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Forensic Photography
Chapter 5
Photographic Printing and
Chemical Processing
A. CHEMICAL PROCESSING
After the exposure of the film to light in the picture taking, the
next step would generally be chemical processing.
Black and White Processing- development, stop-bath, and
fixation.
Color Processing- development, stop-fix, and stabilizer.
1. Development- is the process by which an invisible latent
image in an emulsion is made visible.
B & W Emulsion- the image is composed of grains of black
metallic silver.
Color Emulsion- the developed silver is replaced with cyan,
yellow, and magenta dye.
2. Stop-bath - halts the developer action in appropriate moment.
It also prevents the contamination of the developer and fixer
from each other.
3. fixation- makes the developed image permanent when it is
followed by a thorough washing. In this processing stage, the
unexposed undeveloped silver halides crystals are dissolved
and removed from the emulsion of the photographic material.
B. FILM PROCESSING
It can be carried out in trays, tanks, or mechanized
equipment.
Panchromatic materials- handled in total darkness.
Blue films, orthochromatic films and printing papers-handled
under a safelight.
1.Equipment for film processing
a.Tank or tray
b.Developing reel
c.Opener for film cartridge (pliers)
d.Scissors to cut the tongue of the film
e.Thermometer
f. Timer
g. Funnel
h. Photographic sponge
i. Films clips for drying
j. Glass or plastic bottles for
storing mixed solution.
Tank Tray Developing reel
Opener/ pliers Photographic sponge
 Small format films like .35 mm is best developed in a
cylindrical daylight developing tank that accommodates a
spiral reel.
Metal reels- have a center lip or hook to hold one end of the
film, the remaining length slips into the grooves created by the
spiral.
Plastic reel- is loaded by simply pushing the film into the spiral
from the outer end.
C. FILM PROCESSING PROCEDURE
1. Tank method of the film development
a.Mix the developer, stop-bath, and the fixer according to
instructional manuals. Then bring it to temperature which is
20-21 C or 68-70 F.
b.In a dry area, lay out the film, opener, scissors, reel and
the tank so they can be readily located in the dark.
c.In complete darkness, open the film cartridge by simply
prying off the cap opposite the end, where the long spool
core protrudes.
Reeling Procedure
To load a metal spiral reel, hold the film with the emulsion side in
or down loosely in one hand while the other hands holds the
reel. Slightly squeeze the film width by pressing between the
thumb and forefinger so it narrows just enough to fit into the reel.
It is advised for beginners to practice with unwanted film several
times, first with the light on. Once you get the feel of it, start the
practice with eyes closed to simulate darkness until the exercise
is perfected.
d. After the reeling of the film is done place it inside the daylight
developing tank then cover it. White light can now be opened.
Remove the lid cover of the tank is full. After 5-6 minutes pour
out the developer.
e. Pour in the top-bath, agitate the tank some more and after 15-
20 seconds drain out stop-bath. Next is to pour in the fixing
bath, after 15-20 minutes drain the fixer from the tank.
f. You now wash the negative for several changes.
g. Remove the negative from the developing reel. Water that
adheres on the surface of the negative cause watermarks if
allowed to dry without wiping.
h. Hang the negative to dry at a clean, dust free place or better in
a negative drier.
Tank method of film Development
2.Tray method of film development
With this method of film development, the developer is placed on a
tray. In total darkness, remove the film from the cartridge then hold
one end of the film is thoroughly dipped until the whole length of the
film is evenly wet. Timer will start now. With see-saw or pulling up or
down motion, move the film from one end to the other then back,
continuously, until the developing time of 4-5 minutes is done. Then
transfer it to the stopbath for 10-15 seconds with the same motion.
Thereafter, place the film in the fixer and execute same motion for
about 5 minutes then you can now open the white light. Continue the
fixing until the required time is finished. Next will be the washing and
drying of the negative.
This developing procedure is actually not recommended because the film
has a long contact with air during the procedure which can cause aerial
fog. Besides it is more tedious and tiring especially with a 36 exposure
film.
D. DEVELOPER FORMULATION
A typical components of a black and white developer are:
1. Solvent (water)
2. Developing agent
3. Preservatives
4. Accelerator
5. Restrainer
 Various chemicals can serve this function. Chemicals chosen
are determined whether it is slow or fast acting, procedure
high, normal, or low contrast, achieves maximum
emulsionspeed, creates fine grain or acts in a number of ways.
