I asked to Herr Claus Prochnow about this issue some months ago and he answered me that there are no practical differences between the Xenotar and Planar lenses used for the Rolleiflex cameras regarding quality. The tolerance Rollei factory required from Zeiss and Schneider were the same and Rollei tested the lenses in the same Zeiss K-6 tester machine, sometimes some lenses were closer to the tolerance limits than others, but it was applied for Schneider and Zeiss lenses, it means it could be very slight differences regarding individual lenses Xenotar and Planar; however most lenses Planar and Xenotar are made on the Rollei tolerance limits, Zeiss and Schneider used these tolerance limits all the time.- All the best Carlos _________________________________________________________ Horóscopos, Salud y belleza, Chistes, Consejos de amor: el contenido más divertido para tu celular está en Yahoo! Móvil. Obtenelo en http://movil.yahoo.com.ar --- Rollei List - Post to rollei_list@xxxxxxxxxxxxx - Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe' in the subject field OR by logging into www.freelists.org - Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with 'unsubscribe' in the subject field OR by logging into www.freelists.org - Online, searchable archives are available at //www.freelists.org/archives/rollei_list