Hi Attila: Negative scratching from minilabs occur primarily in two places. The most common is in the film processor. Minilabs use what is called a leader card processor. The tongue of the film is cut off then the film is taped onto a plastic card especially designed for their model film processor. The film then follows an up and down path guided by racks through the various chemicals, then through a hot air dryer, then comes out the other end. Scratches occur if the film comes across something sharp, or if there is crystallized chemistry somewhere, or if the crossovers are dirty or don't move smoothly. The other common source is the negative carrier. If there is a piece of dirt on the drive roller or a little sharp edge or nick on the mask or film path, that can cause a scratch. It's very difficult to keep everything that clean and functioning, and most places have help that couldn't be bothered and management that pays lip service to quality control but provides neither the time nor the funds to maintain the equipment properly. The good news is that some of the digital minilabs now use ASF's digital ICE (Noritsu's in particular) to help minimize the problem. You might see if any of the labs are using a Noritsu minilab. Though, personally I don't always like their color renditions. My understanding is that rotary tube processing is the best way to process for absolute quality and a lack of scratches, but few places (and no minilabs) offer that service.
Butch
