When operating via callbacks, the WebChartControl control enables callback results generated for the control on the server to be sent compressed for compression-enabled browsers, improving application performance. Callback result compression provides faster transmission time between the server side and compression-enabled browsers. Enable the EnableCallbackCompression option to more efficiently use available bandwidth.
If callback result compression is enabled, the WebChartControl checks whether the target browser that sent the requested callback is compression-enabled (by analyzing if the Accept-Encoding request header matches the gzip or deflate value). If content encoding is allowed by the browser, the WebChartControl compresses) the callback result (using the corresponding encoding scheme as it is generated for the control on the server, and sends the compressed response to the browser.
Don't enable callback result compression if IIS HTTP compression is enabled.