Right. Here’s one they don’t always tell you (this post is only relevant if you’re interested in the nerdier, more technical aspects of making photographs by the way).
Tentatively leaving aside the massively important task of actually looking at and seeing your subject (no easy job), this is a quick look at the tools for the job.
Whatever lens you own, whether it’s a very expensive and well-made lens or whether it’s all you can afford and frankly a bit budget, there is a trick to help you get the most out of it in terms of it producing, sharp, quality images. And the trick is this. ALL lenses produce immesuarably better images if you close the lens down by a stop or two.
The real-world tip here is that when photographing in low light, for atmosphere for example, one is often forced to open the lens right up to get as much light in as possible – to say f2.8. Even though that’s a setting that’s there for you to use, it really is a last resort. If you were to close it down to just f4 – not much of a difference – the image quality leaps. Try it with a digital camera if you have one. Say you were at 60th-f2.8. You’d be inclined to think that for image quality, it’s worth hanging onto the 60th to perhaps avoid blur. A fair assumption but a much better move, in my opinion, is to brace yourself for a 30th and close the lens to f4.
The difference isn’t subtle. In nearly all my tests with various lenses, f2.8 looks ‘alright’ and by contrast f4 looks ‘great’.
I should point out that there are extremely well made lenses available (Leica for example) that are spectacular wide open but they’re rare. And expensive.