scanning 101 and beyond media & instructional technology services darryl simcoe, instructor...

Scanning 101 and BeyondScanning 101 and Beyond

Media & Instructional Technology ServicesMedia & Instructional Technology Services

Darryl Simcoe, InstructorDarryl Simcoe, Instructor

Scanning: process of converting images to digital data files

• Display on computer monitor

• Reprint on paper or overhead

transparency

• Expose on photographic film

Scanning: process of converting images to digital data files

• Display on computer monitor

• Reprint on paper or overhead

transparency

• Expose on photographic film

Class GoalClass Goal

Convey essential information for

productive scanning.

Convey essential information for

productive scanning.

Build on basics as time permits.Build on basics as time permits.Build on basics as time permits.Build on basics as time permits.

Where do I begin?Where do I begin?

Start with the best quality original Start with the best quality original print or transparency available!print or transparency available!Start with the best quality original Start with the best quality original print or transparency available!print or transparency available!

--- "Golden Rule" of computing applies:

GIGO (garbage in, garbage out)

--- "Golden Rule" of computing applies:

GIGO (garbage in, garbage out)

I have my original, now what?

I have my original, now what?

Choose the right scanner!Choose the right scanner!--- Optimized for either reflective art or --- Optimized for either reflective art or

transparenciestransparencies -- Resolution varies (number of pixels per inch-- Resolution varies (number of pixels per inch

they can differentiate)they can differentiate)

-- Ability to differentiate gradations in-- Ability to differentiate gradations in

shadow areas variesshadow areas varies

Choose the right scanner!Choose the right scanner!--- Optimized for either reflective art or --- Optimized for either reflective art or

transparenciestransparencies -- Resolution varies (number of pixels per inch-- Resolution varies (number of pixels per inch

they can differentiate)they can differentiate)

-- Ability to differentiate gradations in-- Ability to differentiate gradations in

shadow areas variesshadow areas varies

--- Given a choice, use a --- Given a choice, use a transparencytransparency

scannerscanner for 35mm slides or film negatives; for 35mm slides or film negatives;

use a use a flatbed scannerflatbed scanner for reflective artwork for reflective artwork

--- Given a choice, use a --- Given a choice, use a transparencytransparency

scannerscanner for 35mm slides or film negatives; for 35mm slides or film negatives;

use a use a flatbed scannerflatbed scanner for reflective artwork for reflective artwork

Where can I find a scanner?Where can I find a scanner?

Flatbed scanners:Flatbed scanners:• ITS Computing Lab - O'Connor Campus CenterITS Computing Lab - O'Connor Campus Center• Media & Instructional Technology Services - Media & Instructional Technology Services -

McGregory SB-8 (two available)McGregory SB-8 (two available)• Keck Humanities Resource Center - Keck Humanities Resource Center -

Lawrence HallLawrence Hall

Flatbed scanners:Flatbed scanners:• ITS Computing Lab - O'Connor Campus CenterITS Computing Lab - O'Connor Campus Center• Media & Instructional Technology Services - Media & Instructional Technology Services -

McGregory SB-8 (two available)McGregory SB-8 (two available)• Keck Humanities Resource Center - Keck Humanities Resource Center -

Lawrence HallLawrence Hall

Slide/transparency scanner:Slide/transparency scanner:

• Media & Instructional Technology Services - Media & Instructional Technology Services -

McGregory SB-8McGregory SB-8

Slide/transparency scanner:Slide/transparency scanner:

• Media & Instructional Technology Services - Media & Instructional Technology Services -

McGregory SB-8McGregory SB-8

TerminologyTerminology

• Basic Terminology (see handout)• Basic Terminology (see handout)

• BitmapBitmap vs.vs. Vector (object-oriented) graphicsVector (object-oriented) graphics• BitmapBitmap vs.vs. Vector (object-oriented) graphicsVector (object-oriented) graphics

• HalftoneHalftone vs.vs. ContoneContone imagesimages• HalftoneHalftone vs.vs. ContoneContone imagesimages

• Resolution & Image sizeResolution & Image size• Resolution & Image sizeResolution & Image size

• Image ToneImage Tone• Image ToneImage Tone

• Bit depthBit depth• Bit depthBit depth

BitmapBitmap vs.vs. Vector (object-oriented) graphicsVector (object-oriented) graphicsA bitmap image consists of pixels, whose color and location on a grid determine the appearance of the image. When editing bitmapped images, we edit individual pixels.

A vector graphic is defined by mathematical objects called vectors, which determines the geometric characteristics of the graphic. When working with vector graphics, we edit shapes and objects rather than groups of pixels.

Bitmap images are good at reproducing the subtle shading found in continuous-tone images, such as photographs. However, they are resolution dependent and thus can show jagged edges when magnified or printed at a higher resolution then they were created for.

3:1 zoom 24:1 zoom

Vector graphics display or print at the resolution available on output device (printer, monitor, film recorder). As a result, vector graphics enlarge well and are good at reproducing crisp outlines and details.

3:1 zoom 24:1 zoom

Example of Example of

halftone grid halftone grid

representing representing

grayscale image.grayscale image. White Light gray spot Dark gray spot Black

(all dots off) (18.8%) (75%) (all dots on)

HalftoneHalftone vs.vs.

