"I don't know how to shrink an image!"

Your camera takes really BIG pictures, but you don't know how to shrink them, right? Do you just email them as-is to everyone? Did you know that that can create problems for them, like much longer download times or a full email box that doesn't let other's emails come in? Oops! These instructions are for you! :)


Download and install Irfanview. It's free.
  1. Open (view) the image in Irfanview
  2. Crop the image (to trim off uninteresting stuff at the sides or top or bottom)
    1. Imagine a "just right" rectangle around the portion that you wish to keep.
    2. Move your cursor to the upper left corner of that imaginary rectangle.
    3. Click-hold your left mouse button at that upper left corner, and drag down to the lower right corner.
    4. Release the mouse button when you like the shape of the visible rectangle.
    5. Crop it with menu Edit > Crop Selection
  3. Shrink the image to be no greater than, say, 700 pixels:
    1. Menu Image > Resize/Resample
    2. Click the "Set new size" circle.
    3. Replace the largest of the two numbers with 700.
    4. Click OK
  4. Save the image with a 75% quality
    1. Menu File > Save
    2. Note that there are two windows: one for the name of the file, and one for the "JPEG/GIF save options"
    3. Move the slide bar in the "JPEG/GIF save options" to 75 (if it is not already there)
    4. Provide a new name in the "File name" box (if you want to preserve your original photo in its original state) and click Save.

With this approach, your images will nearly always end up smaller than 70 KB in filesize.

Terminology

When people make mistakes in shrinking images, it may be because they aren't aware that "size" involves three separate concepts:

  • the resolution of the picture in dots per inch (how many dots of the image can fit within an inch, or "dpi")
  • I recommend 72 dpi.

  • the width/height (or dimensions) of the picture on the screen (typically measured in "pixels" or dots or points)
  • I recommend no greater than 800x600, typically (and often it is better to have something much smaller, if the details are obvious in the picture).

  • the quality setting that is typically offerered at the moment the picture is being saved in JPG format
  • I recommend a Quality (watch for such a choice while saving the picture in JPG format) about 75-80% of the highest setting. Depending on the software, the Quality value might be called 75% or "8" (out of 10) or "High" (lower than "Maximum").

    The most common mistake I have seen is reducing only the Quality when saving the file and leaving the dimensions (width/height) alone (for example, 1024x800 or 2200x 1600). The result is a really "grainy" or "chunky" looking picture.

If you can find how to change these three items in your photo software, you should be on your way to good photo sizes. Don't forget to keep a copy of the original: see "Preserving the original picture."

If you cannot figure out how to change the resolution, dimensions and quality of a picture with your photo software, consider using IrfanView, an excellent, free photo program that can do far more than I describe here.