Bob:(posted 8341 days ago)The films available today from SFW are C41 compatible. Those who say otherwise are not up to date with their information. However, some of the older movie stock films are still floating around out there. The way to tell the difference is that the base side of the movie stock films are black. I worked for a number of years in a local lab that readily accepted SFW films if the film base was not black. At that time the bar code on the films made them print using the printer's Scotch film channel.