Lesson Plan
Course Title:
Printing & Imaging Technology
Session Title:
Digitally Capturing Images with a Flatbed
Scanner: Issues with Resolution
* This is Lesson #11 if used as part of the overall unit on Printing & Imaging Technology.
However, this lesson may be taught as a stand-alone project if desired.
Lesson Duration:
Approximately two to three 90-minute class periods
[Lesson length is subjective and will vary from instructor to instructor]
Performance Objective: Upon completion of this assignment, the student will be able to scan a
photograph, achieve maximum quality, and resample for the appropriate application.
Specific Objectives:
1. Review the purpose and logic of a flatbed scanner.
2. Define standard digital graphic vocabulary and abbreviations.
3. Discuss issues related to scanner resolution.
4. Capture a photograph with a flatbed scanner and resample the image for various uses.
Preparation
TEKS Correlations:
§130.96
(1) The student applies academic knowledge and skills in printing and imaging projects. The
student is expected to:
(A) apply English language arts knowledge and skills by demonstrating use of content,
technical concepts, and vocabulary; using correct grammar, punctuation, and
terminology to write and edit documents; and composing and editing copy for a
variety of written documents such as brochures, programs, and newsletters; and
(B) apply mathematics knowledge and skills by identifying whole numbers, decimals,
and fractions applied to measurement and scale; demonstrating knowledge of
arithmetic operations; using conversion methods such as fractions to decimals and
inches to points; and applying measurement to solve a problem.
(4)
The student applies information technology applications. The student is expected to use
personal information management, email, Internet, writing and publishing, presentation,
and spreadsheet or database applications for printing and imaging projects.
(11) The student develops a technical understanding of printing and imaging. The student is
expected to:
(G) prepare products for printing;
(H) demonstrate knowledge and appropriate use of hardware components, software
programs, and storage devices;
(I) demonstrate knowledge of file and cross-platform compatibility; and
(J) deliver products in a variety of media.
AAVTC: Printing and Imaging Technology: Digitally Capturing Images with a Scanner
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Instructor/Trainer
References:
Author’s expertise
Search online for scanning tips and other resources related to scanning.
Instructional Aids:
Digitally Capturing Images with a Flatbed Scanner slide presentation
Digitally Capturing Images with a Flatbed Scanner Performance Exam
Digitally Capturing Images with a Flatbed Scanner Written Exam
Digitally Capturing Images with a Flatbed Scanner Exam Key
Materials Needed:
Photographs to be scanned
The teacher may bring in a variety of photographs
The teacher may ask students to bring in several photographs
Equipment Needed:
Computer with projection device and presentation software
Flatbed scanner (a lab with more than one scanner would be optimal for this lesson)
Student computers with industry-standard photo editing software
Learner
Students should complete previous lessons in this course prior to working through this lesson.
Introduction
MI
Introduction (LSI Quadrant I):
ASK:
How many of you have ever copied a picture or made a photographic copy using
a scanner? (Anticipate that almost all students will raise their hands.)
ASK:
How many of you have tried to resize the picture, once it is copied?
ASK:
What have been some of your experiences?
SAY:
We have already established that it is important in graphic communications
that we get the best possible image on paper for our clients. Now we need to
take our skills to the next level. To get a professional-level image, we need a
thorough understanding of resolution and line screen.
Outline
MI
Outline (LSI Quadrant II):
Instructor Notes:
I. Review the purpose and logic of a flatbed scanner.
A. The purpose of flatbed scanners is to digitize
photographs or artwork.
Use the slide
presentation to
cover the concepts
AAVTC: Printing and Imaging Technology: Digitally Capturing Images with a Scanner
Copyright © Texas Education Agency, 2013. All rights reserved.
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B. This process will divide the image into a determined
number of pixels.
C. A pixel can only designate on finite flat color.
D. Pixels used for scanners, monitors, and print output
are perfectly square. Video pixels are 90% as wide as
they are tall.
II. Define standard digital graphic vocabulary and
abbreviations.
