Saving Your Image Files
Even though you started out with a JPEG image, if you try to save your photo after making all those changes, chances are that Photoshop will automatically save it as a Photoshop file (.psd) instead of a JPEG. Now that's all fine and dandy if you're just wanting to look at them on your computer, but you're going to cause a lot of consternation if you put a Photoshop file on your webpage. Most people don't have Photoshop, and .psd files are HUGE. There's really no need to even hang onto the .psd version of your adjusted image file anyway, since you smartly made a hard copy of your original JPEGs on a CD or DVD. If you decide you don't like the new changes, you can always go back to the original JPEG and start over. But let's say that you ARE happy with your changes, and you're ready to save a copy of the new image file for your portfolio website.
Saving As a JPEG
From the File menu, select "Save As". You'll get a window like this:

Use the Format menu (circled in red) to select JPEG, then double-check your file name at the very top of the window. Don't do anything else - just ignore all the check-boxes under the Format menu. Be sure that you're saving it in the right folder so you can easily find it later. Then click the Save button. You'll be presented with the JPEG options window:

If you're saving for your webpage, you can set the quality from 7 to 10 - it's very hard to tell the difference between 10 and 12, so you might as well save some space. You can watch how the size of your file changes between the different quality settings in the bottom "Size" section. Leave the Format Options as they are. Then click "OK" and you're done! Now you know how to shoot, save, resize and edit your documentation photos so that they can be the most accurate depiction of the object being documented and the best format for your web portfolio.
