I am thinking of doing concert videography next year, and will need to get a lens with more reach than what I currently have. At the moment I have two lenses:

• Tokina atx-i 11-16mm f/2.8
• Tamron 24-70mm f/2.8

Both lenses are used with a speedbooster. The camera I will be using is an OG BMPCC (1080p version). I know that my current lenses will be unlikely to give me quite enough reach for a concert, so I started looking into a 70-200mm lens. I have filmed one concert already, and for that I rented a Sigma 70-200mm f/2.8 Sports lens, and it worked beautifully.

Unfortunately, I do not have the budget to acquire a Sigma 70-200, so I looked into an equivalent Tamron. While doing so, I stumbled across the Tamron 70-210mm f/4 lens, which is half a third of the cost of their f/2.8 lens. With the speedbooster, should I be ok to film in the low light type of environment that concerts tend to be in?