At our lab we use infrared inspection and it has saved many a clients work from under and/or over development. We picked up a pair of Russian surpplus about 8 years ago. We highly recommend the use of this method as even reading 35mm film is simple. The problem we had with using the green safelight (as most have) is that the amount of time you have to view the negative is quite short and takes ALOT of practice to be able to recognize just what you are looking at ( esp w/ roll film) With the infrared inspection you can be viewing the negatives from start to finish w/o any chance of fog. The goggles ran us around $600.00 US and uses two AAA batteries.