A test shot with a recently acquire 10 and 7 power diopter close up lens. Any one has an idea how to calculate the magnification ratio for digital ? The size of image in film divided by size of actual subject does not work here since the digital image can be sized to fit a 17 inch or even 21 inch screen - pixels having no real size.
http://www.photo.net/photodb/photo?photo_id=702843
http://www.photo.net/photodb/photo?photo_id=702843