The universality of the fundamental plane of E and S0 galaxies: Sample definition and I-band photometric data

As part of a project to compare the fundamental plane and Tully-Fisher dist ance scales, we present here I-band CCD photometry for 636 early-type galax ies in eight clusters and groups of galaxies. These are the A262, A1367, Co ma (A1656), A2634, Cancer and Pegasus Clusters, and the NGC 383 and NGC 507 Groups. Sample selection, cluster properties, and cluster membership assig nment criteria are discussed. We present photometric parameters that are us ed in the fundamental plane relation, the effective radius r(e), and the ef fective surface brightness mu(e), as derived from a r(1/4) fit to the obser ved radial photometric profile of each galaxy. A comparison with similar da ta found in the literature for the Coma Cluster shows that large systematic uncertainties can be introduced in the measurement of r(e) and mu(e) by th e particular method used to derive those parameters. However, the particula r combination of these two parameters that enters in the fundamental plane relation is a quantity that can be measured with high accuracy.