Photographing natural fabrics produces a different photo than photographing man made fabrics.  For example, polyester reflects the light but silk absorbs the light.  The difference is noticeable especially in wedding photographs.

The white polyester shirt on the groom and groomsmen will stand out as very bright white whereas a white silk gown will be a much softer white, almost a creamy white.  Why?  Polyester color is added to the fabric while it is liquid before the liquid is made into yarn.  The silk fiber is dyed after the silk worm produces the silk.

For a good example, search online for Kate Middleton’s wedding veil which is silk tulle.  The drape and transparency of the silk veil is obvious while a polyester tulle has less drape and transparency.

The silk tulle from Kate Middleton’s veil as well as the whiter polyester tulle are both available in the Fabrics.net store.