Some members have been having problems meeting our new Competition specification for digital images, because of the asymmetric sizing requirements. Users of Picasa or PS Elements in particular have a problem because the programs do not offer the ability to change both dimensions. So instead I am suggesting a better solution, to use the freeware program IrfanView to perform the resizing. Full instructions are now included on the PDI Specification page.
For Mac users, the problem appears to be the Mail program – you have to ensure you have checked the “Actual Size” box when attaching images, or they will be sent much smaller than required.