Such a beginner question, but i just have to ask...

dan.rpo · Apr 1, 2009

so...what are the main advantages of a lens with a very high aperture (ex: f/1.4 or 1.8, even 2.8) besides the ability to snap photos in low light situations without a flash?

i have a nikon d40 and am interested in purchasing the 35mm af-s f/1.4 (maybe its 1.8, i forgot). thanks!

Garbz · Apr 2, 2009

The low light obviously helps but only against a kit lens. The difference between 2.8 and 1.8 is only 1 stopish, 1.8 and 1.4 is only 1/3rd. Then you have to deal with the depth of field too so even at low light you may not want to shoot wide open.

dan.rpo · Apr 2, 2009

so than what are te advantages of having such a large aperture?

Dwig · Apr 2, 2009

Advantages:

1. wider aperture, if used, yields higher shutter speeds, all else the same. This can be an advantage in low light shooting. It can, with long lenses, allow for better hand held images.

2. wider aperture, again if used, has less depth-of-field. Shallower DOF can be very effective artistically, particularily in portrait work. It also makes manual focusing much, much easier and more precise.

Chris of Arabia · Apr 2, 2009

As a general rule of thumb, f/2.8 and wider will be found on better quality lenses, but this isn't always the case.

Disadvantages:

higher cost
heavier lenses
more difficult to focus precisely, particularly when close to the subject

mrodgers · Apr 2, 2009

Not a user of large apertures with my lack of a dSLR, but I've been reading plenty lately in the threads about the large aperture lenses. Thus, this hasn't been mentioned yet....

Stopping down a large aperture is said to net a sharper image than a lens with a smaller aperture. Example, stopping down a f/2.8 to f/4.0 will result in better sharpness than an f/4.0 max lens.

dan.rpo · Apr 2, 2009

hm,interesting last post mrodgers. well....i have the funds to purchase either the nikon af-s 55-200mm VR f/4.0 or the nikon af-s 35mm f/1.8.....what would make a better purchase? i know they are two TOTALLY different fields.

i was going to buy the 55-200 because i like doing urban candid pics, such as the city population and street shooting. but the low light aspect and sharpness of the high aperture is making me think twice.

Big Mike · Apr 2, 2009

It most cases, a large aperture lens is going to be a premium lens. For example, most of Canon's ultra fast lenses (F1.2 & F1.4) have the 'L' designation...which is their top of the line. So besides having a large aperture, they also have the best quality glass, weather sealing and overall quality.

Also, most of the time, a prime (non zoom) lens will give you better image quality than a zoom lens. (although zoom lenses are much better than they used to be). To further that, you will usually find that a short range zoom (24-70mm for example) will be a lot better than a wide range zoom lens (18-200mm for example).

As for what you should choose...it's a very personal decision. Some people like prime lenses because of the high quality, large apertures and the fact that it forces them to use their feet to zoom and also to thing more about their shot before they take them. Some people like zoom lenses because of the convenience.

paulk_68 · Apr 2, 2009

mrodgers said:
Stopping down a large aperture is said to net a sharper image than a lens with a smaller aperture. Example, stopping down a f/2.8 to f/4.0 will result in better sharpness than an f/4.0 max lens.

Hmm, how many lenses max out @ f/4? I took some shots recently with my cheap kit lens with my aperture @ f/22. Save money on glass by buying a camera body that handles high ISO speeds with minimal noise.

tsaraleksi · Apr 2, 2009

paulk_68 said:
Hmm, how many lenses max out @ f/4? I took some shots recently with my cheap kit lens with my aperture @ f/22. Save money on glass by buying a camera body that handles high ISO speeds with minimal noise.

I think you have something very confused, but I'm not entirely sure what it is...

dan.rpo said:
hm,interesting last post mrodgers. well....i have the funds to purchase either the nikon af-s 55-200mm VR f/4.0 or the nikon af-s 35mm f/1.8.....what would make a better purchase? i know they are two TOTALLY different fields.

i was going to buy the 55-200 because i like doing urban candid pics, such as the city population and street shooting. but the low light aspect and sharpness of the high aperture is making me think twice.

The 35 is a vastly better lens for doing city shooting. So, buy the prime!

mrodgers · Apr 2, 2009

paulk_68 said:
Hmm, how many lenses max out @ f/4? I took some shots recently with my cheap kit lens with my aperture @ f/22. Save money on glass by buying a camera body that handles high ISO speeds with minimal noise.

Even I know how very wrong that suggestion is.

bdavis · Apr 2, 2009

Besides don't a lot of lenses start losing resolution when they get past f/16? I read that somewhere...

paulk_68 · Apr 2, 2009

tsaraleksi said:
I think you have something very confused, but I'm not entirely sure what it is...

If you are buying a f2.8 lens to get a sharp picture at f/4, you are wasting your money. Simple.

There are millions of ways to achieve an end result in photography. A camera body that can handle high ISO speeds (with little noise), can use faster shutter speeds and higher aperture settings; it is more cost effective in the long run than buying countless "super fast" lenses,.. in my opinion.

tsaraleksi · Apr 2, 2009

paulk_68 said:
Hmm, how many lenses max out @ f/4? I took some shots recently with my cheap kit lens with my aperture @ f/22. Save money on glass by buying a camera body that handles high ISO speeds with minimal noise.

paulk_68 said:
If you are buying a f2.8 lens to get a sharp picture at f/4, you are wasting your money. Simple.

There are millions of ways to achieve an end result in photography. A camera body that can handle high ISO speeds (with little noise), can use faster shutter speeds and higher aperture settings; it is more cost effective in the long run than buying countless "super fast" lenses,.. in my opinion.

But you're still not wasting your money. A lens behaves very differently depending on the aperture-- if a 2.8 lens is sharper at 4 than a 4 lens, then you shoot a sharper image at f/4. That's an advantage. Unless you shoot nothing but flowers and landscapes, or maybe only work in a studio with strobes, the ability to shoot faster is an advantage, even on bodies that perform well at higher ISOs.

Not to mention that there are lots of other advantages that come along with faster lenses aside from the inherent 'better stopped down' issue. Mainly, you can't open an f/4 lens to f/2.8 but you can do the opposite.

paulk_68 · Apr 2, 2009

tsaraleksi said:
But you're still not wasting your money. A lens behaves very differently depending on the aperture-- if a 2.8 lens is sharper at 4 than a 4 lens, then you shoot a sharper image at f/4. That's an advantage. Unless you shoot nothing but flowers and landscapes, or maybe only work in a studio with strobes, the ability to shoot faster is an advantage, even on bodies that perform well at higher ISOs.

Not to mention that there are lots of other advantages that come along with faster lenses aside from the inherent 'better stopped down' issue. Mainly, you can't open an f/4 lens to f/2.8 but you can do the opposite.

Yes, I agree, but I'm looking at it from the issue of cost. The camera body is just the beginning of what people spend on photography equipment, again it is just my opinion, your money will go much further if you start with a decent camera body. Who wouldn't love to own a 600mm f/2.8 lens?