What is the best light for photography? Well, daylight of course, unless there's none available! Flash photography should be considered a secondary light source or a means to get creative. I get results like this portrait of a tattooed gallery curator just using the kit in the pic. Flash can help lift shadows, when balanced properly, but start to underexpose the ambient light and expect your photographs to pop off the page.
How to take better portraits? Off-camera flash will help create dramatic portraits. Using slaves to remotely fire flash away from the lens produces amazing results, even if it's only at arms length using a TTL cable. One flash placed at 45 degrees between subject and lens is a great start for experimentation. Add another and it gets interesting. I often use a third flash behind the subject to create a blip of rim-light.
How to take sharp photos in low light? A sturdy tripod will help. My aluminium Manfrotto weighs 3.5kg, so will take the weight of a Nikon D5 + 500mm lens easily and won't wobble. Clamps, poles, ladders and steps allow me better composition and help to stay steady and comfortable. Stepladders are invaluable on jobs where a little extra height is needed, or I'm penned-in working alongside other photographers.
How can I share photos fast? I don't shoot much on a cell phone so wireless transmitters are the answer on my Nikons. They're used daily in press work to get images to picture desks fast. My Duke & Duchess of Sussex kissing picture was on the screen in Piccadilly Circus and on pic-desks a few seconds after the kiss - although on this occasion I was also hardwired with a LAN cable straight into the camera!