A. Resolution
1. The term resolution refers to the number of pixels
used to digitally represent an image.
2. Resolution can be expressed by the width and
height in pixels.
3. Resolution can also be expressed in pixels per inch
(ppi).
B. Computer monitors
1. Most computer monitors can be set at many different
resolutions depending on the type and expense of the
monitor.
2. Fifteen inch monitors are normally set at 800 pixels
horizontally by 600 pixels vertically.
3. Seventeen inch monitors are normally set at 1024
pixels by 768 pixels.
4. Monitor size is measured diagonally in inches and a
small portion of the screen is not viewable.
C. Line screen
1. Dots per inch (dpi) are common measurements for
inkjet and laser desktop printers, but commercial
printers usually use line screen measured in lines per
inch (lpi).
2. The amount of lines per inch (lpi) will vary depending
on the printer and, more importantly, the type or paper
that is used.
3. Common line screen settings
a. newspaper – 85 lpi
b. quick print – 110 lpi
c. commercial print – 133 lpi
d. magazines – 150 lpi
e. high end books – 200 lpi
4. Resolution/Line screen
a. The general rule for determining the resolution in
pixels needed for commercial printing is twice the
line screen.
b. ppi = 2 x lpi
c. If we are printing to a magazine stock that uses a
150 line screen, we would capture the image at 300
ppi.
D. Necessary resolution
1. Most inkjet printers and laser printers can handle a
in the outline.
Use the slide
presentation to
discuss
terminology.
(Slides 3 – 11)
AAVTC: Printing and Imaging Technology: Digitally Capturing Images with a Scanner
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resolution of between 200 and 300dpi.
2. Anything over 300 ppi is overkill.
a. Web – 72 ppi
b. Newspaper – 170 ppi
c. Commercial print – 266 ppi
d. Inkjet/laser or magazine print – 300 ppi
III. Discuss issues related to scanner resolution.
A. Flatbed scanner specifications are stated with two
numbers, like 1200 x 2400 dpi.
B. A scanner scans one horizontal row of pixels at a time,
moving that scan line down the page with a carriage
motor.
C. The smaller dpi number is the optical resolution of the
scanner, the number of sensors that fit across the
carriage.
D. The best flatbed scanners use Charge Coupled Device
(CCD) sensor cells.
E. The larger dpi number is the possible positioning of the
carriage stepping motor. A 1200 x 2400 dpi scanner
moves in 1/2400 inch steps vertically.
F. If a scanner has an optical resolution of 600 ppi (600
sensors across the carriage) and we ask it to scan at a
resolution of 300 ppi, everything works great.
G. In this scenario, we would have two sensors actually
determine one pixel. If we scan at 290 ppi, things do
not work as well.
H. To get the best available image, we always want to
use a resolution that is a multiple of the optical
resolution.
I. Acceptable settings for a 600 ppi optical resolution
scanner would be 150 ppi, 200 ppi, and 300 ppi.
J. When using most scanners, it is usually always a good
idea to scan at 300 ppi for photographs.
Use the slide
presentation to
discuss concepts
related to scanner
resolution.
IV. Capture a photograph with the use of a flatbed scanner
and resample the image for various uses.
A. Place the image in the scanner.
B. Launch through the appropriate software (scanner
software driver)
C. Save the scanned image. Then save a copy of the
image to edit. (Never edit the original.)
D. Use resampling techniques to adjust the copy of the
scanned image for various outputs.
Go over the
process verbally
prior to beginning
the guided practice
activities. Use the
slide presentation
to guide the
process discussion.
Application
AAVTC: Printing and Imaging Technology: Digitally Capturing Images with a Scanner
Copyright © Texas Education Agency, 2013. All rights reserved.
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MI
Guided Practice (LSI Quadrant III):
Teacher shows and demonstrates scanning and resampling techniques multiple
times. The first demonstration should be 100% teacher led. The second
demonstration should be guided by the students with the teacher performing the
steps as instructed by the students and verified and corrected as necessary by the
teacher. The third demonstration should be 100% directed by the students (or
performed by a student volunteer while the rest of the class guides the process).
