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General procedure (Photoshop)
Example of re-sizing process to reach under 300KB from Photoshop (the process is similar in other tools):
- Open your file.
- Image > Image Size. Set the longer dimension to 1200 pixels (maximum) and resolution to 72 or 96 pixels/inch.
- File > Save for Web Option
- Verify file size (or set to under 300KByte)
- Save as a jpg type file
Detailed procedure (PS Elements)
The following procedure shows a typical resizing workflow in Photoshop Elements 6. Thanks to member Aqualung (Chris Wraight) for providing the procedure and images.
1. This is the initial crop. Note that the resolution is set to 96dpi (72 is probably fine).
2. This is after editing (color correcting, etc, but not sharpening). Select Image | Resize | Image Size. For posting in Nikonians forums, set longest edge to 1200 pixels (not 800 as shown in the illustration). Then sharpen as the last step before saving.
3. This is in the File | Save for Web step, after clicking on the '=>' and then you will select the Optimize to File Size that pops up.
4. This the dialog that pops up after step 3. Set the maximum file size and it will automatically adjust the quality. Also in the lower right, you can see that it's also possible to set the maximum pixel length here after you choose the optimised size. Remember though, that this method will strip EXIF data from the picture.
5. At this point, choose File | Save As and after you've specified the location & filename, you'll see this dialog. Typically choose a quality value of '4'. Note that the reported file size under the 'Preview' is usually about 25-30k larger than the actual saved file.