An image forming apparatus includes an exposure portion having a light source,
for forming a latent image on a photothermographic imaging material by exposing
a light beam, a thermal development portion having a heating portion for thermally
developing by heating the photothermographic imaging material on which the latent
image is formed, and a cooling and conveying portion for conveying and cooling
the thermally developed photothermographic imaging material, a temperature detecting
member for detecting at least one of a temperature of a predetermined portion concerning
the cooling and conveying portion, and a temperature in a vicinity of the exposure
portion, and a control unit for controlling a factor relating to thermal development
on a basis of the temperature detected by the temperature detecting member.
