With Photoshop open, click on File heading at the top left of the menu bar and select Open. You will be directed to the most recent location of images or folders last used to open a file. Navigate to the folder location or image you wish to open. If files are arranged in a list format, you can change to thumbnail view to see a mini version of each image. Make your selection and click on the Open button.
Since we have already covered the way we make file size and resolution changes, we can get to the heart of what this lesson is about: keeping image integrity. You can take a good picture, but if it loses it's detail or clarity, it's lost lot of the reason you like the picture.
The JPG file format in and of itself is a falsehood. In that I mean, it uses image compression so if you save the file , make a change, save it again, change the size, save it again and so on, you start to break down subtleties in the gentle changes of the sky or flesh tones... in other words, you throw information away.
A way to combat against that issue is to make as few drastic changes as possible. Only change the size and then save the image. If you are going to do massive work, it is better to use a non-compression format such as the TIFF format.
Ok, let's get to the root of the lesson. You want to make an image smaller in physical size, but not loose a bit of mb quality... no file size change, just image size. Well, that is pretty easy and you have already learned how... yes, the Resample Image check box. By unchecking this box, the measurements and resolution are locked together.
Adobe® Photoshop Class #3
In this lesson, we will learn about preserving file information integrity. There is nothing worse than realizing you have crippled your good picture by throwing away information. The elements we have already learned will be used to build yet another aspect of understanding. Let's recap a bit...
When you are done, make sure you choose the Save As menu to save your image with a new name. If you do not do this, you can ruin your original image quality.
Just to insure that you have this concept fully understood, the animation at left illustrates just how what you are doing... a see-saw of sorts. By showing you this, it might help cement the concept.
By changing the image size or by pushing down on the image dimensions, the resolution grows. By changing the resolution or by pushing down on the resolution, the image dimensions grow.
I hope this information has helped you understand this important concept. By keeping this in mind, you will avoid loosing your valuable photos.
See you in the next lesson....
So, in the two menus below, you can see that by unchecking the Resample Image box on the left, the Pixel Dimensions or file size remains the same even though the width of the mage went from 9.65"3 to 6" in the menu on the right.
Notice the three-linked brace on the right of the Width, Height, and Resolution info boxes. This indicates they are locked together. By doing this one thing, you preserve the Pixel Dimension quality of your original image.
Also remember, that if you actually want to reduce the size of the image for email attachments, you should keep the Resample Image check box on. This way, you reduce the file size while reducing the image size.
This is an example of how the file
details change when the resolution
and image sizes are locked together.
In this manner, the image file size in mb remains the same and thus the image quality never varies.
