Question: What standards did the DIN begin to use?
Answer: ISO standards

Question: When were the ISO standards first adopted?
Answer: in the 1980s

Question: When were the last ISO standards adopted? 
Answer: July 2002

Question: What system was used previous to the ASA system?
Answer: the system of Weston film speed ratings

Question: Who devised the Weston film speed ratings? 
Answer: Edward Faraday Weston (1878–1971) and his father Dr. Edward Weston (1850–1936)

Question: What company did Dr. Edward Weston start? 
Answer: the US-based Weston Electrical Instrument Corporation

Question: When was the Weston model 617 created?
Answer: August 1932

Question: Who is credited with creating the film and meter system?
Answer: William Nelson Goodwin, Jr.

Question: Which cameras were first of their type to adopt the ASA scale?
Answer: The Weston Cadet (model 852 introduced in 1949), Direct Reading (model 853 introduced 1954) and Master III (models 737 and S141.3 introduced in 1956)

Question: What were updated Weston values based on?
Answer: the ASA system

Question: How were Weston values changed to ASA values?
Answer: by subtracting 1/3 exposure stop

Question: Beginning with which year was the Weston to ASA conversion not necessary?
Answer: 1956

Question: Until what year did other models use the original Weston scale?
Answer: 1955

Question: Which company adopted the ASA scale in 1946?
Answer: General Electric

Question: Beginning what year were cameras built with the ASA meter?
Answer: 1946

Question: How did older models convert to ASA scale?
Answer: replaceable hoods with ASA scales

Question: How was the ASA scale shown on models built after 1946?
Answer: labeled "Exposure Index"

Question: What were recommended film values lined up with after 1946?
Answer: they were now aligned to the ASA scale

Question: Who pioneered research that led to the new ANSI values?
Answer: Loyd Ancile Jones

Question: What standards were the ANSI developed from?
Answer: Weston film speed ratings and General Electric film values

Question: What types of film did the ANSI measure?
Answer: black-and-white negative films

Question: When did the ANSI define its new measure?
Answer: 1943

Question: What were ANSI values often called in the beginning?
Answer: American standard speed numbers or ASA exposure-index numbers

Question: In what year were big changes made to the ANSI?
Answer: 1960

Question: What did the 1960 changes to film speed measures lead to?
Answer: effectively doubling the nominal speed of many black-and-white negative films

Question: Which other system were these changes applied to?
Answer: the DIN system

Question: In what year was the BS system modified?
Answer: 1963

Question: What safety factors were done away with beginning with the modifications to the standards?
Answer: safety factors against under-exposure

Question: What is the plot from which film speed is derived called?
Answer: the D–log H curve or Hurter–Driffield curve

Question: How many regions does the Hurter-Driffield curve have?
Answer: five

Question: What is plotted in the Hurter-Driffield curve?
Answer: a plot of optical density vs. log of exposure for the film

Question: What is denoted when the specified contrast condition is met?
Answer: The exposure Hm, in lux-s

Question: What are the five regions of the Hurter-Driffield curve?
Answer: the base + fog, the toe, the linear region, the shoulder, and the overexposed region

Question: What is the effective f-number proportional to?
Answer: the ratio between the lens focal length and aperture diameter

Question: What is used to discover the right exposure parameters?
Answer: Film speed

Question: What variables help the photographer produce the desired effect?
Answer: lighting, film speed, f-number (aperture size), and shutter speed (exposure time)

Question: A lens with a setting of f/1.4 lets how much to hit the focal plane compared with a setting of f/2?
Answer: twice as much

Question: In the APEX system, the increment that doubles the exposure is called what?
Answer: "stop"

Question: What determines the effect on the emulsion after exposure?
Answer: the amount of light energy that reaches the film

Question: In what range of exposures does reciprocity usually work?
Answer: between 1/1000 second to 1/2 second

Question: How is the exposure of film changed?
Answer: by varying the camera's shutter speed and aperture

Question: How are ways of finding an emulsion's sensitivity possible?
Answer: because reciprocity holds

Question: What happens outside the 1/1000 second to 1/second exposure range?
Answer: reciprocity failure

Question: What are two examples of films that are marketed with speeds above their true ISO speed?
Answer: Ilford Delta 3200 and Kodak T-MAX P3200

Question: What speed of film is the Ilford Delta 3200?
Answer: ISO 1000

Question: Which two companies produced E6 films meant for "pushing"?
Answer: Kodak and Fuji

Question: What is the base speed of Ektachrome P800/1600 and Fujichrome P1600?
Answer: ISO 400

Question: What type of films are Ilford Delta 3200 and Kodak T-MAX P3200?
Answer: high-speed black-and-white films

Question: What is another name for an exposure index rating?
Answer: ISO setting

Question: How do some camera designs give some EI choices?
Answer: by adjusting the sensor's signal gain in the digital realm

Question: Who provides the exposure index rating?
Answer: the manufacturer

Question: What are digital photo cameras also called?
Answer: digital still cameras

Question: What types of cameras have proven to be much more sensitive to light than film?
Answer: Digital cameras

Question: What ISO equivalent speeds can digital cameras obtain?
Answer: 409,600

Question: What is responsible for these vast increases in speed?
Answer: Faster processors, as well as advances in software noise reduction techniques

Question: What is one thing that limited speeds of older digital hardware?
Answer: prohibitively time consuming to process

Question: What does the higher speed do for the images produced?
Answer: a higher level of refinement

Question: How many techniques are available because of ISO 12232:2006?
Answer: five

Question: What techniques did CIPA DC-004 provide?
Answer: two new techniques allowing for measurement of JPEG output files

Question: What factors affect the exposure index rating?
Answer: the sensor sensitivity, the sensor noise, and the appearance of the resulting image

Question: What does the standard of ISO 12232:2006 specify?
Answer: the measurement of light sensitivity of the entire digital camera system and not of individual components

Question: In what year did Kodak start using a different way of characterizing two sensors?
Answer: 2001

Question: What option does the Recommended Exposure Index give manufacturers? 
Answer: to specify a camera model’s EI choices arbitrarily

Question: What is another name for multi-zone metering?
Answer: pattern metering

Question: What distinction does the Recommended Exposure Index have?
Answer: the only technique available under the standard for output formats that are not in the sRGB color space

Question: When was the Recommended Exposure Index introduced?
Answer: 2006

Question: What is the only technique that can be used when multi-zone metering is used?
Answer: Recommended Exposure Index (REI) technique

Question: What year was the Standard Output Sensitivity technique introduced?
Answer: 2006

Question: What does the Standard Output Sensitivity technique apply to?
Answer: sRGB images—typically JPEG

Question: What is the output level measured in?
Answer: the sRGB output from the camera

Question: With what type of metering can the Standard Output Sensitivity not be used?
Answer: multi-zone metering

Question: With what standard is the automatic exposure control system calibrated?
Answer: ISO 2721

Question: Which methods are required by CIPA DC-004?
Answer: REI or SOS techniques