D-78 Film developer formula
1. Water 52C or 125 F - 750 ml
2. Elon - 2 grams
3. Hydroquinone - 5 grams
4. Sodium sulfite - 100 grams
5. Borax (granules) - 1 liter
DEKTOL- Paper Developer
1. Water 52C or 125 F - 500 grams
2. Elon - 311 grams
3. Hydroquinone - 12 grams
4. Sodium sulfite - 4.5 grams
5. Sodium carbonate - 67.5 grams
6. Potassium bromide - 1 gram
7. Water to make - 1 liter
E. STOP-BATH
Stop-can can be plain water only with 28% glacial acetic acid
F. FIXING BATH FORMULA
The chemical components of a fixing bath are:
1. Water
2. Dissolving agent
3. Preservative
4. Neutralizers
5. Hardener
A typical fixer formula
1. Water 50C or 125 F - 600ml
2. Hypo (sodium thiosulfate) - 240 gms.
3. Sodium sulfite (anyhydrous) - 15 gms.
4. Acetic acid (28%) - 480 ml.
5. Boric Acid (crystals) - 7.5 gms.
6. Potassium amum (fine granular) - 15 gms.
7. Water to make - 1liter
G. PHOTOGRAPHIC PRINTING
There are two general types of photographic printing:
1. Contact printing- Contract printing is the procedure of
exposing photographic print materials while it is pressed in
contact with the negative being reproduced. This is simplest
and the most economical method of photographic printing. In
terms of print quality, it can surpass enlargement in tonality
because there is no scattering of image forming lights as this
can be in projected beams of an enlarger. It usually looks
sharper because there is no lens in the printing system to add
its aberrations in the print making process and also because
details that may be slightly out of focus are not enlarged so the
unsharpness is not apparent.
Contact prints may be made with:
Glass and pad- A sheet of clear glass about 2 inches bigger
than the print size in all sides to give a border for handling and
for its application of pressure. The pad should be of the same
size as the glass.
Pressure printing frame- This is like a picture with a removable
hinge back leaf spring on the back. Lock it into place and it exert
pressure against the glass in the frame.
Contact printer- For a large volume work and a more
controlled printing a contact printer is most effective and
convenient. This essentially a glass-top box with an exposing
light and a safelight ( for proper arrangement of the negatives
and the paper ) inside and a hinge pressure cover on the glass.
Switches of the format control the lights.
Printing Procedure
Clean the glass from dust, dirt and stains. Place the negative
with the base side against the glass and the emulsion facing the
emulsion of the photographic paper. If a film rather than a
photographic paper is being exposed, it must be backed with a
black paper so reflected lights will not add unwanted exposure,
arrange the negatives to be printed on the photographic paper
so every part of it is accommodated with extra space on all
sides.
2. Projection Printing or Enlarging
This is a type of printing where the image in aa negative is
optically projected or enlarged onto a print material for exposure
to produce a picture image. The main equipment used is the
enlarger.
The basic or essential parts of an enlarger are:
1. Baseboard and its vertical column
2. Lamphouse
3. Condenser or diffuser
4. Bellows
5. Lens
6. Focusing knob
7. Elevating knob
8. Red filter
9. Electrical cord and switch
Essential accessory of an enlarger:
1. Negative carrier
2. Easel or paper holder
3. Timer for consistent and repeatable exposure
There are different sizes of enlargers. The size of the enlarger is
dependent on the size of the negative it is capable of accepting.
There is the 8mm for microfilms, the 35 mm which is now the
most common and popular, the 120mm or the bigger negatives
sizes like 4”x5”.
The common lights sources for enlargers are:
1. Tungsten lamp
2. Halogen lamp
3. Mercury vapor lamp
4. Fluorescent lamp sometimes referred to as “cold light”
because of its somewhat diffused illumination. This generally
used portrait work.
There are two general types of enlarger:
1. Diffusion type
2. Condenser type
H. ENLARGING PROCEDURE FOR BLACK AND WHITE
NEGATIVE
Before undertaking the enlarging procedure, mix or prepare the
chemical solution according to specifications; the negative; and
the enlarger, and the darkroom which must be clean and in
proper order.
The fundamental steps in enlarging are as follows:
1. Clean both of the negatives then place it in the negative carrier with the
emulsion (dull side ) facing the lens of the enlarger or downward position.
Insert the negative in the enlarger.
2. Adjust the masking guides of the easel in accordance with the intended
size to be printed.
