The BioRad bulletin shows comparison of short time exposures to the film and imaging system XRS+, where the film shows limited dynamic range (http://www.bio-rad.com/webroot/web/pdf/lsr/literature/Bulletin_5809.pdf). However, it is noted, that the sensitivity is not as high due to limited integration time as compared to long exposure to the film. Does anyone have some idea about how long exposure to the X-ray film is suffficient to outperform the imaging system sensitivity and what is the detection limit difference between the two chemiluminiscence detection systems?