My long birding lens is a 100-300mm whose lowest f stop is f-4. There is no faster lens this long. This IS the faster lens. The other was f-4.8.
If you don’t take pictures and use lenses, you probably have no idea what an f stop is, but for the rest of you, you know that an f stop indicates how “open” the lens diaphragm is and how much light will allowed in. Are you still with me? To make this even more entertaining (and confusing), the bigger the opening, the smaller the number is for the f stop. Do not ask me why. Whoever invented cameras way back when made that decision. The numbers never made any sense to me. You just memorize them, or at least you did when I started photography, fifty years ago.
Despite the fact that almost all cameras work well in automatic and if your eyes are like mine, probably better, some of us persist in trying to take pictures based on the lens aperture or “film speed.” There is no film, but it used to be film speed. Today, it’s ASA or something like that. I let the camera take care of it.
The manual camera I used when I began taking pictures had no battery. It had no electronics, not even a light meter. We used handheld meters. Also, there was a piece of paper inside the Kodak film box that told you what settings to use for different kinds of light. We called it “the paper meter” and it worked surprisingly well. There were only three things (other than what film to choose) you needed to learn: f stop (lens aperture), shutter speed (how long the shutter stays open), and of course, remembering what speed the film is. It was easy to forget which film you loaded, especially if you often changed the kind of film you used.
The camera didn’t inform you. You couldn’t open the camera because it was film, so if you forgot, good-bye photos. In those days, you had to pay for all those blurry, bad pictures. Photography was more expensive. Now you pay for the camera and lens, but you can take thousands of pictures and you don’t have to keep paying. That’s huge. No wonder we moved with such enthusiasm into digital photography.
So this is about light. Not the light in the picture, but the light I didn’t have enough of when I took the pictures. Not to mention the nearly dead battery that I should have changed before I started taking pictures. The battery marker was flashing orange, a bad sign because if the battery is nearly dead, there’s not a lot of zip in the camera,
The light was low. It was a few minutes before sunset. There was some light, but not much. My 50mm f-1.8 lens would have worked. Even an f-2.8 lens would probably have been okay. The f-4 long lens didn’t do fine. Every picture I took of the lovely Cardinal was blurry. Twenty shots, twenty blurs. I deleted them.
So there’s starlight in all of us, but it isn’t always enough to take a clear shot at sundown in mid-winter using a 100-300 f-4 telephoto lens. So if your camera needs a fresh battery? For heaven’s sake, put one in. If the bird flies away, so be it but the pictures you take with your nearly dead battery aren’t going to be great anyway.
These are not the same pictures I’m talking about. These are better, but I couldn’t publish the others.
Photography is all about light. If you don’t have it, pictures don’t happen.