ContoneContone imagesimages

Example of Example of

a contonea contone

image:image:

Continuous-tone (contone) image: the color or gray Continuous-tone (contone) image: the color or gray shade of each pixel can be varied (each has its own shade of each pixel can be varied (each has its own specific color definition made by building up specific color definition made by building up varying densities of primary colors in the same spot)varying densities of primary colors in the same spot)

HalftoneHalftone vs.vs. ContoneContone imagesimages

Bit DepthBit Depth Bit DepthBit Depth

Bit Depth:Bit Depth: the particular number of bits (zeros the particular number of bits (zeros and/or ones) making up each pixel in a bitmapped and/or ones) making up each pixel in a bitmapped image; bit depth dictates the range of possible image; bit depth dictates the range of possible values for each pixel, and hence the total number values for each pixel, and hence the total number of colors (or shades gray) that the image can of colors (or shades gray) that the image can contain.contain.

Example of various bit depths:Example of various bit depths:

ResolutionResolution is the measure of detail in an image, is the measure of detail in an image, usually given in dots per inch (dpi) or pixels per usually given in dots per inch (dpi) or pixels per inch (ppi).inch (ppi).

Resolution & Image sizeResolution & Image size Resolution & Image sizeResolution & Image size

Image sizeImage size is conferred upon a bitmapped image. is conferred upon a bitmapped image. With size comes resolution. An image's resolution With size comes resolution. An image's resolution changes as the image's (physical) size is altered. changes as the image's (physical) size is altered. When making the image larger the pixels are When making the image larger the pixels are simply displayed larger; when making an image simply displayed larger; when making an image smaller, the pixels are crammed into a smaller smaller, the pixels are crammed into a smaller amount of space and each pixel is smaller.amount of space and each pixel is smaller.

Image pixel dimensions: 640 x 480 pixels

Print size: 288 ppi (2.22" x 1.67")

13" Monitor: 640 x 480 setting

15" Monitor: 640 x 480 setting15" Monitor: 832 x 624 setting

21" Monitor: 1024 x 768 setting 21" Monitor: 640 x 480 setting

Regardless of Regardless of specified print specified print size, on-screen size, on-screen image size is image size is determined by the determined by the pixel dimensionspixel dimensions of the image, the of the image, the monitor sizemonitor size, and , and the the monitor monitor resolution settingresolution setting..

Physical Size of Physical Size of

Images on a MonitorImages on a Monitor

Image tone isImage tone is the brightness, range, and balance of the brightness, range, and balance of reds, greens, and blues in an image; tone varies reds, greens, and blues in an image; tone varies depending on color balance, contrast between depending on color balance, contrast between highlights and shadows, and dimness or brightness highlights and shadows, and dimness or brightness of midtones (gamma variations)of midtones (gamma variations)

Tonal manipulation is the key to setting the right Tonal manipulation is the key to setting the right contrast for images. contrast for images.

Image ToneImage ToneImage ToneImage Tone

Things to know before you scan !Things to know before you scan !

• What is the intended use?• What is the intended use?

• What size (dimensions) do you want the image

to be when delivered?

• What size (dimensions) do you want the image

to be when delivered?

• What image type are you scanning?• What image type are you scanning?

• What file format should the image be saved as?• What file format should the image be saved as?

Knowing the following will help you set upyour software for best results:

Knowing the following will help you set upyour software for best results:

Intended use...Intended use...

What "imaging" process will be used toWhat "imaging" process will be used to

print, expose, or display the image?print, expose, or display the image?

•To be printed, exposed, or displayed?To be printed, exposed, or displayed?• Continuous tone or halftone process?Continuous tone or halftone process?

(see handout)(see handout)• Resolution of printer, film recorder or monitor?Resolution of printer, film recorder or monitor?• Type of paper if printing?Type of paper if printing?

What "imaging" process will be used toWhat "imaging" process will be used to

print, expose, or display the image?print, expose, or display the image?

•To be printed, exposed, or displayed?To be printed, exposed, or displayed?• Continuous tone or halftone process?Continuous tone or halftone process?

(see handout)(see handout)• Resolution of printer, film recorder or monitor?Resolution of printer, film recorder or monitor?• Type of paper if printing?Type of paper if printing?


Printing black-and-white line art

• Limit scan resolution to maximum resolution

of the printing device• Experiment with lower settings

• Best compromise betweem file size and quality• High resolution imagesetters: use 800 ppi

minimum, preferably 1000 + ppi• Exception: 400 to 600 ppi usually adequate if

printing to newsprint or other porous paper

Printing black-and-white line art

• Limit scan resolution to maximum resolution

of the printing device• Experiment with lower settings

• Best compromise betweem file size and quality• High resolution imagesetters: use 800 ppi

minimum, preferably 1000 + ppi• Exception: 400 to 600 ppi usually adequate if

printing to newsprint or other porous paper


Printing grayscale & color bitmapped

images on halftone devices (e.g., laser

printer or imagesetter)

