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Lenses & Adapters

Since the distance between lens mount and sensor ( Flange focal distance) is so small on the BMPCC (or any other Micro Four Thirds aka “MFT” Camera), you can adapt almost every lens to this camera with the right adapter. The obvious choice would be to use lenses specifically designed for the native MFT Mount.

But there are a lot of attractive options, some of which are more likely to be useful than others.

Although the focal length of a lens is always the same, a lens designed for a bigger sensor (like a Fullframe, FF, 36×24 mm sensor, also known as 135 format) will project an image circle much bigger than the BMPCC's sensor. For that reason it will have a much smaller Field Of View (FOV) than if the lens was used on a fullframe sensor - the “crop factor” is 2.88. So, if you use a 50mm Lens designed for 35mm fotographic-film (without an optical adapter), this would be like using a 144mm Lens designed for the BMPCC's Super16 sized sensor.

While this is a valid rule, it may also be that any particular lens will have a different coverage than expected. Some older FF lenses display an inaccurate focal length, so a 28mm lens might be 29mm, if rounded to the nearest whole number. Nominally, the FF lens should cover a diameter of 44mm, which gives rise to the 2.88 number. This also is not the case in respect of certain wide lenses, in particular and some would vignette on FF cameras. Software can now remedy this on digital FF sensors, but it would mean that the crop factor for such a badly behaving FF lens would be less than 2.88. Paradoxically therefore, more expensive older FF lenses will have a larger crop factor that the cheaper oem lenses. These lenses also have interesting aberrations that are less corrected than the main manufacturer lenses. It is also possible to play with focal length a little, to get a more desirable wide angle. This would mean losing infinity focus and would not suit some uses.

Be aware that the idea of “crop factors” is just to give you a better imagination of what the FOV of a lens you familiar with, will be with a different sensor / film size. That also means that there is no “correct” crop factor, like many people state. If you are used to Super35 (which was the motion picture standard) or shooting on APS-C sized sensors, the crop factor of the BMPCC (in comparison with that format) is 2x. Many people prefer referring to a crop Factor in relation to FullFrame (as explained above) since that is their main point of reference i.e. what FOV a 50mm lens has. There is an excellent article on wikipedia if you have trouble understanding the concept of crop factors.

MFT Lenses

If you use a MFT (micro4/3) lens on your BMPCC it will work without vignetting, since the Super16 Sensor of the BMPCC is smaller than usual MFT Sensor.

Here is an overview of the available MFT lenses: http://www.four-thirds.org/en/microft/lens_chart.html

But for a more complete listing: https://en.wikipedia.org/wiki/Micro_Four_Thirds_system#Micro_Four_Thirds_lenses

C-Mount Lenses

We decided to make a specific section for c-mount lenses, since there are a lot of things to know and look out for with those.

C-Mount Lenses

B4 Lenses

Focal Reducers

Telescopes are similar to camera lenses in many ways and have used a reducer lens for some time, to brighten the image formed, so that it can build up more quickly on a digital sensor. Metabones introduced a special kind of lens adapter they branded the “Speedbooster”, which features optical elements that will reduce the size of the projected image, with two advantages: The projected image is reduced, and therefore also fullframe or APS-c or m4/3 lenses and their different focal lengths suddenly are wider on a smaller sensor. The second advantage is that the Lens_speed is enhanced, as more light reaches the sensor per unit of time.

Ever burned something using sunlight and a loupe? Well thats basically what they are doing there. Fortunately there are some Chinese companies that have picked up this “brilliant” idea and manufacture cheaper versions, with a variety of lens conversions available. One good example is the RJ Lens Turbo.

Other Adapters & Focal Reducers

There are adapters for all kinds of lens mounts, even a lot of Focal Reducers for different mounts (although they are usually not reducing specifically for the BMPCC Crop factor reduction but MFT in general). A few adpaters to MFT that are known to exist: Kiev, Minolta MD, Microscope Lens Mount, B4, Pentax 110, Leica, M42 etc.pp.

Wide-Angle Options

There are several options for wide-angle lenses that work with Super16 sized sensors, both in the MicroFourThird World and in C-Mount. Since the larger percentage of C-Mount Lenses have not been built to cover S16 Sensors, but 1/3, 1/2, 2/3 or Normal 16 sized images you have to be careful when buying a Zoom and expecting it to work on the full focal range.

Since a 16mm Lens on the BMPCC roughly equals a 50mm lens on fullframe, everything below 16mm could be considered “widish”.

Some popular Options:

Nikon F mount lenses (can go on a focal reducer for an even wider FoV)

C-Mount New

C-Mount Vintage

MFT Zooms

MFT Primes

More Information

lenses_adapters/start.txt · Last modified: 2018/10/03 10:05 by 109.220.204.199