The 125C with coarse thread #16 Orange Filter from Tiffen is a filter designed to build contrast in black and white photography. The effect of the contrast will be greater than the #15 yellow when shooting B&W landscape, marine, or aerial photos. Therefore, making skies more dramatic and darker. The filter has a filter factor of 3, so you must increase by 1 2/3 of a stop of your exposure to compensate.
Tiffen filters are not dyed, but are manufactured by using ColorCore technology. This process laminates the filter material between two pieces of optical glass and grinds down and polishes the glass. The glass is then mounted to the metal ring, which after that can be screwed onto the lens for the desired effect.
Strong contrast in B&W images
Ideal for landscape, marine, or aerial photography
Renders sky more dramatic and darker