Saturday, October 24, 2009

A Beginner's Guide to Scanning Postcards

I was honored when Evelyn

1. What equipment should I use when scanning postcards?
A flatbed scanner that can scan at a 300 dots per inch (dpi) or greater resolution and can scan to the tagged image file (.tif) format is a must. Your computer should have photo editing software such as Adobe Photoshop, Corel Paint Shop Pro, or the many free types you can download from the Internet (do a Google search). Cotton gloves such as those found at your local photography supply store or online at archival supply websites are also vital for keeping your postcards from being microscopically damaged from the oils in your skin when handling.

2. On what settings should I put my scanner?
As mentioned above, you'll want to scan at no less than 300 dots per inch resolution. Many experts agree that 600 dpi is even better. This will enable you to zoom in and see details that your naked eye can miss, which is especially helpful for those postally used postcards with difficult-to-read postmarks! Also, it is imperative that you scan to a tagged image file (.tif) format (more on this later). All scanning should be done in full color, even for those photo postcards that are printed in black and white. The color will bring out the highlights and shadows that scanning in black and white and greyscale cannot do, and will also digitally preserve your postcard as it truly is viewed by the human eye: in color.

3. How do I prepare for scanning?
The glass plate of your scanner should never be cleaned by commercial glass cleaning products such as Windex, which may leave a chemical residue that can damage your postcards. Instead, use a soft lint-free cloth that has been sprayed with water to clean the glass plate of dust, oil, and streaks. Make sure the plate is completely dried before placing any postcard on its surface. I also like to tape a large piece of black construction paper to the inside of the white lid of my scanner, so that the edges of the postcard can easily be seen in the scanned image. Otherwise, the white edges of the postcard can seem to merge into the image of the white lid and it is difficult to tell exactly where they are when cropping the image.

Meanwhile, your postcards should be set up in scanning order on a nearby clean surface, free from any food, beverages, or other items that could damage them. Take the time to figure out exactly what you want to scan and in which order they will be scanned.

4. How should the postcards be scanned?
I scan four postcards at a time with spaces between them, being very careful not to slide them around on the glass (pick them up to move them). I then carefully flip each one over in its place and scan the reverse of the four as another image. This saves me time in scanning and room on my hard drive.

5. How do I save and use my scanned images?
Every image should be saved as a .tif file, which does not deteriorate over time with every use like .jpg files do. Jpg files are common photo file formats used to transport photos from one location (your hard drive, for example) to another (an online photo album, or an e-mail, for example). The problem here is that .jpg files are compressed for that easy transportation, and every time you save or use that file (e-mail it, download it, etc.), it loses some of its quality. Also, if you've ever zoomed in on a .jpg file, you'll notice that it quickly becomes blurry, whereas a .tif file can be enlarged multiple times in a zooming action before the resolution blurs.

When I make presentations about scanning and preservation, I like to do a little demonstration. I take a piece of blank paper and show it to my audience, saying, "This is my digital photo as a .jpg file." I then crumple the paper and toss it to a member of the audience and explain that because I crumpled (compressed) it, it made it easier for me to transport to someone else. Then I have the person smooth out the paper the best they can to look at it. Of course, now it's wrinkled. Then I have them crumple it again and toss it back to me. Each time the paper is used, it is crumpled and then unfolded. The quality deteriorates. The same thing happens at a digital level; the quality of the photograph in a .jpg file deteriorates every time it is accessed.

So even if your postcards are not photo postcards, they should still be saved as .tif files. This will digitally preserve the image. Any enhancements, cropping, color changes (color to black and white or greyscale, etc.) should be done to copies of the original .tif file. If you wish to e-mail a postcard image or upload it to a blog, do a "Save As" action and save the image as a .jpg (retaining the original .tif file, of course) and then send it out.

Lastly, I "separate" the images of the four postcards by copying each one four times and cropping them. I tag the images with information that will help me easily find them in a desktop search. These final two steps, separating and tagging are done after I've finished all my scanning.

6. What do I need to do when I'm finished scanning my postcards?
I recommend placing the postcards in an acid- and lignin-free storage container or enclosed display frame. Both Archival Products and Archival Suppliers offer postcard preservation supplies.

Never place them in "magnetic" photo albums or cheap photo display books. Don't store them with newspaper clippings, which are made of acidic paper. Also, don't store them with photographs, as the postcards may be made of acidic materials themselves and destroy the photographs stored with them. Acidic paper creates a gas that eats away at photographic materials.

Be sure to back up the scanned images to a DVD, flash drive, external hard drive, or the Internet. Have two different kinds of backups and store them in two places, one away from your home.

By following these tips, you can preserve, display, and share your wonderful postcard collection in a digital format. If you have further questions, leave them in the comments below. And be sure to join me and my family historian and family archivist friends for Scanfest, usually held the last Sunday of each month, here at AnceStories. There are a number of experts who would be glad to give scanning and preservation advice, and we have a lot of fun, too!
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