If you are limited in the number of scanners you have in your lab, allow students to
practice resampling techniques on existing image files while they are waiting to work
with the scanner.
The teacher will maintain direct supervision of lab providing guidance when needed.
MI
Independent Practice (LSI Quadrant III):
Using photo-editing software, a flatbed scanner, and a photograph supplied by the
instructor, the students will each digitize the photograph at print resolution. The
image should be saved using the .tif file format (This is your original).
Using the software, the student will resample the image to a width of no more than
400 pixels for use on the internet. The image should be saved using the jpeg file
format.
The student will place the jpeg image in a desktop publishing application and print on
a color inkjet or color laser printer.
Summary
MI
Review (LSI Quadrants I and IV):
Checking for understanding:
Review the vocabulary related to the lesson using the slide presentation
Conduct a question and answer session.
Q: What resolution is needed for documents used in web-based applications?
A: Resolution needed for web applications is usually no larger than 400 to 600
pixels in width or height.
Q: What resolution is needed for inkjet or laser printers?
A: Resolution needed for inkjet or laser printers is between 200 and 300 ppi.
Q: What method is used to determine the resolution needed for something that will be
printed on a press?
A: Resolution needed for printing presses is twice the line screen.
Q: How do you determine line screen?
A: Line screen is determined by the paper used.
Q: What is the best formula for ensuring a quality scan?
A: Scanners give the best quality when images are scanned at the optical resolution
of a resolution that divides easily into the optical resolution.
Q: What is the best method of scanning a document for general use?
AAVTC: Printing and Imaging Technology: Digitally Capturing Images with a Scanner
Copyright © Texas Education Agency, 2013. All rights reserved.
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A: Scanning can usually be done at 300 ppi and then resampled down in Photoshop
to match the final output.
Q: When is high resolution scanning (over 300 ppi) useful?
A: High resolution scanning (over 300 ppi) is useful when scaling an object to a
larger than original size or when scanning line art.
Evaluation
MI
Informal Assessment (LSI Quadrant III):
The teacher will monitor student progress during Independent Practice and provide
independent assistance when needed. Teacher may choose to give a formative
grade based on the final student output from the guided practice.
MI
Formal Assessment (LSI Quadrant III, IV):
Administer the performance exam and the written exam.
Extension
MI
Extension/Enrichment (LSI Quadrant IV):
Students who have mastered the skills can serve as peer-tutors to students needing
assistance.
In addition to scanning photos, the students can also scan artwork, drawings, and
paintings. Scanning in a drawing and allowing the student to digitally enhance, using
photo-editing software will add another artistic element to their portfolios.
Students who are interested in developing this skill can explore additional techniques
and tools in the software tutorial.
AAVTC: Printing and Imaging Technology: Digitally Capturing Images with a Scanner
Copyright © Texas Education Agency, 2013. All rights reserved.
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Digitally Capturing Images with a Flatbed Scanner
Performance Exam
DIRECTIONS: Complete the following steps using photo-editing software, a flatbed scanner, and the
photograph supplied by your instructor. Save all files to your student folder. Evaluation based on
following rubric.
1. Digitize the photograph at print resolution. The image should be saved using the .tif file
format.
2. Using the software, resample the image to a width of no more than 400 pixels for use on the
Internet. The image should be saved using the jpeg file format.
3. Place the jpeg image in a desktop publishing application and print on a color inkjet or color
laser printer.
Criteria
Above
Average
15-26 points
Below
Average
1-14 points
Photograph was
scanned using
the TWAIN driver
at the proper
resolution.
Photograph was
scanned using
the TWAIN driver
but the resolution
was not set
properly.
Photograph was
not scanned
using the TWAIN
driver.
No attempt made
to scan the
photograph.
27-30 points
15-26 points
1-14 points
0 points
Image resampled
using software;
width is no more
than 400 pixels.
Image resampled
using software
but width is more
than 400 pixels.
Image resized
but not
resampled in
software.
No attempt made
to resample the
image.