• Limit scan to 2 times the printer's default

screen frequency• Often 1.5 times the screen frequency or

less will give adequate results (especially

on porous, uncoated paper or newsprint)

Printing grayscale & color bitmapped

images on halftone devices (e.g., laser

printer or imagesetter)

• Limit scan to 2 times the printer's default

screen frequency• Often 1.5 times the screen frequency or

less will give adequate results (especially

on porous, uncoated paper or newsprint)


Displaying on a computer monitor

• Limit image resolution to what the screen

can display• Default screen resolution is usually

72 ppi on Mac monitors and 96 ppi

on PC monitors•Rule of thumb: Use 75 ppi

Displaying on a computer monitor

• Limit image resolution to what the screen

can display• Default screen resolution is usually

72 ppi on Mac monitors and 96 ppi

on PC monitors•Rule of thumb: Use 75 ppi


Exposing or printing to continuous-tone

output devices (e.g., film recorders or dye-

sublimation printers)

• Ideally, match scan resolution to

output device resolution• Practically, doing so may result in an

unrealistically large file to work with• Seek an adequate compromise between

resolution and file size. (i.e., experiment!)

Exposing or printing to continuous-tone

output devices (e.g., film recorders or dye-

sublimation printers)

• Ideally, match scan resolution to

output device resolution• Practically, doing so may result in an

unrealistically large file to work with• Seek an adequate compromise between

resolution and file size. (i.e., experiment!)


Polaroid digital film recorder

• Import image into Powerpoint for exposing to film• Match the image dimensions to the PowerPoint

slide dimensions• Format slide background to black

Polaroid digital film recorder

• Import image into Powerpoint for exposing to film• Match the image dimensions to the PowerPoint

slide dimensions• Format slide background to black

What physical size (dimensions)?What physical size (dimensions)?

• Remember, image size is conferred Remember, image size is conferred

upon a bitmapped image. They have upon a bitmapped image. They have

no physical size (just a set number of no physical size (just a set number of

pixels) until you specify the height and pixels) until you specify the height and

width.width.

• Determine the desired output size and Determine the desired output size and

specify it in the software settings.specify it in the software settings.

What image type is being scanned...What image type is being scanned...

• Select software setting appropriatelySelect software setting appropriately

for the type of image desiredfor the type of image desired• Often the same as the original, butOften the same as the original, but

there are some exceptionsthere are some exceptions

What file format to save in?What file format to save in?

Know which file formats can be imported

into the software program you'll use to print

the final image.

Know which file formats can be imported

into the software program you'll use to print

the final image.

What makes a good scan...What makes a good scan...(and why you should care…)(and why you should care…)

• Image toneImage tone

• Color balanceColor balance

• ResolutionResolution

Examples of software setup:Examples of software setup:Apple Color Onescanner via Adobe PhotoshopApple Color Onescanner via Adobe PhotoshopExamples of software setup:Examples of software setup:Apple Color Onescanner via Adobe PhotoshopApple Color Onescanner via Adobe Photoshop

Examples of software setup:Examples of software setup:Sprintscan 35 (slide/transparency scanner)Sprintscan 35 (slide/transparency scanner)Examples of software setup:Examples of software setup:Sprintscan 35 (slide/transparency scanner)Sprintscan 35 (slide/transparency scanner)

Some tips...Some tips...

Tip: Don't use "brightness" or "contrast" Tip: Don't use "brightness" or "contrast" controls on images… too much data is controls on images… too much data is lost. Use on channels or masks only. lost. Use on channels or masks only. Instead, use Instead, use levels or curveslevels or curves on images… on images… less data loss.less data loss.


Tip: Don't upsample unless using as a Tip: Don't upsample unless using as a method of doubling your scanner's line art method of doubling your scanner's line art resolution. Interpolation adds data, but resolution. Interpolation adds data, but not detail (information), resulting in soft or not detail (information), resulting in soft or blurry images.blurry images.


Tip: Lose noise introduced by the scanner Tip: Lose noise introduced by the scanner by scanning at the maximum optical by scanning at the maximum optical resolution, then downsampling to the resolution, then downsampling to the resolution you need. (Noise tends to resolution you need. (Noise tends to show up as single pixels. Downsampling show up as single pixels. Downsampling creates new pixels by averaging creates new pixels by averaging surrounding pixels, so noise is reduced surrounding pixels, so noise is reduced significantly.)significantly.)


Tip: Scan b&w line art in grayscale mode Tip: Scan b&w line art in grayscale mode then use various techniques (sharpening, then use various techniques (sharpening, thresholding) to massage the image. thresholding) to massage the image. Finally, convert the image mode back to Finally, convert the image mode back to b&w.b&w.


Tip: When rescreening a screen (scanning Tip: When rescreening a screen (scanning a halftone image), scan at high resolution, a halftone image), scan at high resolution, downsample using Bicubic Interpolation, downsample using Bicubic Interpolation, print at smaller size than original. print at smaller size than original.

scanning 101 and beyond media & instructional technology services darryl simcoe, instructor...

Documents

film negatives scanner

right scanner

reflective artwork slide

photographic film slide

depth slide

photographic film scanning

transparency available

transparencies transparencies