Using the two sliders, choose the quality of the banner. The higher the quality, the larger the banner file will be.
The estimated size of the banner (Flash format) is displayed at the bottom left in real time.
At any time you can click the Preview button to see how the banner will be displayed with the selected settings.
In general, and if the estimated size of the banner is below 500 [kb], it is advisable to keep the maximum quality.