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Old Dec 27, 2002, 5:59 PM   #1
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Default Cropping

I use a Olympus c-2020 which is a 2 meg camera. I take pics at 1600x1200 and send them out for 4x6 prints. Very nice results.

If I crop a picture to remove some background down to say 1200x900, what will happen to the quality of the print? Does a 1200x900 print at the same quality for a 4x6 picture as a 1600x1200? Whats the correct "number" to go by? Is it the 1600x1200 or the Pixels per inch? Thanks very much.

Tom
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Old Jan 2, 2003, 8:46 PM   #2
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Default comment on cropping

If you are using photoshop you have to set the resolution of the crop and if you set it to the resolution that your image is (DPI)
your crop will be the same quality as your origional image.

I ran into this very problem, until I realized once I clicked on the cropping tool, I had to set the resolution of the area I was to crop.

good Luck!

Jim
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Old Mar 19, 2003, 11:00 PM   #3
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I believe the correct resolution is 1600x1067. I got that number buy solving it as a ratio algebraicly. How you would use the number is for you to figure out. In Paint Shop Pro 8.0 Beta, I just resize the image to 6x4.5 without resampling, then crop off the extra half inch.

Oh and you used the correct term (PPI) Pixels per inch is used on digital images, DPI (Dots per Inch) is used on the printer. A dot is round, not square, which is why we use the term pixel instead. If you really want to know, pixel is an abbreviation for two words, "Picture Element"
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Old Apr 6, 2003, 5:40 PM   #4
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Ah, I have found a better way!

On PSP 8, I can tell it to maintain a print size (on the crop tool), and put 4 and 6 in the dimension boxes. Then it draws a crop box on the image which I can move and resize any way I want. When I'm done, I just double click and poof! A perfectly cropped image!

This way, there is no need for resizing and guessing. Very cool.
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Old Apr 7, 2003, 4:35 PM   #5
lg
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That's an interesting trick, Melboz99! I had tried out a much earlier version of PSP (v4.?), but decided I didn't need all the extra bells and whistles. Perhaps I'll check it out again...thanks for that little tidbit of information...
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Old May 11, 2003, 8:57 PM   #6
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If you crop a picture to half of its original size, you throw away half of the pixels and half of the data. Setting the crop area to 4 X 6 simply forces the ratio of length to width to that ratio.

You can easily render a picture file too small to print a good quality output. There are a couple of ways to minimize the problem...

1. Don't crop... not a great alternative. Cropping is a powerful tool to eliminate stuff from the picture you don't want to print. Smart use of a zoom lens and judicious framing of the subject (a real art) helps. My Canon Powershot Pro90 has a 10X zoom. Proper framing of the subject minimizes the requirement to crop pix, even at "only" 2.6 megapixels.

2. Use a camera that has enough resolution to to let you throw away the part of the picture you don't want and still have enough left data to print an acceptable picture of the size you want. Cropping down a photo by 50% from a 5MP camera will obviously leave more data than one from a 2MP camera cropped to the same level.

3. Upsample... this option lets you interpolate (or add) pixels to make up for those you cropped out, or add enough to print a larger picture than you could without the extra pixels. Many editors (Photoshop, etc.) offer upsampling. Genuine Fractals is a popular plug-in that does the same thing in a very elegant way. Upsampled pictures sometimes lack the "punch" of those that aren't. Upsampling is a trade-off. It lets me print larger pictures than I could normally expect to print... works fine, but maybe not as high quality as an optically zoomed one taken with a higher megapixel camera.
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Old May 15, 2003, 10:58 AM   #7
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Does PSP 7 do the same thing as PSP 8 that melboz99 mentioned?
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