ضوء الأمان المناسب لإظهار الأفلام البانكروماتيك .. كتاب أسس التصوير الضوئي

1) The appropriate safety light to show panchromatic films:

We previously knew that these films are sensitive to all visible rays, so it is difficult to choose a special safety light for them. However, it has been noted that the sensitivity of panchromatic films to the green radiation region is relatively low, so the appropriate safety light for that case is the very green color. Here, we mention that the sensitivity of the human eye to green rays is higher than the sensitivity of panchromatic films to those rays. Thus, the very small amount of green rays is sufficient for the eye to feel its effect, while that quantity is not sufficient to have a bad effect on panchromatic films.

In order for the photographer to always be on the side of safety, it is more appropriate to obtain the lamps that he uses from a store that sells photographic equipment and not from an electrical store that he is used to. The wisdom behind that is that the rays that come out from the light source may contain other unwanted rays of light, and the sensitive layer responds to them, thus As for those lamps that are sold in photographic shops, they are made after studying the spectral characteristics of the light emitted from them and the extent of its suitability for operations to show a specific film.