Resizing images in photoshop is a subject that a lot of people ask questions about. Resizing is very easy with the newer versions of Photoshop.

The correct way to resize an image is through the Image Size window. Go to the main menu then [Image->Image Size] a window with various settings will appear:

When resizing an image you need to determine whether you are enlarging it or reducing it’s size. Using the wrong settings for either can result in non-optimum image resizing.

1. Ensure that the “Constrain Proportions” settings is checked “on”

This will ensure that when you resize your image, it won’t get stretched in any way while resizing the image. If you want to change the image proportions, you can do this later using the crop tool or the canvas size window which I will mention later in this tutorial.

2. Ensure the “Resample Image” setting is checked “on”

When Resample Image is set to on your image actually changes size when you change the image dimensions under “Width” and “Height”. If you try to resize the image with the Resample Image unchecked the only thing that will change is the resolution.

A note on resolution: The resolution of an image can be changed without resampling the image. If you change the resolution without “Resample Image” setting on, all this will do is change the width and height of the image in inches (or whatever measurment you set it to). The images pixel count will remain exactly the same. When the Resample Image setting is on the images pixel count will change. I will illustrate this below.

As you can see, the “Resample Image” setting is important when you want to resize an image.

3. Decide if you want to “Scale Styles”

If you have an image with 1 layer, you can ignore this setting. The “Scale Styles” setting tells Photoshop whether to scale styles on layers. For example, you can put styles on layers, Stroke, Bevel, Drop Shadow, Etc.

If Scale Styles is on, strokes and drop shadows settings will increase appropriately to the new size. If you have a small image with a 1 point stroke and you scale it up, the stroke will get thicker in the correct proportion. If you resize the image with “Scale Styles” off the stroke will remain at 1 point no matter  how big or small you make the image.

The above image illustrates the use of the “Scale Styles” setting. As you can see, this setting is only important if your image has layer styles in it.

4. Set the correct scale setting

Choose from the dropdown a correct scale setting. I will list the settings and when they should be used:

Nearest Neigbor: Use this setting when sizing images with hard edges. Images with solid colors and sharp lines will best be resized with this setting. Do not use this setting for Photographs.

Bilinear: Some pictures can be upsampled pretty well with bilinear interpolation. But we usually use one of the bicubic options below instead.

Bicubic (Best for smooth gradients): Bicubic is the best for photographs and smooth colors. Photoshop gives you 3 different bicubic settings. I suggest using either of the 2 below for resizing your images unless you have a lot of smooth areas in your image with blurred adges.

Bicubic Smoother (best for enlargement): Use when enlargement of images, using this setting will produce the best for making images and photos larger because it smooths out the image a bit to produce better detail quality.

Bicubic Smoother (best for reduction): Use when reducing the size of images, using this setting will produce the best results for making images and photos smaller because it keeps the feeling of the original sharpness of the image.

5. Set the new size for your image and press OK

You can change the size of your image in numerous areas. You can change any of the numbers under “Pixel Dimensions” and any of the areas under “Document Size”. You can change any one of these settings to change the image dimensions. Now click OK and your image will be resized.

Image resizing Summary

1. Ensure that the “Constrain Proportions” settings is checked “on”
2. Ensure the “Resample Image” setting is checked “on”
3. Decide if you want to “Scale Styles”
4. Set the correct scale setting
5. Set the new size for your image and press OK

An additional Note: You can resize images in your Photoshop file by using the Free Transform tool, be sure to set the correct Image Interpolation setting by going to “General” in the Preferences Window and choosing the right setting as gone over under step 4 above. When resizing with the Free Transform tool hold down “Shift” to keep the image proportions the same (Prevent stretching the image).

Now that I have shown you how to properly resize an image in Photoshop I will show you how the Canvas Size window works, so you know the difference.

Canvas Size Window

The Canvas Size Window allows you to crop an image using the width and height dimensions.

The canvas size window is much simpler than the Image Size window.

First change the width and height to be larger or smaller.

Next set the anchor where you want it. If the anchor is in the center, the width or height will be added or removed equally around the image. If the anchor is on the right in the middle, any changes to the width will happen to the left of the image. You have 9 different anchor positions depending on what you want to do with the image.

