Posting photographs

Posting a photograph to the UKTC

The UKTC allows you to send photographs and other images to the list. However, there is a limit imposed on the size of message sent to the list, so some care is often needed to get images within this limit.

The maximum size of message that can be sent is 250kB. This is the size of the entire email. By the time you have allowed for some descriptive text, the email headers and the fact that encoding an image for transmission by email increases its size by about 33% the practical limit for the file size of a photograph or image is around 180kB.

Resizing a full colour photo

Resizing a photo can be done using any good image software, such as Paint Shop Pro or Adobe Photoshop. A useful freeware utility allowing you to easily resize multiple images is JPEG Resizer, which you can download from the link at the bottom of this page. You can also resize individual images online with the Picture Packer utility in the 'My Account' section of the UKTC website.

There are two steps to reducing the file size of a full colour image such as a photo from a digital camera. The first is to adjust the display size of the photo.

When sending an image by email assume that it will be viewed on screen rather than printed. An average computer monitor has a display resolution of about 75dpi (dots per inch). In order to achieve a screen display size of 8 × 6 inches (200 × 150 mm) this requires an image of 600 × 450pixels.

In Paint Shop Pro this is done from the Image > Resize... menu.

Screen grab

Having adjusted the display size of the image it's time to save it using an efficient file type.For full colour images such as photographs always save your image in the JPG format. The JPG format is highly compressed, and allows a good deal of control over the level of compression. The compression used is 'lossy', which essentially means that the more compression you use, the poorer the quality of the image. You will need to experiment to find a level of compression that produces a suitably small file size, but retains sufficient quality.

In Paint Shop Pro, adjusting the compression level can be done from the File > Save as... dialogue box by clicking the "Options" button. You can also click the "Run Optimizer..." button from the Save as dialogue box to give you finer control and see a preview of the saved image and its file size.

screen grab

Useful links

  • Picture packer
    An online utility for resizing JPG images. You must login with your usual UKTC email address and password to use this.

Downloads

Zip
JPEG Resizer (492.9kB)

A handy freeware utility for bulk resizing of JPEG images, from the folk at http://www.virtualzone.de/