Enlarging an image file
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Thread: Enlarging an image file

  1. #1
    JLS is offline Virtual PC Specialist!!!
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    Enlarging an image file

    Is there a way to enlarge an image file (eg. jpg, gif, etc.) without distorting the original image?

  2. #2
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    No.
    Enlargening will pixilate the graphic every time. Ruining it.

    Got the original, rescan it as 20 -40 MB tif.

  3. #3
    JLS is offline Virtual PC Specialist!!!
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    Hi, Train. I am not sure I understood your reply. Are you saying that were is not a way to enlarge an image without distorting the file? What did you mean by: "Got the original, rescan it as 20 -40 MB tif.", also?

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    Are you saying that were is not a way to enlarge an image without distorting the file?

    That is true.

    I have a scanner and when I run into a situation like you have, I just rescan the original at a much larger size. Usually in the 20 - 40MB file size in the tif format. I can always make it smaller later. But never larger.

  5. #5
    JLS is offline Virtual PC Specialist!!!
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    Ok, thanks. After you rescan the original to a .tif file (whatever a .tif file is), how is the quality of the image?

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    The quality of a scan depends on the quality of the scanner, the resolution at which the image is scanned, the quality and surface texture of the original being scanned, the size of the original being scanned, the cleanliness of the scanner glass and the abilities of the operator.

    The higher the resolution used to scan an original, the higher the likelihood that imperfections will become visible. But if you want to reproduce the original in a large format, you need more real data to start with (higher scan resolution). Unlike the various televisions programs where the picture is zoomed in on, "resolved" and zoomed in again to reveal the license plate of the car parked half a mile away from the ATM machine camera, real scans (or digital photos) cannot be made any larger without becoming jagged/fuzzy. Increasing the resolution after the scan or photo is taken by modifying it on a computer cannot add any new real data -- it can only fill in the gaps with a calculated halfway value from adjacent pixels. The image doesn't get any clearer, but it may not look as jagged.

    Similarly, scanning at a resolution higher than the rated optical resolution is just the computer creating filler bits. Taking a picture with a digital camera using "digital zoom" is just the camera's computer creating filler bits -- it's not real color values from the real world image.

    As for JPG versus TIFF, TIFF is a lossless format -- every bit scanned into the computer remains in the file that is saved. JPG is a lossy format -- it was developed specifically to save large full color photographic images with a user determined level of data loss in order to make smaller files (the user determines the acceptable trade off of space versus quality in ten steps). If you're going to do any editing work on an image, you want to have it in TIFF format as early as possible, and keep it that way until done. Each time you save a JPG image, it recalculates which bits are lost, and the next time you open the file there's no way to get those bits back.

  7. #7
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    photolady is offline Lifetime Friend of Site Staff
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    Just to add, size of photos/images come into play here also. You cannot resize any image over twice its original size without distortion/pixelation. Speaking of jpgs or gif images only. And mainly images acquired from the net, not your own scanned photos.

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