Need Micro Four-thirds lens for Low Light Live Events

We just purchased three BM Studio Camera 4K. We have purchased some of the panasonic lens. We find them to be dark. What is the best low light lens with wide focal range?

Help>>>>>>>>>>>>>>>>>

It's hard to make specific recommendations without knowing what Panasonic lenses were too dark for you and what focal length range you're looking for.

In general you can get better low light performance by using a Metabones Speed Booster (or equivalent) and attaching a full-frame Nikon or Canon mount lens. The Speed Booster concentrates the light from the larger coverage area of the lens and gives you a brighter image and a wider effective focal length.

https://metabones.com/products/?c=blackmagic-MFT

The widest aperture native Micro 4/3 zoom lens is the Panasonic Leica 10-25mm f/1.7.

There are also several native f/2.8 aperture zoom lenses:

• Olympus 7-14mm f/2.8
• Panasonic 12-35mm f/2.8
• Olympus 12-40mm f/2.8
• Panasonic 35-100mm f/2.8
• Olympus 40-150mm f/2.8

None of these lenses have an especially wide zoom range (by the standards of broadcast video zoom lenses). Olympus makes a 12-100mm f/4.0 lens which has a decent range, but does not have an especially fast aperture.

Note that none of these lenses have power zoom capability. If you need that you are stuck with the four native Micro 4/3 power zoom lenses:
https://www.blackmagicdesign.com/support/faq/59009

As Steve mentions, if you use a Speed Booster you can get an effective increase in f-stop from full-frame or even APS-C lenses. The best option for the Studio Camera 4K is probably the Super 16 (0.58x) Speed Booster which gives a boost of about 1 2/3 stops in light gathering. If you pair these with something like the Sigma 18-35mm f/1.8 or 50-100mm f/1.8 lenses, it will effectively turn them into f/1.0 zooms.

Also keep in mind that a faster lens will be brighter but will give you a shallower depth of field so that less of the image will be in focus and you'll have to focus more precisely on the plane that you do want to be in optimal focus. It's even more of an issue at longer focal lengths. So before buying a lens and speed booster to achieve an effective f/1.0 aperture make sure you're taking advantage of the gain (ISO) and exposure controls in the camera to get the best compromise between brightness, depth of field, and noise. If you have a choice of frame rates then you can also shoot at a slower frame rate with a longer shutter speed to get a brighter image.

Another thing to remember is if you're using a speed booster, you won't get remote lens control of the iris.

Remote iris control should work with the Canon EF Speed Boosters.