3. Turn on the red light ( safelights ) then turn off the white light.
4. Switch on the enlarger then adjust the lens of the enlarger to its widest
aperture. ( this will allow the brightest image on the easel).
5. Adjust focus by rotating the focusing knob. For desired size of the image,
adjust the elevating knob. For bigger magnification, push the enlarger up
and for smaller magnification, pull the enlarger down, and then tighten the
elevating knob securely. Focus may now be finely readjusted.
6. Switch off the enlargers lights. Close down the lens aperture two or three
times from its optimum aperture ( be guided by its click stop adjustment)
7. If this is the first time that the negative is being printed, make
a series of test strips or trial exposures on strips of photographic
papers exposed at different exposure time generally 2 seconds
interval each. Make sure that the photographic papers are
placed in the easel emulsion side ( shiny side ) up when making
the exposure.
8. Process the test strips by immersing it in the developing
solution for 1 to 1 ½ minutes .
9. When the right exposure had been selected, make full print.
Process it then evaluate the print for over-all quality. Consider
for possible cropping, or local exposure control.
Cropping- is the excluding or omitting some images on the
negative from the final print.
Burning- is the adding of exposure time on a specific area to
bring out details.
Dodging- is the holding back of some lights to a specific area to
make it lighter in density.
Some factors that affect developing time:
a. Concentration and freshness of the chemical solution.
b. Temperature
c. Agitation
10. Current fixing baths only require 10-15 minutes fixing time.
Formerly it was 20-30 minutes.
11. Wash the prints in running water for another 20-30 minutes.
12. Dry the prints.
I. EQUIPMENT FOR PAPER DEVELOPING
1. Three plastic trays – one each for developer , stop-bath and the
fixer.
2. Metal, plastic or bamboo tong preferably with rubber ends to hold
the prints.
3. Rubber (surgical) hands gloves.
4. Timers
5. Paper cutter
6. A bigger tray or tank for washing prints
J. COLOR PRINTING PROCESS
A color negative film is printed on a color photographic paper
which is essentially similar to the films used in a camera except
that the emulsion layer is coated in a paper base and couplers
which are colorless.
The blue sensitivity layer produces a yellow color when
developed.
The green sensitive layer produces a magenta color when
developed.
The red sensitive layer produces cryan color when developed.
 1. Color film processing
 2. Color printing
 A. Equipment
 1. Enlarger with built dial in filter or with provision for placing
filters between the light source and negative.
 2. Color Photographic papers
 3. Filters- acetate color printing filters (CP) like CP2B (always
used to absorb ultraviolet rays from the light source).
 4.Safelights- Kodak safelights filters No. 13 (amber) with 15
watts bulb.
 B. Printing procedure in color printing of a negative.
 1. Prepare the chemical solutions by carefully following the
instructions given with the photographic paper and chemicals.
 2. Place the negative in the enlarger with emulsion side
toward the lens of the enlarger.
 3. Process the print then dry.
 4. Then judge the best test strip for color balance. Look at
sensitive areas or at the middle as flesh tones or persons and
decide on what color or colors is in excess and how much is
excess-light, considerable, great.
 5. Based on the above decision, select a filter pack that will
control the color of the exposing light.
K. COLOR COMPARED TO BLACK AND WHITE
 It is only natural and general we find color photographs more
realistic than black and white photographs.
 Black and white photograph are more of an abstraction from
reality, or in other words they ae commonly accepted on their
merits as pictures.
 In forensic photography, generally fingerprints and
handwritings or other printed materials which are subject for
examination, analysis, comparison and evaluation are black
and white (for contrast) in their original appearance so the use
of color photographs is not advice.
 1. Problems in color photography.
 A. Color quality of illumination
Essentially, the problem in color work is the fact that a color film does
not “see” color as the human eye.
B. Subject contrast
Subject contrast of a film depends largely on one factor-lighting
contrast which is the ratio between the highest and lowest amount of
illumination falling on the principal subject.
C. Exposure accuracy
Color films, particularly the reversal type have much less exposure
latitude than black and white film.
D. Color perception
Inexperienced observer sometimes cannot recognize subtle tints
mixtures and reflection brought about by the effects of lighting
condition and their surroundings.
E. Color harmony
Is the systematic arrangement of colors to give a pleasing effects.
