In the case of Kali and Durga idols, the use of chaalchitra serves several purposes. Firstly, it provides a visually striking and vibrant background against which the deity is showcased. These designs often depict mythological stories, celestial scenes, or intricate patterns that add to the overall grandeur of the idol. The backdrop is not merely decorative but is also considered a sacred space, amplifying the divine presence during worship.

The themes depicted in chaalchitra are deeply rooted in Hindu mythology. For Durga idols, scenes from the Devi Mahatmya or stories of the goddess's triumph over the demon Mahishasura are commonly portrayed. The intricate detailing in these designs reflects the artisan's mastery over their craft and their deep understanding of the religious narratives.

However, some historians have drawn our attention to the subtle ways in which temporal events were also figured into the imagery of chaalchitra design—from recognising specific patrons to celebrating familiar conquests over new territory or rival rulers. The shift in the popularity of motifs, from a predominantly animal-centric world to more anthropomorphic (albeit largely divine) icon-forms, also reflect a tendency to narrate human histories under terms of political and cultural patronage, according to historians like Sudhir Chakrabarti.

While remarking on the development of traditional puja imagery in Bengal, Sudhangshu K. Ray writes, ‘The first stage of the sculptural art of Puja is marked with god-heads. When developed further into the second stage, it began to record and illustrate important historical and political events that took place in the country from time to time. The main event we find, is depicted dramatically in three dimensionally modelled figures and (the) related story is drawn separately in a two-dimensional painting on the background called chalchitra, fixed invariably at the back and above the modelled images.’

The materials used in creating chaalchitra have evolved over time. Traditionally, artisans used natural pigments, such as turmeric, vermillion, and indigo, along with organic binders to paint the images on a backcloth of stretched, usually mud-caked, canvas or thick cloth. A ground would usually be prepared with mud and chalk before painting. However, with technological advancements, artists now also employ synthetic colours and materials to achieve more intricate and long-lasting designs. Sometimes, the images may be painted before on paper and then pasted on the frame.

There are usually three forms the chaalchitra can take, even though, as suggested earlier, the rounded, semi-circular arch is predominant. This is known as the ‘shaabek riti’ (the traditional method). The second form was popular at the Krishnanagar palace, which exceeded the breadth of the idols. The third type is made up of three vertices, used at the house festivals at the Pathuriaghata Tagore home or the Sabarna Roy Chowdhury estate.

In temple traditions of Kerala and Tamil Nadu, the prabhavali may remind one of the chaalchitra. It serves as a radiant and ornate architectural frame encircling the primary deity, often Kali or Durga, in temples and religious settings. This elaborate structure not only highlights the central deity but also symbolizes divine energy and spiritual power. The term ‘Prabhavali’ derives from Sanskrit, where ‘Prabha’ means radiance or aura, and ‘Vali’ refers to a boundary or enclosure. Together, the prabhavali signifies an ethereal halo or aureole, encapsulating the deity with divine brilliance.

Prabhavalis are crafted using various materials, including wood, metal, stone, and even precious metals like gold and silver, depending on the scale, budget, and artistic preferences of the artisans and patrons involved. Skilled craftsmen meticulously carve, cast, or sculpt these frames, infusing them with devotion, craftsmanship, and aesthetic beauty. Prabhavali designs include floral motifs and foliage, divine beings, celestial figures, mythological scenes and sacred geometries, including mandala-forms.