Medium format mirrorless systems are a great way to get into photography with a sensor that’s larger than a full frame 35mm sensor, so long as you can afford the higher price point. Whilst cameras like those of the Hasselblad X System, and the Fujifilm GFX Format are pricey, they are still less expensive than traditional “full frame medium format” cameras which use even larger sensors.
When moving from a full frame (or perhaps APS-C) DSLR, one of the confusing things to understand can be the focal lengths of lenses for a medium format system. We are so used to seeing focal lengths in terms of 35mm cameras, that it’s hard to picture the kind of field of view that a medium format focal length will give. For example, 45mm on a medium format camera will give nothing like the same view as a 45mm lens on a full frame 35mm camera.
To compare one with the other, we need to know the crop factor of the sensor in the Hasselblad X System. Crop factor is simply the ratio of the diagonal sensor dimensions, and knowing the vertical and horizontal dimensions we can easily figure this out.
THE MATH WORKS OUT AS FOLLOWS:
Full frame sensor dimensions: 36mm x 24mm therefore diagonal dimension is √(362 + 242) = 43.27mm
Hasselblad X System sensor size: 43.8mm x 32.9mm therefore diagonal dimension is √(43.82 + 32.92) = 54.78mm
Crop factor for Hasselblad X System = 43.27/54.78 = 0.79
Typically we are used to seeing crop factors of more than 1. For example, APS-C cameras have a crop factor of either 1.5 or 1.6, whereas micro four-thirds cameras have a 2x crop factor. Since the Hasselblad X System has a larger sensor than that of a full frame camera, the crop factor is less than 1, meaning that XCD lenses of a particular focal length, will show a field of view that is equivalent to a much wider focal length in 45mm full frame terms.
Hasselblad XCD Lens Equivalent Focal Length Table
Using the calculated crop factor of 0.79, we can now see the 35mm equivalent field of views for all the Hasselblad XCD lenses. Note that the last 3 lenses in the table have been confirmed by Hasselblad to be “coming in 2017” but the maximum aperture of these ones is not yet known.
|Hasselblad XCD Lens||Equivalent 35mm Focal Length||Equivalent Aperture|
|XCD 21mm f/4||17mm||f/3.2|
|XCD 30mm f/3.5||24mm||f/2.8|
|XCD 35-75mm f/3.5-4.5||28-60mm||f/2.8-3.3|
|XCD 45mm f/3.5||36mm||f/2.8|
|XCD 65mm f/2.8||51mm||f/2.2|
|XCD 80mm f/1.9||63mm||f/1.5|
|XCD 90mm f/3.2||71mm||f/2.5|
|XCD 120mm f/3.5 Macro||95mm||f/2.8|
|XCD 135mm f/2.8||105mm||f/2.2|
|XCD 135mm f/2.8 + 1.7 converter (f4.8 with converter)||178mm||f/3.5|