I'm new to Umbraco. I am using Umbraco 5 RC2. I have noticed that when using the uploader to upload images. e.g. the example book area that it saves q image the original size and one which is 100px wide. How can I change the these sizes?
Whilst you're not able to set the image dimensions on the uploader, Umbraco comes shipped with a nifty little component called ImageGen which takes care of most of your needs for displaying images on your website. The code to use this component can be as simple as:
/umbraco/ImageGen.ashx?image=myimage.jpg&width=200
Refer to ImageGen for complete documentation on how to use it.