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Cropping photos

Android phones, iPhones and photo apps allow you to change the photo size, resolution and aspect ratio. So, if you’re using your phone as your main camera you can use the phone’s photo settings for various sizes, resolutions, aspect ratios including:

But most digital single lens reflex (DSLR), 35mm film, and mirrorless cameras capture at a set 3:2 (Canon & Nikon) or 4:3 (Olympus) aspect ratio, which don’t fit exactly into an 8 x 10 format without some loss of picture during cropping. Trying to crop photos can sometimes be an exercise in annoyance.

A 3:2 camera’s images can be sized evenly to

  • 3 x 2
  • 4 x 6 (or 6 x 4)
  • 6 x 9 (or 9 x 6)
  • 8 x 12 (or 12 x 8)

But if you crop to match other common photo sizes, you’ll run into problems.

Here is my granddaughter looking angelic for her Christmas portrait. This was shot with a Canon DSLR, which uses a 3:2 ratio. If cropped to 8×10 it would lose most of the mantel – not acceptable.

The 5×7 result is better for this photo – it trimmed out some excess floor and kept the mantle.

If the photo is a head shot, or if you want to change from a vertical (portrait) to a horizontal or wide (landscape) format, cropping problems can be even more extreme. Here it lost most of the hat she got for Christmas and it lopped off her chin:

Cropping to 8×10 wide is only a little better:

But it still loses a lot of the image.

So how do we fix this problem? It’s best to make adjustments before you take the shot:

  • Set your camera to the highest possible image size – 5mg or more
  • When shooting the photo, pull back from the subject a little, so that there is extra material in the image that can be cropped out.

Once the shot is in the camera there may not be much that can be done, but there are a few possible fixes:

With the Crop Tool in Photoshop or other photo editors

  • When editing the photo, use the crop tool and pay attention to what is being left out.
  • Move the cropping box to include as much as possible.

With the Resize routine

  • Check the “Constrain Proportions” box
  • Set the longest side measurement to a little less than the paper size

With the printer:

  • Many printers have preset photo sizes, choose one that suits your photo
  • Uncheck the “Fit picture to frame” box, if your printer has this.

Here I’m printing a full 8×10 photo and I don’t want the printer to expand the photo to 8.5×11 inches because that usually creates strange borders or “bleeds” (the photo goes off the page.)

Some day printers that accept actual photo paper sizes will be available for home and small business use. Until then, we will have to make adjustments if we want to print our own photo.

There are several charts and calculators on the web to help us make those adjustments. For example, here is a chart from Design215.com – http://www.design215.com/toolbox/megapixels.php

*Typical Resolution. Actual pixel dimensions vary from camera to camera.
**At 150ppi, printed images will have visible pixels and details will look “fuzzy”.

More resources on the web:

PhotoKaboom.com: Printing Calculators http://www.photokaboom.com/photography/learn/printing/1_calculators.htm#Print

Print Crop Tool – now has a calculator for Android
http://www.camerahacker.com/Techniques/Print_Crop_Tool/Java.shtml

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