  We present a calculation of thermal photon production i.e. photons from
secondary interactions among particles produced in heavy ion collisions at
collider energies. This is done within the framework of hydrodynamics. We take
into account the lack of chemical equilibrium in QGP. It turns out that main
effects from chemical non-equilibrium composition of QGP, reduction of particle
number and increase in temperature, nearly cancel in photon spectrum.
