I don't have my own darkroom, so I send out to a lab to process my B&W film. They use Xtol straight in their dip and dunk machine. I've sent two films of Efke 100 to their lab over a 5 year period, and each time- it came back under developed. Now each film was used in a different camera, so I know the camera isn't the problem. That said- should I overexpose the film to ISO 80 or even 64 for next time? I'd rather do it in camera then request higher dev times, since they charge extra for specifying a time.