F. Color blindness
Reporters:
1. Quezon A. Ahmad
2. Abubakar S. Undug
3. Ahmed Rashdee T. Indal
4. Abdurahman B. Hamjari

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Criminology review FORENSIC SCIENCE.pptx

  • 1. Forensic Photography Chapter 5 Photographic Printing and Chemical Processing
  • 2. A. CHEMICAL PROCESSING After the exposure of the film to light in the picture taking, the next step would generally be chemical processing. Black and White Processing- development, stop-bath, and fixation. Color Processing- development, stop-fix, and stabilizer.
  • 3. 1. Development- is the process by which an invisible latent image in an emulsion is made visible. B & W Emulsion- the image is composed of grains of black metallic silver. Color Emulsion- the developed silver is replaced with cyan, yellow, and magenta dye. 2. Stop-bath - halts the developer action in appropriate moment. It also prevents the contamination of the developer and fixer from each other. 3. fixation- makes the developed image permanent when it is followed by a thorough washing. In this processing stage, the unexposed undeveloped silver halides crystals are dissolved and removed from the emulsion of the photographic material.
  • 4. B. FILM PROCESSING It can be carried out in trays, tanks, or mechanized equipment. Panchromatic materials- handled in total darkness. Blue films, orthochromatic films and printing papers-handled under a safelight. 1.Equipment for film processing a.Tank or tray b.Developing reel c.Opener for film cartridge (pliers) d.Scissors to cut the tongue of the film e.Thermometer f. Timer g. Funnel h. Photographic sponge i. Films clips for drying j. Glass or plastic bottles for storing mixed solution.
  • 5. Tank Tray Developing reel Opener/ pliers Photographic sponge
  • 6.  Small format films like .35 mm is best developed in a cylindrical daylight developing tank that accommodates a spiral reel. Metal reels- have a center lip or hook to hold one end of the film, the remaining length slips into the grooves created by the spiral. Plastic reel- is loaded by simply pushing the film into the spiral from the outer end.
  • 7. C. FILM PROCESSING PROCEDURE 1. Tank method of the film development a.Mix the developer, stop-bath, and the fixer according to instructional manuals. Then bring it to temperature which is 20-21 C or 68-70 F. b.In a dry area, lay out the film, opener, scissors, reel and the tank so they can be readily located in the dark. c.In complete darkness, open the film cartridge by simply prying off the cap opposite the end, where the long spool core protrudes.
  • 8. Reeling Procedure To load a metal spiral reel, hold the film with the emulsion side in or down loosely in one hand while the other hands holds the reel. Slightly squeeze the film width by pressing between the thumb and forefinger so it narrows just enough to fit into the reel. It is advised for beginners to practice with unwanted film several times, first with the light on. Once you get the feel of it, start the practice with eyes closed to simulate darkness until the exercise is perfected.
  • 9. d. After the reeling of the film is done place it inside the daylight developing tank then cover it. White light can now be opened. Remove the lid cover of the tank is full. After 5-6 minutes pour out the developer. e. Pour in the top-bath, agitate the tank some more and after 15- 20 seconds drain out stop-bath. Next is to pour in the fixing bath, after 15-20 minutes drain the fixer from the tank. f. You now wash the negative for several changes. g. Remove the negative from the developing reel. Water that adheres on the surface of the negative cause watermarks if allowed to dry without wiping. h. Hang the negative to dry at a clean, dust free place or better in a negative drier.
  • 10. Tank method of film Development
  • 11. 2.Tray method of film development With this method of film development, the developer is placed on a tray. In total darkness, remove the film from the cartridge then hold one end of the film is thoroughly dipped until the whole length of the film is evenly wet. Timer will start now. With see-saw or pulling up or down motion, move the film from one end to the other then back, continuously, until the developing time of 4-5 minutes is done. Then transfer it to the stopbath for 10-15 seconds with the same motion. Thereafter, place the film in the fixer and execute same motion for about 5 minutes then you can now open the white light. Continue the fixing until the required time is finished. Next will be the washing and drying of the negative.
