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Thread: Images for The Glass Bead: Eye Candy, Critiques&Collections, Artist's Spotlight and More!

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    Join Date
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    Post Images for The Glass Bead: Eye Candy, Critiques&Collections, Artist's Spotlight and More!

    Hello ISGB members,
    from time to time I like to put out a reminder about how to best submit images for "print" in The Glass Bead, your membership publication.

    As you know, several of our members provide their knowledge, time and research in preparing the editorial content for our publication, and I would like to thank all of them—but in this in particular instance I'd like to call out, Jim Kervin for his Critiques&Collections article, Marcy Lamberson for her Artist's Spotlight article and Cindy McEwen for her Eye Candy cooridination.

    Preparing these articles take dedication and time on many levels. We do this to insure that our member's work is reproduced in its best possble light. After all, whatever we see in publications inspires us to take new directions and continue the learning process. And the print format is certain taken with more validaty. These days, it it's in print, it's practically set in concrete.

    So what do you do when someone asks you to submit a picture for a "printed" article and your can't tell a DPI between a DUI or a pixel betwee a pixy? Here is generalized formula. And, might want to check out this guide that is attached to this post.

    For print: Images are reproduced at 300 dots per inch ( DPI.)
    In an 8x10 images there are 2400 dots running width-wise. 3,000 running height-wise.
    8 inches x 300 dpi equals 2400 dpi width.
    10 inches x 300 dpi equals 3000 dpi width.
    Pixel wise the information will be 2400 x 3000 pixels

    For a large spread size image in a magazine, the image will often times need to be 17 inches wide. Wow, that's a lot of pixels—and a very large file size.
    17 inches x 300 equals 5100 pixels wide.
    Roughly that equals a 55 megabyte file. That's not going to travel through email. You need to upload and we'll get to that later.

    Now we'll go back to more manageable sizes for either our Eye Candy or Critiques&Collections articles.
    • A 9 x 12 (full page bleed) print size image is 2700 x 3600 pixels at 300 dpi. In RGB that roughly equates a 28 mb (megabyte) file.
    • An 8 x 10 print size image would be 2400 x 3000 pixels at 300 dpi.
    • A 5 x 7 print size image would have 1500 pixels x 2100 pixels at 300 dpi.
    • A 4 x 6 print size image is 1200 pixels x 1800 pixels at 300 dpi.
    • A 2 x 3 print size image is 600 pixels x 900 pixels at 300 dpi.

    Why 300 dpi? 300 dots per inch DPI is visually equivalent to most printing line screens, Lines Per Inch LPI. As a rule of thumb:
    133 lpi requires images at 266dpi (133 lpi x 2 = 266dpi)
    150 lpi requires images at 300dpi (150 lpi x 2 = 300dpi)
    Most magazines use a 150 lpi dot screen on their plates. Or if digitally printing the line screen is between 133 and 150, between 266 and 300 dpi.

    Newspaper line screen are generally still between 65 and 85 lines per inch. This is why you rarely see "sharp" images in the newspaper. A graphic artist will "resample the file to a specific" line screen. Or the newspaper pressman will electronically alter the file.
    http://dx.sheridan.com/advisor/line_screen.html

    Web equivalents are much different.
    8 x 10 image is 576 pixels wide x 720 in height at 72 dpi. Most laptop and desktop monitor reveal images at 72 to 96 dpi. We won't get into high-def video!

    So when you are in a picture editing software program, please make sure that your files are designated as 300 dpi to the actual print size the image will be.

    One VERY IMPORTANT THING! You can increase an images DPI slightly, but you can not simply take a 3 x 4 inch images at 72 DPI and increase it's resolution to 300 dpi. Yes, It is increased "measurement" wise, but you are simply taking what little information there is an spreading it more thinly. You've actually lost information. Think of spreading a teaspoon of jam over cracker, and then the same teaspoon of jam over a round flour tortilla. Less jam in each bite!

    The difference is sampling:
    RESAMPLING is changing the amount of image data as you change either the pixel dimensions or the resolution of an image. When you DOWNSAMPLE (decrease the number of pixels), information is deleted from the image. When you resample up (increase the number of pixels, or upsample), new pixels are added.
    KEEP IN MIND that while new pixels are added, you can not add information that does not already exist, you are simply adding pixels, not information or detail. In fact enlarging this way gives you blurry and "pixelated" images.

    You can take a large 72 dpi image and 'scale' or resample it proportionately to 300 dpi. For instance:
    A 2400 x 3000 pixel image at 72 dpi measuring 33 inches x 41 inches be "resized" or "resampled" to 300 dpi.
    The images is still 2400 x 3000 pixels, but when you change the 72 dpi to 300 dpi the image measurements become
    8 inches x 10 inches. They've been resampled.

    FILE Transfer
    Most email programs will attach a 10 megabyte file with no problem. But what happens if your file is bigger? Check out YouSendIt.com. You can register for free and send images across the WWW, via FTP with a few simple clicks.

    Many editors will give you an FTP url to upload to. It's a much faster way to deal with large files.

    There is much more information about RAW Camera Files and conversions to JPG and CMYK and TIFF files. But for now, this will get most everybody on the same "printed" page!

    Many thanks for reading.
    Diana
    Direcotor of Marketing ISGB
    Attached Files
    Last edited by LaMaridoLampwork; 04-25-2010 at 09:55 PM. Reason: clarification

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