ExpoDisc, the pioneer in diffusion filters that allow photographers to balance colour at point of capture, today announced the Expo Aperture Depth-of-Field Guide, a small circular pocket guide that enables photographers to quickly determine the maximum and minimum depth of field for a given focal length and aperture size. The new Depth-of-Field Guide is compatible with all film and digital SLR cameras.

Expo Aperture Depth-of-Field Guide
The new Expo Aperture Depth-of-Field Guide is printed front and back on two tough plastic discs that rotate against one another, somewhat like a simplified, compact circular slide rule. It is slightly larger than a credit card and comes packaged in a durable plastic pouch. The depth-of-field guide comes with advanced instructions. Given the aperture setting, the actual focal length of the lens and the distance to subject, photographers using any digital or film SLR camera can quickly determine the precise depth-of-field for their shot, literally seeing their options at a glance.

Easily regain control of your images
"The new Expo Aperture Depth-of-Field Guide can help you quickly and easily regain control of your images. You will know in seconds the largest possible aperture for your desired depth-of-field, which also enables the fastest possible shutter speeds and helps image sharpness," says Erik Sowder, President of ExpoImaging. "Its simplicity and ease-of-use will appeal to both beginner and professional."

Education
The Expo Aperture Depth-of-Field Guide is of particular interest for students and lecturers in the educational field:

"As a tool for the teaching or learning of photography, the Expo Aperture Depth-of-Field guide is peerless in assisting understanding of one of the most important and least understood areas in photography: depth of field. Because of the simplicity and clarity of its design, and its orientation, it is the best graphic aid in teaching depth of field that I have ever seen.

"I have now taught several dozen beginning photographers from San Francisco State University the principles and application of depth-of-field and never in my teaching career have I found students to so quickly and profoundly understand the concepts and their application." Professor Neal White, Coordinator, Area of Photography, San Francisco State University, CA