THE CONSISTENCY OF STROMGREN-BETA PHOTOMETRY FOR NORTHERN GALACTIC CLUSTERS .3. M67

We have measured M67 stars in a Stromgren-beta system based ultimately on data for the Hyades and Coma clusters. By comparing our results to previously published data, we have derived formal corrections require d to put the other data on our system. Corrections which are Statistic ally significant by our criteria are found for Stromgren measurements made by Strom et al. (1971, PASP, 83, 768). Those corrections range be tween 36 and 61 mmag. In addition, corrections of 17 and 8 mmag, respe ctively,are found for beta measurements made by Eggen (1981, ApJ, 247, 503) and Nissen et al. (1987, AJ, 93, 634). In addition to considerin g M67, we have updated earlier work of ours which was done on Praesepe and NGC 752. After revising our criterion for statistical significanc e, we have changed our judgment about two corrections which we had der ived for published data for those clusters. Further work will be requi red to verify the reality of those corrections. We have also compared our results to closely similar work which was done by Nissen (1988, A& A, 199, 146) and which had previously escaped our notice. Differences between our results and those of Nissen appear Is exist for beta in Pr aesepe and for c(1) in NGC 752. Independent measurements support our P raesepe result. but the problem for NGC 752 remains unresolved.