  • 12. This developing procedure is actually not recommended because the film has a long contact with air during the procedure which can cause aerial fog. Besides it is more tedious and tiring especially with a 36 exposure film. D. DEVELOPER FORMULATION A typical components of a black and white developer are: 1. Solvent (water) 2. Developing agent 3. Preservatives 4. Accelerator 5. Restrainer
  • 13.  Various chemicals can serve this function. Chemicals chosen are determined whether it is slow or fast acting, procedure high, normal, or low contrast, achieves maximum emulsionspeed, creates fine grain or acts in a number of ways. D-78 Film developer formula 1. Water 52C or 125 F - 750 ml 2. Elon - 2 grams 3. Hydroquinone - 5 grams 4. Sodium sulfite - 100 grams 5. Borax (granules) - 1 liter
  • 14. DEKTOL- Paper Developer 1. Water 52C or 125 F - 500 grams 2. Elon - 311 grams 3. Hydroquinone - 12 grams 4. Sodium sulfite - 4.5 grams 5. Sodium carbonate - 67.5 grams 6. Potassium bromide - 1 gram 7. Water to make - 1 liter E. STOP-BATH Stop-can can be plain water only with 28% glacial acetic acid
  • 15. F. FIXING BATH FORMULA The chemical components of a fixing bath are: 1. Water 2. Dissolving agent 3. Preservative 4. Neutralizers 5. Hardener
  • 16. A typical fixer formula 1. Water 50C or 125 F - 600ml 2. Hypo (sodium thiosulfate) - 240 gms. 3. Sodium sulfite (anyhydrous) - 15 gms. 4. Acetic acid (28%) - 480 ml. 5. Boric Acid (crystals) - 7.5 gms. 6. Potassium amum (fine granular) - 15 gms. 7. Water to make - 1liter
  • 17. G. PHOTOGRAPHIC PRINTING There are two general types of photographic printing: 1. Contact printing- Contract printing is the procedure of exposing photographic print materials while it is pressed in contact with the negative being reproduced. This is simplest and the most economical method of photographic printing. In terms of print quality, it can surpass enlargement in tonality because there is no scattering of image forming lights as this can be in projected beams of an enlarger. It usually looks sharper because there is no lens in the printing system to add its aberrations in the print making process and also because details that may be slightly out of focus are not enlarged so the unsharpness is not apparent.
  • 18. Contact prints may be made with: Glass and pad- A sheet of clear glass about 2 inches bigger than the print size in all sides to give a border for handling and for its application of pressure. The pad should be of the same size as the glass. Pressure printing frame- This is like a picture with a removable hinge back leaf spring on the back. Lock it into place and it exert pressure against the glass in the frame. Contact printer- For a large volume work and a more controlled printing a contact printer is most effective and convenient. This essentially a glass-top box with an exposing light and a safelight ( for proper arrangement of the negatives and the paper ) inside and a hinge pressure cover on the glass. Switches of the format control the lights.
  • 19. Printing Procedure Clean the glass from dust, dirt and stains. Place the negative with the base side against the glass and the emulsion facing the emulsion of the photographic paper. If a film rather than a photographic paper is being exposed, it must be backed with a black paper so reflected lights will not add unwanted exposure, arrange the negatives to be printed on the photographic paper so every part of it is accommodated with extra space on all sides.
  • 20. 2. Projection Printing or Enlarging This is a type of printing where the image in aa negative is optically projected or enlarged onto a print material for exposure to produce a picture image. The main equipment used is the enlarger. The basic or essential parts of an enlarger are: 1. Baseboard and its vertical column 2. Lamphouse 3. Condenser or diffuser 4. Bellows 5. Lens 6. Focusing knob 7. Elevating knob 8. Red filter 9. Electrical cord and switch
  • 21. Essential accessory of an enlarger: 1. Negative carrier 2. Easel or paper holder 3. Timer for consistent and repeatable exposure
  • 22. There are different sizes of enlargers. The size of the enlarger is dependent on the size of the negative it is capable of accepting. There is the 8mm for microfilms, the 35 mm which is now the most common and popular, the 120mm or the bigger negatives sizes like 4”x5”. The common lights sources for enlargers are: 1. Tungsten lamp 2. Halogen lamp 3. Mercury vapor lamp 4. Fluorescent lamp sometimes referred to as “cold light” because of its somewhat diffused illumination. This generally used portrait work.
  • 23. There are two general types of enlarger: 1. Diffusion type 2. Condenser type H. ENLARGING PROCEDURE FOR BLACK AND WHITE NEGATIVE Before undertaking the enlarging procedure, mix or prepare the chemical solution according to specifications; the negative; and the enlarger, and the darkroom which must be clean and in proper order.
