Digital Projection - Resizing Images for the Club Projector

Over the past couple of months we have had several club members who had difficulty resizing their images for competition, so I thought that it was time again to provide a summary of why and how to resize images.

The "why" is pretty simple. PowerPoint is the application that we use for competition judging projects slides at 1024x768 pixels, which is the maximum native resolution of our projector. If your image is not the correct size, then it will be scaled by PowerPoint to fit the projector resolution. PowerPoint uses a fast scaling algorithm, which is excellent for presentations, but can ruin a projected photograph. During the scaling process, it is possible to loose shadow detail and sharpness, so unless you are projecting an abstract with a soft focus or little detail, your photograph will probably suffer significantly and be rejected by the judge. At the very least it will not be a very accurate depiction of what you intended to show.

There are numerous ways in which club members use to resize their images, but I will describe the most common that I have seen. The first is simply setting the image size, the second is by using the crop tool. Both methods can yield an image that is within the limits of competition and either may work for you.

First, regardless of which method that you use, you should start with the best copy of the image that you have. I typically save my processed RAW images as TIFF files, either at full capture resolution or cropped minimally to make the horizon level. My TIFF master file is where I always start this process.

To resize an image using Photoshop's Image Size function:

Open the image.

Select Image, Image Size...

A dialog will open showing the current image size.

If you are resizing a landscape format image, simply set the Width to 1024.

If you are resizing a portrait format image, simply set the Height to 768.

Make sure that Bicubic is the selected resampling method. If you prefer not to handle resizing and sharpening as separate functions, you can choose Bicubic Sharper, which will automatically apply sharpening to the resized image.

Press the OK button.

To resize an image using the crop tool:

Select the Crop Tool.

Set the image size constraints:

For a portrait format image with an arbitrary width, put 768 in the Height field and leave the Width field blank.

Click and hold in one corner and then drag toward the opposite corner. You can adjust the size and placement of the "box" containing the image that will be displayed.

Press the Enter key to complete the crop.

With both methods, the image generally still needs to be sharpened. Sharpening helps to increase the amount of contrast, but can create "halos" if applied too generously.

If you are using an application other than Photoshop to resize your images and you are having difficulty, please feel free to email or call me.

Matthew G. Schmidt

703.975.6342

mgs@loreleistudios.com