A kid cannot fake an expression but an adult can. When dealing with a kid, the photographer must be really fast to capture the expressions. The expression lost is lost forever. Similarly, while capturing the portraits to establish lifestyle, the expressions of the subjects cannot be faked. The photography must be candid. It would be unjust of the photographer to request the subject to recreate a scene. The photographer must be really fast in these situations. When the sensor gets more ambient light, it becomes easy for the photographer to capture images at a higher shutter speed. We need a wide aperture lens to do this. An f/1.2 or an f/1.4 lens or even f/2.8 should help.
Apart from the lenses, it is advised to carry a reflector or a flashgun depending on the need.
This is totally at the photographer’s discretion. A good photographer can make the best of a kit lens as well. It is better to explore the kit lens and the existing lens than to invest in the expensive lenses without knowledge. If you have the plan well in advance, you can actually make use of flashguns and reflectors to get the light you need and shoot accordingly.
About 80% of the time, we would need a prime lens. A 50mm prime lens comes with different apertures and the cost varies from 5 Thousand to a lakh. A proper plan can help you save money and get excellent images. Welcome to the world of Portraits.