17-20 points
8-16 points
1-7 points
0 points
Resampled image
appropriately
placed in a
desktop
publishing file and
printed as
instructed.
Resampled
image
appropriately
placed in a
desktop
publication but
not printed as
instructed.
Resampled
image printed
from an
inappropriate
software
application.
No attempt to
place or print
image.
17-20 points
8-16 points
1-7 points
0 points
Files saved
according to
instructions and
stored in student
folder.
Files saved
according to
instructions but
not stored in
student folder.
One file saved
according to
instructions and
stored in student
folder.
None of the files
saved as
instructed or
stored in student
folder.
Exceptional
Above
Average
Below
Average
Exceptional
27-30 points
Scanning
(30 pts)
Resampling
(30 pts)
Printing
(20 pts)
Technical
(20 pts)
Criteria
Unacceptable
0 points
TOTAL
AAVTC: Printing and Imaging Technology: Digitally Capturing Images with a Scanner
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Points
Digitally Capturing Images with a Flatbed Scanner
Written Exam
DIRECTIONS: Circle the letter that corresponds to the best answer for each of the questions or
statements below (3 points each).
1.
Digital representation of a graphical image is commonly referred to as
A. Line screen
B. Pixel
C. Resolution
D. Leading
2.
The number of lines of dots that appear per linear inch on a printed piece is called
the
.
A. Line screen
B. Pixel
C. Resolution
D. Leading
3.
is a single square in a graphic image that can display one finite flat color.
A.
B.
C.
D.
Line screen
Pixel
Resolution
Leading
4.
A term that refers to the scanner software driver is
A. TWAIN
B. Resample
C. Diode
D. Optical resolution
5.
The number of sensors on the scanner carriage is the
A. TWAIN
B. Resample
C. Diode
D. Optical resolution
6.
A.
B.
C.
D.
7.
.
.
.
is a term that refers to adjusting the resolution of an image.
TWAIN
Resample
Diode
Optical resolution
LPI is a measurement used for
A. Inkjet and laser printers
B. Computer processors
C. Monitors and scanners
D. Commercial printers/imagesetters
.
AAVTC: Printing and Imaging Technology: Digitally Capturing Images with a Scanner
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8.
PPI is a measurement used for
A. Inkjet and laser printers
B. Computer processors
C. Monitors and scanners
D. Commercial printers/imagesetters
.
9.
DPI is a measurement used for
A. Inkjet and laser printers
B. Computer processors
C. Monitors and scanners
D. Commercial printers/imagesetters
.
10.
The resolution needed for a digital image should be
A. Less than
B. The same as
C. Two and a half times
D. Twice
11.
Monitors are usually measured
A. Horizontally across the screen in inches
B. Diagonally across the screen in inches
C. Diagonally across the screen in pixels
D. Vertically in centimeters
12.
The main factor that determines line screen is
A. Ink used in printing
B. Type of press
C. Paper used in printing
D. Color of ink
13.
The best quality sensor used in most desktop scanners is the
A. CIS
B. BIOS
C. CMOS
D. CCD
14.
Although it is a common practice to resample down after the original scan, a good scanning
resolution for photographs to use most of the time with most flatbed scanners is
.
A. 72 ppi
B. 500 ppi
C. 230 ppi
D. 300 ppi
15.
Which is not a good reason to scan at a resolution of 600 ppi?
A. To get the best quality out of an inkjet printer
B. To scale an image to a larger size than the original
C. To get the best quality from a hand drawn comic strip
D. To get the best quality image of a pencil sketch
the line screen.
.
.
AAVTC: Printing and Imaging Technology: Digitally Capturing Images with a Scanner
Copyright © Texas Education Agency, 2013. All rights reserved.
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.
Digitally Capturing Images with a Flatbed Scanner
Exam Key
1. C
2. A
3. B
4. A
5. D
6. B
7. D
8. C
9. A
10. D
11. B
12. C
13. D
14. D
15. A
AAVTC: Printing and Imaging Technology: Digitally Capturing Images with a Scanner
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