For those coming from a digital world to test the film waters with medium format cameras, the 35mm crop factor for medium format lenses and film types can be confusing when a 50mm lens can be ultra-wide and a 90mm lens is considered a normal lens….6 x 6 Crop Factor = 0.55.

A 35mm lens on a camera with a crop factor of 1.6x, has a 35mm equivalent of 56mm. A 50mm lens on a camera with a crop factor of 1.6x, has a 35mm equivalent of 80mm.

35mm film has a standardized frame size of 24mm x 36mm (864 sq. mm of film surface). An advantage of 35mm is because it’s smaller.

Multiply the focal length printed on the lens by 1.5 to obtain the 35mm-equivalent focal length of a lens mounted on a camera with an APS-C sensor. For example, if you mount a 50mm lens on an APS-C sensor camera such as the ILCE-6000, you’ll get the same view as a 75mm lens on a full-frame camera (50mm x 1.5 = 75mm).

I have a sweet collection of Nikon full frame lenses that span from 28mm on the wide end to a 105mm telephoto. These optics work great on both my 35mm film cameras and the digital bodies as well.

No, f/stop does not vary with sensor size. Nor does focal length vary with sensor size. The lens remains totally unaffected by the sensor. HOWEVER, the field of view that the cropped sensor can see and capture is seriously affected in the smaller sensor.

Aperture, expressed as f/x is not changed since f is not changed. The only effect the crop factor has is to give you an angle of view on your crop sensor that would be roughly equivalent to that of a 75mm on a full frame sensor.

A 35mm lens is a lens with a focal length of 35mm (millimeters). Focal length is the length from the optical center of the lens to the camera’s sensor, but that’s not super important to remember. The 35mm is an extremely popular lens choice and a crucial tool for any photographer/cinematographer.

While a 50mm prime lens will give you a field of view of just under 40 degrees, the 35mm prime lens gives you 54.4 degrees — significantly wider.

Consider the 35mm camera using 85mm f/1.8 for subject isolation in portraits, the 6×7 portrait lens is often a 150mm f/4. Note that Bronica GS-1 was built to be a lighter 6×7 than Pentax and Mamiya. All lenses are leaf with maximum speed of 1/500 and the lenses are slower f stop which keeps the lenses lighter and smaller.

B&H Photo has a LENS COMPARISON CHART for Mamiya 6X7 lenses. It’s difficult since the aspect ratio of the format are different. I use a schneider 110mm with 6×7 and it *feels* to be about 55mm equiv. 90mm feels wider than 50mm.

Even that is a loose definition, because for many, 35 mm is the lens they “normally” use for 35 mm film, 75 mm and 105 mm respectively. Part of using a camera is learning to “speak” its language, which includes using the controls without thinking and choosing a lens.

Since lens weight was brought up, it’s also worth remembering that RB/RZ lenses are heavier out of necessity than an otherwise 100% comparable lens for a GS-1, Pentax 67, or even Mamiya 7. The reason for that is that the RB/RZ lenses have to cover 7×7 at a minimum, while the others only have to cover 6×7. Me too.