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                                                                                    Level 5

One hen, two ducks, three squawking geese, four limerick oysters, five corpulent porpoises...

 

Flashlight Powders

 

Chemicals Used In Black & White Photography

 

Chemical                              What It Does

K Bromide                                          restrainer

Benzotriazole                                      restrainer

Alum = K Aluminum Sulfate                hardening agent

Borax                                                 mild accelerator

Boric Acid                                          in some fixers

Glycin                                                slow acting developer

Halides                                               salts of fluorine, chlorine, bromine and iodine

Formalin                                             hardener

Chrome Alum                                     hardener

Hydrogen Peroxide                             a bleach

NA Metaborate                                  mild alkali

Metol                                                soft working developer same as Kodak's Elon

Monohydrated = containing 1 water molecule per molecule of the chemical substance

Phenidone = Ilford's developer - 1-phenyl-3-pyrazolidene

    A substitute for Metol by using 1/10th as much Phenidone

K Bromide                                        restrainer

K Ferricyanide                                  with hypo, it acts as a bleach, used to reduce density of the

                                                        photo image

NA Carbonate                                   energetic alkali, an accelerator in developers

NA Sulfite                                         Preservative and slow acting silver solvent

NA Tetraborate                                 Borax?

NA Hydroxide                                   very high Ph

 

Photography Calculations

P = pupillary dilation factor

C = circle of confusion

V = film format/image size

S = print size

D = film to subject distance, print viewing distance

dn = nearest point in focus

df = farthest point in focus

U = subject distance

F = focul length

f = F stop

H = hyperfocul distance

u = subject size

V = lens to film distance

M = magnification = v/u

t = depth of field

E = exposure compensation

1/V + 1/u = 1/F and M = v/u = V/U, u = V/M

V = uM

M = F/subject distance - F

V (Lens to film distance) = (M + 1)F

effective apperture = f(M + 1)

close-up exposure time = (M +1)^2 (time of distant exposure)

 

More to come, this is incomplete...

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