Subaru + FOCAS observations of PNs in NGC 821

We present preliminary photometry of 122 PNs discovered in the elliptical galaxy NGC 821. We build the PN luminosity function (PNLF), which gives a distance modulus m - M = 31.9 $\pm$ 0.3, in good agreement, within the uncertainties, with the SBF distance modulus 31.91 $\pm$ 0.17 obtained by Tonry et al. (2001).