  • 24. The fundamental steps in enlarging are as follows: 1. Clean both of the negatives then place it in the negative carrier with the emulsion (dull side ) facing the lens of the enlarger or downward position. Insert the negative in the enlarger. 2. Adjust the masking guides of the easel in accordance with the intended size to be printed. 3. Turn on the red light ( safelights ) then turn off the white light. 4. Switch on the enlarger then adjust the lens of the enlarger to its widest aperture. ( this will allow the brightest image on the easel). 5. Adjust focus by rotating the focusing knob. For desired size of the image, adjust the elevating knob. For bigger magnification, push the enlarger up and for smaller magnification, pull the enlarger down, and then tighten the elevating knob securely. Focus may now be finely readjusted. 6. Switch off the enlargers lights. Close down the lens aperture two or three times from its optimum aperture ( be guided by its click stop adjustment)
  • 25. 7. If this is the first time that the negative is being printed, make a series of test strips or trial exposures on strips of photographic papers exposed at different exposure time generally 2 seconds interval each. Make sure that the photographic papers are placed in the easel emulsion side ( shiny side ) up when making the exposure. 8. Process the test strips by immersing it in the developing solution for 1 to 1 ½ minutes . 9. When the right exposure had been selected, make full print. Process it then evaluate the print for over-all quality. Consider for possible cropping, or local exposure control.
  • 26. Cropping- is the excluding or omitting some images on the negative from the final print. Burning- is the adding of exposure time on a specific area to bring out details. Dodging- is the holding back of some lights to a specific area to make it lighter in density. Some factors that affect developing time: a. Concentration and freshness of the chemical solution. b. Temperature c. Agitation
  • 27. 10. Current fixing baths only require 10-15 minutes fixing time. Formerly it was 20-30 minutes. 11. Wash the prints in running water for another 20-30 minutes. 12. Dry the prints. I. EQUIPMENT FOR PAPER DEVELOPING 1. Three plastic trays – one each for developer , stop-bath and the fixer. 2. Metal, plastic or bamboo tong preferably with rubber ends to hold the prints. 3. Rubber (surgical) hands gloves. 4. Timers 5. Paper cutter 6. A bigger tray or tank for washing prints
  • 28. J. COLOR PRINTING PROCESS A color negative film is printed on a color photographic paper which is essentially similar to the films used in a camera except that the emulsion layer is coated in a paper base and couplers which are colorless. The blue sensitivity layer produces a yellow color when developed. The green sensitive layer produces a magenta color when developed. The red sensitive layer produces cryan color when developed.
  • 29.  1. Color film processing  2. Color printing  A. Equipment  1. Enlarger with built dial in filter or with provision for placing filters between the light source and negative.  2. Color Photographic papers  3. Filters- acetate color printing filters (CP) like CP2B (always used to absorb ultraviolet rays from the light source).  4.Safelights- Kodak safelights filters No. 13 (amber) with 15 watts bulb.
  • 30.  B. Printing procedure in color printing of a negative.  1. Prepare the chemical solutions by carefully following the instructions given with the photographic paper and chemicals.  2. Place the negative in the enlarger with emulsion side toward the lens of the enlarger.  3. Process the print then dry.  4. Then judge the best test strip for color balance. Look at sensitive areas or at the middle as flesh tones or persons and decide on what color or colors is in excess and how much is excess-light, considerable, great.  5. Based on the above decision, select a filter pack that will control the color of the exposing light.
  • 31. K. COLOR COMPARED TO BLACK AND WHITE  It is only natural and general we find color photographs more realistic than black and white photographs.  Black and white photograph are more of an abstraction from reality, or in other words they ae commonly accepted on their merits as pictures.  In forensic photography, generally fingerprints and handwritings or other printed materials which are subject for examination, analysis, comparison and evaluation are black and white (for contrast) in their original appearance so the use of color photographs is not advice.
  • 32.  1. Problems in color photography.  A. Color quality of illumination Essentially, the problem in color work is the fact that a color film does not “see” color as the human eye. B. Subject contrast Subject contrast of a film depends largely on one factor-lighting contrast which is the ratio between the highest and lowest amount of illumination falling on the principal subject. C. Exposure accuracy Color films, particularly the reversal type have much less exposure latitude than black and white film. D. Color perception Inexperienced observer sometimes cannot recognize subtle tints mixtures and reflection brought about by the effects of lighting condition and their surroundings. E. Color harmony Is the systematic arrangement of colors to give a pleasing effects. F. Color blindness
  • 33. Reporters: 1. Quezon A. Ahmad 2. Abubakar S. Undug 3. Ahmed Rashdee T. Indal 4. Abdurahman B. Hamjari