uvby-Hbeta CCD Photometry of NGC 1817 and NGC 1807
  We have investigated the area of two NGC entries, NGC 1817 and NGC 1807, with deep CCD photometry in the uvby-Hbeta intermediate-band system. The photometric analysis of a selected sample of stars of the open cluster NGC 1817 yields a reddening value of E(b-y)= 0.19$\pm$0.05, a distance modulus of V0-MV= 10.9$\pm$0.6, a metallicity of [Fe/H]= -0.34$\pm$0.26 and an age of log t = 9.05$\pm$0.05. Our measurements allow us to confirm that NGC 1807 is not a physical cluster. 
L. Balaguer-Nunez, C. Jordi, D. Galadi-Enriquez, E. Masana