noob question

[den9]

how come for black and white film you having to do it in complete darkness? if that just to put the film in the tank?

what exactly is going on when you are working with the red safety lights? im completely new to this and dont understand.

do you use the red lights with black and white or just color? do you need to load the film on the reel in complete darkness with color film? :meh:

 

[ann]

film is very sensitive to light and must be handled in complete darkness when loading into a tank for development. After, it is light tight in the tank it can be developed in normal lighting conditions. Color film the same.

A "red light" is used in the darkroom when printing, it may also be amber. Papers are not sensitive to this light unless the light is very close to the paper, or your not using a "red light" that is meant for darkroom work.

Color printing is done in the dark at least for exposing the print, and then can be place in a special tank that is light tight and processed. If tray processing color prints that must be done in complete darkness as well.

 

[Dwig]

Modern B&W film, with the exception of a few scientific films, are sensitive to the same range of colors as the human eye. There is no light that you can see that the film can't. Hence, film must be handled in total darkness until it's processed.

Sensitivity to this full spectrum of light is essential. Otherwise the film would reproduce tones in ways that don't match your visual perception. You can see this in antique images made when common films and plates were blind to reds. Those films could be processed with a red light on, but by not seeing red they tended to reproduce blue skies much lighter, usually near white, than modern "panchromatic" films.

B&W printing paper, on the other hand, doesn't need to see all colors. The negative is already B&W. They are made so that they are blind to red/orange so that you can use a deep orange safelight.

Color papers are a different animal. They must see all colors, but are very much less sensitive to the orange color typical of the orange "mask" seen in modern color negatives. For a brief portion of time you can use a very, very dim orange filter. It is so dim that it takes awhile for you eyes to adapt and most workers simply work in total darkness instead.

 

[den9]

interesting! so i can put film on the spool in a changing bag, then once its in the tank and developed i can work in the light?

 

[ToddLange]

interesting! so i can put film on the spool in a changing bag, then once its in the tank and developed i can work in the light?

yup! once it has been completely been through the development process you can take it out into light.

 

[JC1220]

With the exception of developing film by inspection, where after 1/2 to 2/3 development is complete you may inspect the film by very low light, most often green, for a few seconds. A process primarily used for sheet film.

A green light is used not because the film is least sensative to it, but because it is one of the first colors the human eye can see and adjust too quickly.

 

[christopher walrath]

You can work in regular light (flourescent, incandescent, et al.). You run the fixer, generally, for twice the time it takes the film to clear. This means, twice the time it takes for the unexposed silver halides to be rinsed form the emulsion by the fixing agent. With most films, you can lift the reel from the tank after three minutes and inspect it. (First consult your film manufacturers product literature for specific recommendations.) If it is cleared then fix for another three minutes.

 

[Torus34]

You can get a pretty good idea of the whole B&W process in the series of 7 articles here on TPF.

If you have any questions, don't hesitate to PM me. I have a slight acquaintance with the author and am familiar with the articles.