The Issues with long telephoto lenses
Well first there’s the size. Lenses in the 300mm range and above tend to be big and heavy. As designers try to make the lenses faster ( bigger aperture) to let in more light so the size and weight of the lens increases, exponentially heavier as the auto focus mechanism gets bigger to handle the bigger elements inside the lens.
But more light allows shorter depth of field shots but more importantly faster shutter speeds. It’s a trade-off between the final result of the image and the size/portability of the lens.
Such lenses need a good support, there’s just no way to get a steady shot at anything but the highest shutter speeds. A good sturdy tripod is a must, a monopod can act as alternative.
Monopods are great for being able to manoeuvre your camera (and big lens) quickly. And they’re a good compromise between stability and portability. And more important is they help you get the shot, especially in fast moving action settings, such as sports venues.
But tripods, (make sure it’s adequate enough for your biggest, heaviest lens) along with a cable release will produce the best image that the camera/lens combination are capable of. But in these situations your somewhat anticipating the shot, where the action might be. So, as with everything in life, there’s a compromise. a trade-off between rock solid and pin sharp images –to – portability and getting a shot, any shot. As long as shot has the essence of what you require within the physical constraints of the physics.