Finally, pick a color in the Canvas extension color area. This will set a color to any area you add to the image (See example below)

Below is an example of using the Canvas Size window to alter the left side of an image.

This image shows the original image on the left. The image in the center shows area added to the image with the Canvas Size (Red area added). The image on the right shows the left side of the image cropped with the Canvas Size Window.

Canvas Resizing Summary

1. Change the width and/or height dimensions
2. Set the anchor where you want it
3. Pick a color in the Canvas extension color area
4. Press OK

This tutorial will give you an idea of how to productively clone an object out of an image.

Level: Intermediate (can be useful for advanced Photoshop users)

Photoshop Version: CS4 (Can apply to Earlier versions up to Photoshop 6)

Tutorial:

Select the eraser tool and select a brush with a very blurry edge.

Then merge both layers as shown below.

Select the Polygonal Lasso Tool.

Select the area around the petal and the leaf.

Feather the selection with a 15 pixel radius.

Level: Intermediate (can be useful for advanced users)

Description:

This is a tutorial on changing specific colors in an image using the color range tool in Photoshop.

You can use this tutorial to easily change regions of color in an image to different colors. This can be very useful if you want to make a part of an image fit into the color scheme of the background or even just changing the color of someones dress or a clothing item.

Photoshop Version: CS2 (Can apply to Earlier versions up to Photoshop 7)

Tutorial:

The first step here is to go to the menu [Select->Color Range].

Then click on the area of color in the image that you want to change. Here we are clicking on a red part of the women’s dress.

The end goal for this tutorial is to change the color of her dress.

You can use the plus and minus eyedropper buttons to add more regions of color to the selection. Here we are just using one sampling of red. Adjust the fuzziness. (The amount of similar colors to the one you clicked to add to the range. If you go higher it will select any kind of red, if you go lower, it will only select a ceartain amount of reds similar the the area of her dress that you clicked)

Click ok to see the selected area of the image. As you can see here, we selected her dress but her lips are close to the same color so they were selected as well. The next step shows you how to remove those areas that you want to leave alone.

Click on the “Edit in quick mask mode button on the toolbox. This will bring you into the “Quick Mask” mode which will allow you to edit the selection by using the brush tool.

All of the areas that are pink are the areas that are not selected. Select the brush tool and make sure your foreground color is black. Paint out the area around her lips and head. This will remove the selection from those areas.

Once you have done this, click the “edit in standard mode” in the toolbox. This will return you to standard mode where you can see the dancing ants around what is selected. You will notice that the area that you painted out is no longer selected.

Now you can do whatever you want with her dress because you now have it selected. Here I show you how to change her dress color from red to purple. Go to the Menu [Image->Adjustments->Hue/Saturation] and set the settings shown here. You can also experiment with the sliders to see what colors you can get.

Here is the finished dress showing the color has been changed.

Level: Intermediate (useful for advanced users)

Description:

This is a tutorial on how to minimize printing anomalies like banding and odd color variations. Incidentaly, this tutorial covers some photo correction technique which can be very usefull for adding detail back to images.

Photoshop Version: CS2 (Can apply to Earlier versions up to Photoshop 7)

Tutorial:

I have come upon a technique for reducing printer anomalies (Banding, color patches and ghosting) that is really quite simple.

When I say “banding” I mean where you visibly see color changes in a gradient or image as you can see here:

When I say “ghosting” I mean areas of light color around dark color areas which shows up when printing but not on screen. An example is shown here:

The main technique is to add enough noise. Adding noise to a gradient will reduce printer banding. This is also true for areas of solid color — adding a bit of noise can make the color print very even.

When it comes to photos, this technique can be used to give the appearance of detail. I use this after I have resized and color corrected a photo. It is amazing how effective it is in making the print a much nicer print.

Realize when I am talking about printing here, I am specifically referring to large format printers. The technique can be used successfully with other printers as well.

When you add noise, you want to add just enough to where it is just past visible. I will show you some examples here:

Noise added to a gradient:

Noise added to a patch of color:

Noise added to an image:

Additionally you can reduce ghosting by adding noise. Ghosting is where you can see lighter areas around dark patches. An example of adding noise to an image that might ghost when printed is here:

Experiment with your printer and different noise settings to see what comes out the best.

I have found this technique to be very helpful on my job as a designer. Hopefully this tutorial will help you as well.