Tightness is is what is evaluated during Wrinkle rating. It is a measure of how tightly the seam has been compressed by the 2nd operation roll. It is recommended to evaluate the entire cover hook of the seam intact but in most cases, the rating is done after on a stripped cover hook after it has been cut at least once. The seam inspection software SEAMetal & SEAMscan typically allows you to enter or visually measure the wrinkle rating between 100% (perfect, no wrinkles) and 0% in increments of 10%. The measurements are saved once per seamer head.
An unacceptable tightness rating is typically below 70%.