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H$\alpha$ heliographs are imaging instruments designed to producemonochromatic images of the solar chromosphere at fast cadence (60 s or less).They are designed to monitor efficiently dynamic phenomena of solar activity,such as flares or material ejections. Meudon and Haute Provence observatoriesstarted systematic observations in the frame of the International GeophysicalYear (1957) with Lyot filters. This technology evolved several times until 1985with tunable filters allowing to observe alternatively the line wings and core(variable wavelength). More than 6 million images were produced during 50years, mostly on 35 mm films (catalogs are available on-line). We present inthis paper the optical characteristics and the capabilities of the successiveversions of the H$\alpha$ heliographs in operation between 1954 and 2004, anddescribe briefly the new heliograph (MeteoSpace) which will be commissioned in2023 at Calern observatory.

Optical characteristics and capabilities of the successive versions of Meudon and Haute Provence H$\alpha$ heliographs (1954-2004)