You know photography is an expensive hobby, right? You think you have bought gears that will last you good years but the next you know, within the next several months of buying one you already want to get a new gear. If you have the war chest, this won’t pose any problem. But if you are an average income earner, it’s safe to say you’d have to deal with all the desire to acquire a new gear.
If you are just staring out, upgrading from a point and shoot to a more sophisticated gear, you could do yourself a favour by starting off with a good lens.
What kind of lens? I would say this, based on my experience: avoid being tempted into buying long zoom lenses because they normally are slow and terrible at telephoto end.
You won’t realise this at first because of the seemingly plausible usefulness of long zoom lenses — they can be an all-purpose lens — but as you progress into your hobby and becoming better experienced, you’d begin to see the dark side of these lenses: they simply couldn’t deliver the kind of image quality you’d expect from them.
These lenses are the kind of gear you would eventually outgrow as time goes by.
For day-to-day shooting, I would recommend starting off with a fast 17-50-ish f2.8 zoom lenses. These are normally good lenses, deliver sharp results and allowing some freedom to control the depth of field which you would find yourself doing a lot as you progress in your hobby.
You will also going to need a fast F1.4 or F1.8 prime lens: either 50mm, 60mm, 85mm or 100mm, preferably macro lens. Some are expensive but others are affordable. Having this lens with you opens up opportunities for macro and portrait photography, something which the 17-50-ish lens is struggling to achieve.
I guess, for beginners, this two-lens setup would suffice. Later of course you can add in more prime and specialty lenses.
… this should have been my lens roadmap; but alas, I was less wiser then. I started off with a 18-250mm, regretted it and bought myself a 17-50mm F2.8, followed by a 100mm F2.8 and a Lensbaby Composer plus Double Glass Optic. If I was wiser then, I wouldn’t have taken that route.