To know the recommended cable length from laptop vga port to epson digital
Projector and or max length advised

How far do you have to go?

Here are 25 and 50' extension cables; http://catalog.belkin.com/IWCatSectionView.process?Section_Id=206195

You might have to use a specialized device to drive long distance such as: http://www.networktechinc.com/cat5-vga.html