Diana F+ Lenses can do a whole lot of fantastic things but they won´t overrule physics. Your film or sensor format sets the boarders to the lenses field of view…
The field of view you get from a lens depends on its focal length and the format the film/camera sensor has. If you use your DianaF+ Lenses with the adaptors you´ll propably use them on a 35mm Camera instead of a medium format snapshooter as the Diana is one. And yet the filmsize has changed – which results in a cropped exposure.
The bigger the film format/ camera sensor the bigger the picture angle will be – which on the other hand means the smaller your film or sensor the smaller the angle of field cought on film will be. Thats why you don´t get a full fisheye effect when using the Diana F+ fisheye lens on a 35mm SLR camera. For digital SLRs with a non fullsize APS-C sensor the crop-factor is even bigger than for 35mm film. To get an idea of what each lens will do on a 35mm and APS-C sensor camera we did some math for you.
Even if the focal length of a lens won´t change – used on different film formats the effects can differ – the focal lenght numbers given for 35mm and APS-C sensors describe the focal length of our Diana F+ lenses equivalent to 35 mm and digital APS-C sensor SLRs.
The Diana F+ 38mm Super Wide Lense on a 35 mm is equivalent to a 72mm standard lens. Used on a APS-C sensor DSLR it has the effect of a 115mm tele lens!
The Diana F+ 20mm Fisheye Lens used on 35mm cameras has the effect of a 38mm Wide Angle Lens. On an APS-C sensor it´s equivalent to a 60mm lens.
The Diana F+ 55mm Closeup & Wideangle Lens is equivalent to a 105mm telefoto – lens when attached to your 35mm camera. Mounted on an APS-C DSLR you get an amazing 170mm super – tele effect.
The Diana F+ 110 mm Telefoto Lens in combination with any 35mm camera will act like a 200mm super tele lens. With an APS-C the Telefoto Lens is equivalent to a 320mm super – duper – tele lens!
Note: The focal lenght of a lens won´t change if you use different film formats but the film format determines which part of the image the lens prduces actually is on film! What happens can be compared to what´s known as crop factor – when you are using a 35mm SLR lens on a digital SLR camera with APS-C or similar sized sensors.