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Photography Tip of the week #10

What to look for when buying lenses?

Its is always a serious decision to spend your hard earned cash on a new lens, but what should you look at when making you choice of lens to buy? This is a common question i get asked by people who attend the courses i run.

There is an old saying "always buy good glass" The principle behind this being that if you buy a good lens it will last for years and years and I have had some of my best lenses for 10+ years and the same lens is on sale today.

So lest's have a look at some decision points

1: What are you going to use the lens for? This might sound simple but its a good place to start - You want to take close up images - You need a macro lens - You want a single lens you can take on holiday that will do everything A large range zoom 35 - 200 Answer: Understand what you need

2: Format type of lens A Full frame (FX) or cropped sensor (DX) lens. Full frame lenses are more expensive as they have more glass in them and are generally professional standard lenses. A full frame lens will work perfectly well on a cropped sensor camera but a cropped sensor lens will not work well on a full frame camera as you will get dark corners to your images or vignetting. So you need the right type of lens for the camera. Answer: You may ned to buy for the long term if you can

3: Image Stabilisation If this is an option on the lens then you should go for this as it will give sharper images a smaller f stops. Answer: Must be a good addition

4: Zoom and Wide angle If you are buying a wide angle lens the every single mm of focal length you can get will make a difference. Its easy to see the difference between a 10mm lens and a 15mm lens. Whith the zoom side of things its not so easy to see the difference between a 300mm lens and a 350mm lens Answer: Pay for meaningful gains

5: Beware wide range zooms you may look at things and say that instead of buying 3 lenses (12-24mm), (24-70mm), (70-600mm) you could simply buy a 12 - 600mm lens This may not be such a great idea as a lens like this will in all probability underperform in all aspect - image soft - image softer at the edges - poor f stop range f5.6 to f8 Answer: Make sure you read good reviews and if it sounds too good to be true it probably is

6: If you can keep with consistent lens cap size then that is always a help. If we look at our three lenses again (12-24mm), (24-70mm), (70-200mm) and they all have a 77mm lens cap fitting then this means that a single fiter say a polarising filter will fit all three lenses and will save you money and weight. If you not sure of the filer size for a lens then its alays printed inside the lens cap. Answer: Check the lens specification

7: Avoid lenses that zoom bigger this is not a massive issue but some zoom lenses increase in length when you zoom them and they can end up quite large and hard to manage Answer: Check the lens specification

8: Buy fast glass A fast lens is a lens where the lens operates to f1.4 to f4 across its range So for example a) 70-200mm, f2.8 b) 70-200mm, f5.6 - f8 So (a) is a fast lens as its 2.8 and its 2.8 "across its range" which means what ever focal length you are at you will be able to shoot at f2.8 and it will be the expensive lens. (b) on the other hand will be able to shoot at f5.6 at 70mm and f8 at 200mm so neither of these are "fast2 and it get worse as you zoom Answer: Check the lens specification

9: Zoom or Prime Should you buy a 70-200mm f2.8 zoom or a 80mm f2.8 prime? The prime will be a sharper lens in general as the glass is not working as hard but is not as versatile as the zoom, however you can move nearer or away from the subject so you do have some zoom capability if you move. Answer: understand what you want

10: Read GOOD Reviews Visit sites that review a wide range of lenses and see what they say bout the lenses you are considering is a good example. Be wary of a review by "terry" who says this lens is great as he has in all probability not done a controlled evaluation and has not reviewed all the other options. Answer: Do your research

10: Get a good deal Second hand lenses can be good value if you purchase them from a reputable company e.g If you are buying new then check your prices e.g.

After all this work enjoy your lens and get out and get some photos taken don't let it gather dust


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