Why are my imported pictures fuzzy or blurry?

Question

Recently, some of our images that look good in Preview and Adobe Photoshop look fuzzy or blurry when imported into a layout program (like QuarkXpress) or a word processing program (like MS Word and Bean).  The affected pictures only seem to be those that we’ve reduced the image size on (from about 30”-40” to 2”-3”) and changed the resolution (from 72 ppi to 300 ppi).  We have followed this same procedure with the same hardware and software for years with no problems. Now they’re blurred.
They look better when printed (compared to on screen) but they are still not the quality we have had in the past.
We have tried the following:
- We found the same results with the same pictures on multiple Macs (and multiple operating systems).
- We tried using a TIFF instead of a JPEG, but it didn’t seem to make a difference.
- We reinstalled our QuarkXpress (this was before we realized the problem was also in other programs, like MS Word)
- We tried reducing the image size in Photoshop rather than Preview
Any suggestions?

Answer 1

I can't explain what has changed in Adobe Photoshop, QuarkXpress, MS-Word, or Bean because I don't use any of those programs on the Mac platform.
In any case, I can easily explain why your small images look blurred:
Resizing them so drastically smaller, you discard about 70% of the original image resolution by going from 30"x40" at 72dpi to 2"x3" at 300 dpi.
Your original images:
30" x 72 dpi = 2160 pixels
40" x 72 dpi = 2880 pixels
Your converted images:
2" at 300 dpi = 600 pixels 27.7% of the original pixels, a 72.3% loss of "detail"
3" at 300 dpi = 900 pixels 31.5% of the original pixels, a 68.5% loss of "detail"
Some possible work-arounds (using doubles and halves):
1) If you want the same apparent resolution at 300 dpi, you need to make the 300 dpi images larger:
Divide original pixels by 300 (dpi) to get an equivalent size at 300 dpi, but now images are over 3 times larger than your 2" x 3" size requirement.
2160/300 = 7.2"
2880/300 = 9.6"
2) Divide by 600 dpi, and we're closer, but still about double your size requirement.
2160/600 = 3.6"
2880/600 = 4.8
3) If you want the same apparent resolution near the size 2" x 3", increase the resolution to 1200 dpi
Divide by 1200dpi, and we're just under your 2" x 3", but these images still retain detail when viewed just slightly larger.
2160/1200 = 1.8"
2880/1200 = 2.4"
Another alternative that sacrifices some quality. but not as much:
If you want to compromise quality a bit and still use the 2" x 3" image size, try 600 dpi. It won't be as sharp as the original, but might be an acceptable compromise because you're keeping more than half of the original resolution. It depends quite a bit upon the subject matter. Intricate landscapes usually look better at lower resolution than dramatic headshots where the loss of those intermediate shades makes pixelization so obvious.
2" x 600 dpi = 1200 pixels, 45% loss, 55% of original
3" x 600 dpi = 1800 pixels 37.5% loss, 62.5% of original
And finally if you simply must have BOTH 2" x 3" and original resolution, here are the exact numbers:
2160/2" = 1080 dpi
2880/3" = 960 dpi
This discussion does not speak to the file sizes of the resized images, nor the maximum output resolution capabilities of your viewing and printing devices.