Hi, Shel Belinkoff wrote: > > Recent threads have got me to thinkin' about this new-fangled colour > film. B&W film generally has but one layer, and color film has three or > four layers. Now, when one focuses, does all the light converge on one > plane?
This is something which has intrigued me since the introduction of "apo" lenses. Assumedly, film manufacturers are striving to create better colour, etc, and thereby causing the film to become marginally thicker. Contrariwise, lens manufacturers are convincing us that we should be buying lenses which focus light of all colours in the same plane. A paradox of the first order, unless..... the margins of error are so small as to be unnoticable. No, perish the thought that this could all be marketing speak! mike - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .