There have been, among the responses to other questions, comments about "losing" depth of field as you increase negative size. That is, there is less depth of field in a 6x7 negative than in a 35mm. I think that this whole argument is wrong and more than a little confusing. Let me explain. I have always thought that depth of field (DOF) was a zone of sharpness that extends both in front of and behind the point at which a lens is focused. Furthermore, depth of field is dependent on three things only: the distance from the lens to the point of focus; the aperture at which the lens is set, and the focal length of the lens. For example, if three different format cameras are all equipped with a 45mm lens, focused on the same point, and set with the same aperture, then the DOF will be exactly the same in all three photographs. It is totally unaffected by film format. Admittedly, bigger film formats like 6x7 have larger image circles, and will include more "stuff" in the frame than 35mm. Some of the extra "stuff" will be out of focus if it is outside the depth of field, but it is wrong to say that there is any loss of DOF.