DIS DIS Quality Assurance & Testing 1 — Questions and Answers
Question 1: What is the purpose of a step wedge (gray scale) target in scanner quality assurance testing?
- To evaluate a scanner's ability to reproduce a range of tonal values from white to black accurately (Correct answer)
- To test the scanner's color filter alignment
- To measure scanning speed under load
- To verify the scanner's wireless connectivity
Correct answer: To evaluate a scanner's ability to reproduce a range of tonal values from white to black accurately
A step wedge target provides a series of known tonal steps that allow testers to verify a scanner's tonal accuracy and dynamic range.
Question 2: Which metric is used to measure the sharpness and resolving power of an imaging system?
- MTF (Modulation Transfer Function) (Correct answer)
- DPI (Dots Per Inch)
- Bit depth
- Color temperature
Correct answer: MTF (Modulation Transfer Function)
MTF (Modulation Transfer Function) quantifies how well an imaging system reproduces fine detail and contrast at various spatial frequencies.
Question 3: What does 'image noise' refer to in the context of digital imaging quality assurance?
- Random variation in brightness or color values in an image not present in the original scene (Correct answer)
- Unwanted audio recorded alongside image metadata
- File corruption caused by network transmission errors
- Excessive sharpening applied during post-processing
Correct answer: Random variation in brightness or color values in an image not present in the original scene
Image noise is random pixel-level variation in brightness or color that degrades image quality, often caused by sensor limitations or high ISO settings.
Question 4: In QA testing for a digital imaging workflow, what is a 'target image' used for?
- A standardized reference image used to verify and calibrate the accuracy of an imaging system (Correct answer)
- An image selected by the client as the final deliverable
- A low-resolution preview image used in web publishing
- A watermarked image used to track distribution
Correct answer: A standardized reference image used to verify and calibrate the accuracy of an imaging system
A target image is a standardized reference used during QA to verify that an imaging system produces accurate, consistent results matching known values.
Question 5: What is the function of Delta-E (ΔE) measurement in imaging quality assurance?
- It quantifies the perceptible color difference between a captured image and the reference target (Correct answer)
- It measures the file size difference between two image formats
- It calculates the compression ratio of a JPEG image
- It tests the response time of an imaging workstation
Correct answer: It quantifies the perceptible color difference between a captured image and the reference target
Delta-E (ΔE) is a numerical measure of the color difference between two images or color samples, with lower values indicating closer color accuracy.
Question 6: Which type of test chart is commonly used to assess the resolution of a digital camera or scanner?
- ISO 12233 resolution chart (Correct answer)
- Munsell color chart
- Kodak gray card
- Macbeth ColorChecker
Correct answer: ISO 12233 resolution chart
The ISO 12233 chart is the standard test chart for measuring the spatial resolution and sharpness of digital cameras and scanners.
DIS DIS Quality Assurance & Testing 1
What is the purpose of a step wedge (gray scale) target in scanner quality assurance testing?