Resizing and Sharpening Images - Advanced Beginner Level
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This tutorial focuses in on resizing your images using the Resize command.
You should already know how to open a new image, save the image, add a new raster layer, and rename
a layer.
If you do not know how to do this, refer to the tutorial, Introduction to
Layers and Opacity.
This tutorial has a few things that may be a bit difficult to comprehend.
If you have a problem understanding a concept, feel free to send us an
email or post a message on the bulletin board.
Also, know that you don't always have to understand everything in order to do what you want to do.
I used Paint Shop Pro 9 for this tutorial, however, you should be able to use other versions as
well.
For a free trial or to purchase Paint Shop Pro, click on the above link.
Step 1
Before we start, I must explain that resizing an image causes some distortion.
When resizing smaller, and done properly, and adjusted after the resizing, you will hardly notice
any change.
When enlarging, you will notice more distortion.
If you don't enlarge too much, it should be fine.
If you enlarge by a lot, the pixels become very distorted and blurry.
This tutorial is geared toward making smaller.
Another thing I want to mention is the Undo function.
This is great when you don't like what you just did.
You can undo something by clicking on the Undo Icon in your toolbar found below your file menu near
the top (see below, it's circled in red):
You can also use the file commands: Edit, Undo (Paste New Layer).
Open an image you already have.
It is best to use a photo for at least the first part of this tutorial.
So you don't accidentally overwrite your image, make a duplicate of it.
To do this, while your image is active, use Shift-D, or menu command Window, Duplicate.
A copy of the image will come up. You may close the original.
Step 2
Now we will resize the image.
You can either choose the file command Image, Resize or use Shift-S.
In either case, a window will pop up for you to enter your resize options.
The numbers may look a bit different, but don't worry.
Below is an explanation of the different settings:
Original Dimensions, see the red arrow, tell you your current image information.
Width and Height are shown in pixels and inches.
The resolution is also shown.
Pixel Dimensions, see the yellow arrow, tell you what will change when you click on
the OK button.
Above it states 100%x100%, then below it states 432 width and 324.
You'll notice that "pixels" is shown in the window next to it.
This can also be changed to percent.
If you changed it to percent, in this case it would read the opposite (percentage and pixels would be
reversed) as shown below:
The numbers can be changed to the size you want either by pixels or percent.
Just change the drop down menu to the way you want to resize.
You'll also be able to resize by inches, which we'll discuss next.
Print Size, see the blue arrow, will allow you to see or change the print size of
your image.
This section can be a bit confusing, because it also includes the resolution (pixels per inch)
section (which can be changed to pixels per centimeter if you prefer.)
I will attempt to explain this, but it is difficult for some people to grasp.
Pixels per inch mean just what it says.
If you have 72 pixels per inch, in one inch you'll have 72 pixels.
If you have 300 pixels per inch, in one inch you'll have 300 pixels.
The pixels in an image with 72 pixels per inch will be much larger than those in an image with 300
pixels per inch.
The 300 pixel per inch image would have much better clarity when printing.
It would also be a smaller print size.
For example, an image at 72 pixels per inch that is 300 pixels wide would be about 4.2 inches
wide when printed (200/72.)
The same image at 300 pixels per inch (still 300 pixels wide) would be 1 inches wide when printed.
They are both the same amount of pixels wide, but because the 300 pixel per inch image has smaller
pixels, it would print smaller.
This is an important thing to keep in mind if you ever change the resolution of an image.
If your camera's resolution is 72 dpi (dots per inch), but you put it in a scrapbook image you
are working on set to 300 dpi, the print size will be smaller.
So keep that in mind, too.
If you change either the print size (in inches) or the resolution, it will automatically
change the pixels or percentage in the pixel dimensions section.
Resample using, see the pink arrow, will give you several options for how
your picture is resized.
I've found that for most images, using Smart Size typically gives the best results.
In any event, you can always undo and try another to see.
Below are some comments on each of your choices:
- Weighted Average uses a weighted-average of the neighboring pixels to determine how newly
created pixels will appear.
This type is best for reducing for irregular or complex images.
- Bilinear uses the two nearest pixels to determine how newly created pixels will appear.
- Bicubic minimizes jaggedness and is generally used enlarging irregular or complex images.
- Pixel Resize duplicates or removes pixels to achieve the selected width and height
and is typically used on images with hard-edges and simple graphics.
- Smart Size computes all sorts of stuff to come up with what seems best.
I've found that this is typically best for photos.
Right under Resample using is Maintain original print size and should be checked
when you want the print size unchanged.
Lock aspect ratio, see the green arrow, should be checked if you don't want
your proportions distorted.
You may also change the proportion ratio to whatever you want.
Right under Lock aspect ratio is Resize all layers.
Check this box to resize all layers.
Right now make sure it is checked.
We'll get into resizing one layer a bit later.
Since I don't know what size your file is or anything else about it, you'll just have to enter
in your own numbers.
Changing the resolution for your first attempt probably isn't a good idea, though.
For those who can't decide, I'll suggest making your image 50% smaller (see Pixel Dimensions,
yellow arrow.)
Use Smart Size for Resample using (pink arrow.)
Name and save your file.
Step 3
You'll probably notice some distortion with decreasing it by 50%.
Now we'll go over how we can clean that up a bit.
You can use the "Sharpen" function, which is the easiest, by using the menu command, Adjust,
Sharpness, Sharpen (or Sharpen More.)
For some images, this works fine.
Others it causes some stray "noise" in the graphic.
Go ahead and try it and undo if you don't like the look.
For photos I prefer using the "Unsharp Mask" function.
Do this by using the menu command, Adjust, Sharpness, Unsharp Mask.
A window will pop up that looks similar to this:
Radius refers to the number of pixels that are adjusted around the edges.
Strength refers to the amount of contrast to the pixels.
Clipping refers to the difference in the lightness value that adjacent pixels must have
before they are sharpened.
You must realize that using the Sharpen and Unsharp Mask functions will only be
applied to the active layer.
You'll be able to see the difference on part of the image in the windows.
The image on the left is the current look, the image on the right is if you apply the changes.
Notice the "eye" icon (blue arrow.)
Clicking this will allow you to preview the changes on the image.
Click ok when you see what you like.
This can all be very confusing, so start with the default (shown in the picture above)
and adjust as you feel necessary.
I find it a more precise way to sharpen after resizing.
Step 4
Let's say that you've got a picture you've added to a separate layer.
You've decided that it's too big and want to make is smaller without making the
background or other layers smaller.
That's when you uncheck the "Resize all layers" box.
It will proportionally change just the active layer.
Sometimes it takes a bit of practice to get it right, because it does do it
proportionally to the whole image size.
But that's what undo is for!
You may sharpen the resized layer just as explained above, because it will only apply to the
active layer.
Assignment: Resize and sharpen a few graphics for practice.
This will help you get familiar with these functions.
Sometimes playing with it is the best way to understand.
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