pitcher (1972), Autumn Branch (1974), Dandelions (1985) and in some others works. Having escaped from some overload of details in composition, which was encountered in his earlier works, Osipov achieves in still life a great depth of image and associativity of hidden subtext.

The works of Sergei Osipov added to the Leningrad painting of 1970s their special contribution, original and significant.^[38] In his paintings much comes from the art of ancient Russian masters: laconicism of the artistic language, conventionality of form and accuracy of composition, resourcefulness in details, integrity, and expressiveness of the image built on unpretentious peasant material.

By opinion of Svetlana Makhlina, small landscapes of Sergei Osipov are endowed with extraordinary power of influence on the audience. And the point here is not only that the painter, using the image of nature in its many manifestations, creates landscapes that are consonant with the mental state of man. In all his works, the theme of the Motherland is revealed, sung by the artist with great filial love. And this is quite difficult, because raising a big topic and making it close and understandable in the landscape genre is very and very difficult.^[39]

Through all creativity of Osipov, the thought of continuity, of spiritual and cultural inheritance passes. In his works, the national past is not inseparable from the present. With his works, the author, as it were, confirms the idea that the beauty created by the ancestors does not lose its significance over time. She retains the ability to beneficially influence people and should be included in the spiritual life of contemporaries.

His style of this time similar of a light semi-Cubism. These paintings are nominated Osipov of the leading artists of the Leningrad school, who made his own contribution to its identity and significance.^[40]