Scanning
Image Size and Resolution
Transform Effects


 

SCANNING INTO PHOTOSHOP

 

Unless youre using a digital camera, youre going to be scanning photographs into PhotoShop. Even if you are using a digital camera, clients will give you pictures to scan. So, youll need a scanner, and youll need to know how to effectively scan.

 

What kind of scanner do I need?

You dont need any kind of super expensive scanner for web work. Top end scanners are made for high-resolution print work. You dont want the bottom of the line junky scanner, either. Hewlett Packard makes very good scanners, the least expensive of which is about $100.00.

 

Make sure that you buy a flatbed scanner, and that it comes with Optical Character Recognition (OCR) software. OCR software "reads" scanned text, placing it into an editable text file you can use for your website. OCR comes in mighty handy the first time a client hands you twenty pages of printed material and says "put this in my website".

 

Setting Up PhotoShop To Recognize your Scanner

PhotoShop will not automatically recognize your scanner. Even if PhotoShop did recognize your scanner, it might not know how to talk to it. Lots of scanners are different. What you need is a program to manage the data coming from your scanner going into PhotoShop. That program is called a Data Source Manager, and happily enough, PhotoShop comes with one.

The industry standard data source manager for scanners is called TWAIN. The name "TWAIN" comes from the phrase "Ne'er the twain shall meet".

The data source manager transfers data between your scanner and your program (PhotoShop) so that they dont have to talk to each other.

 

Steps for Setting Up PhotoShop To Recognize your Scanner:

  1. Install your scanner and all of the software that came with it.
    (PhotoShop will still use your scanners software.)
  2. In PhotoShop, click FILE-> IMPORT-> SELECT TWAIN_32 SOURCE

 

PhotoShop will find all scanners you have hooked up to your computer.

 

 

  1. Choose your scanner and click SELECT.

 

Now youre ready to scan into PhotoShop!

 

Scanning into PhotoShop

From now on, youll scan images directly into PhotoShop.

To scan:

  1. Click FILE-> IMPORT-> TWAIN_32
    PhotoShop will find your scanner and open your scanners scanning software. You will use the scanning software as normal, but the final image will appear in PhotoShop.

 

If you can't import using the TWAIN interface, use your scanner manufacturer's software to scan your images, and save the images as TIFF, PICT, or BMP files. TIFF, PICT, and BMP are all "lossless" formats, which means that they save images without a loss of data normally associated with compression. After youve scanned, then open the files in PhotoShop.

 

Scanner Settings

Every scanner and the software that comes with it is unique, but they all share common settings. Because of this, we can't teach about every scanner in this web design course. You may have to read your manual (ugh) or click Help in your scanning software if you cant find the proper setting.

 

Scanning Modes

Most scanners have different modes for scanning. The scanner will scan differently depending on what it thinks youre scanning. Many scanners today will attempt to automatically detect what kind of image youre scanning, but you may have to manually correct the scanner if it makes a mistake.

 

Modes:

�.       Line Art: for black and white solid color drawings, like logos or pen drawings. Line art only reads pure black and white.

�.       Halftone: for anything printed with tiny dots, like newspapers, magazines, or something printed on a desktop printer.

�.       Color: For color photographs

�.       Grayscale: For black and white photographs.

�.       Text/OCR: For text destined for a word processor. Should not be used with PhotoShop.

 

Resolution

Your scanner will allow you to scan at different resolutions. When your images are published to the web, they will be 72 dpi. You may get very good results by scanning directly at 72 dpi.

 

Down sampling

You will often get better images by scanning at a higher resolution, and using PhotoShop to down-sample your work to 72dpi. Curves will often look smoother, and color will often be more natural. 300 dpi is often a good starting point.

Different images and different scanners react differently to down-sampling. Scanning at 72 DPI may work just fine for you.

To down-sample an image to 72 dpi:

  1. Scan image into PhotoShop at a higher resolution
  2. In PhotoShop, click IMAGE-> IMAGE SIZE
  3. Leave the check in Resample Image
  4. Change the resolution to 72

Your final image will be the same size as your original scanned artwork.

 

Use Higher Resolution Images for Editing

Often, when you down sample an image, editing mistakes that you made will be hidden! When there is editing or retouching to be done, it is a good idea to do it on a higher resolution image. Then, follow the above instructions to down sample.

 

Youll need a pretty fast computer with lots of RAM to edit those high-resolution images, though

 

Preview Mode

Most scanners have a preview mode that scans a low-resolution image first, allowing you to see and adjust what youre going to scan. Some scanners will automatically scan in preview mode if you set the resolution high.

 

Using Your Scanner To Enlarge Images

If youre going to enlarge an image, youre better off enlarging with your scanner instead of in PhotoShop. PhotoShop, when enlarging, adds pixels based on a mathematical algorithm. When your scanner enlarges an image, it actually scans at a higher dpi, and then spreads out the original pixels to meet your target resolution. Because all of the pixels are original, your scans will look better.

 

Use Enlarged Images for Editing

When you downsize an image mistakes that you made will often be hidden! When there is editing or retouching to be done, I often

 

Using Your Scanner to Counterfeit Money

You can use your scanner to counterfeit money by following the subsequent steps:

  1. Scan money
  2. Print money
  3. Spend money
  4. Go to jail

Continue to Image Size and Resolution |