f2.8 why

[wendellt]

hi people

loosing my gear gave me an eye opener and an injection of resourcefulness, i've been using a kit lens 18-70 max aperture f3.5 for the past week
been shooting all manner of things from advertising jobs through to press which led me to this thought

do we really need f2.8 lenses

when i had my 17-35 f2.8, i rarely shot at f2.8 unless i was doing something that required smooth bokeh or massive subject seperation
from background

long ago someone told me lenses with f2.8 apertures had different lens design in order to suck in more light
so even if you stop down theres still an advantage...explain?

so do we really need f2.8 lenses?

[Glen]

Faster AF Wendell because they are sucking in more light. One advantage, besides narrower DOF. Your point is fair, your talent overrides the lens, which is why good gear doesn't necessarily make you a good photographer.

[losfp]

"Need"? Naw...

"Want?" Now that's a different thing altogether

I rarely shoot at f/2.8 either, but I like my f/2.8 lenses for the following reasons:

1) Even if I shoot stopped down, the lens is always wide open when focusing. Therefore there is more light available for the AF sensors.

2) It's nice to have the option to go to f/2.8 if I need it due to bad light or the need to get as thin a sliver of DOF as I can.

3) Because the f/2.8 lenses are seen as the pro range, they tend to build them to nicer standards. I'm sure they could build a 18-55/3.5-5.6 as nice as my 17-55/2.8, but they just don't.

It's the same with camera x vs camera y... IMO you can get great shots with any gear (as long as it hits a certain minimum standard).. but the nicer gear makes it EASIER to get great shots.

Some of us simply need more help than others!

[ATJ]

In addition to the great reasons above...

when i had my 17-35 f2.8, i rarely shot at f2.8 unless i was doing something that required smooth bokeh or massive subject seperation
from background

There's your answer there. No matter how rare, you have found times where you needed it. Even if you don't always use the lens at f/2.8, if the lens is f/3.5 to f/5.6, you can't possibly shoot at f/2.8.

How many times have you been in a situation in a car where wearing a seat belt actually saved your life? Do you still wear a seat belt? You wear one because you don't know when you will need it.

[phillipb]

One more reason is that the sweet spot of a lens is rarely at it widest so the f3.5 lens will probably need to be used at f5.6 or f8 to get the best results. The f2.8 will probably go to f4 so you have more leeway.

[gstark]

when i had my 17-35 f2.8, i rarely shot at f2.8 unless i was doing something that required smooth bokeh or massive subject seperation from background

Andrew's answer is correct.

It's when you don't have it, but you need the features it offers, that makes the point.

And to be truthful, f/2.8 is not optically fast.

[aim54x]

And to be truthful, f/2.8 is not optically fast.

I never would have thought I would say this BUT

I find myself using the 50mm f/1.8 for low light stuff, and this has lead me to want/lust an 85mm f/1.4. I would have to agree that we dont need f/2.8 but it is nice to have for that odd occasion (or if your like me - ie a bad photographer - like to shoot wide open and avoid bringing out the flashes)

I will keep buying f/2.8 for the: build, DOF isolation, better low light characteristics

[ozimax]

IN the past 18 months I have owned 70-200 F4, F2.8 non IS and F2.8 IS. The F4 model was superb, the IS F2.8 was, for me at least, disappointing, and the F2.8 non IS is incredible. However, the only time I think I would need/like/prefer the 2.8 variety is for better bokeh all round. I suppose bokeh is a very subjective subject, but I do like the background blur with the 2.8 lens. Now, my favourite bokeh is taken with the amazing 50mm F1.4 - it's an astounding lens.

My 20c worth (two bob for us old blighters)....

[Mr Darcy]

subjective subject

Oh Please

[ozimax]

Let's lern gooder English!

[gstark]

Let's lern gooder English!

Sorry, Oz, but I must pick you up on this. That statement should read gooderer.

[dviv]

Well spotted Gary!

The definition of irony: The sentence in your signature ending in a preposition

[gstark]

Well spotted Gary!

The definition of irony: The sentence in your signature ending in a preposition

Dave, pay attention: to whom is that quote attributed? Careful, it's a trick question.

[dviv]

Well spotted Gary!

The definition of irony: The sentence in your signature ending in a preposition

Dave, pay attention: to whom is that quote attributed? Careful, it's a trick question.

I know - Only an American

[gstark]

Well spotted Gary!

The definition of irony: The sentence in your signature ending in a preposition

Dave, pay attention: to whom is that quote attributed? Careful, it's a trick question.

I know - Only an American

Not just .... as I said, it's a trick question.

Which # was he?

[dviv]

Not just .... as I said, it's a trick question.

Which # was he?

The West Wing?

[gstark]

Not just .... as I said, it's a trick question.

Which # was he?

The West Wing?

Yes.

So, who actually wrote that line?

[dviv]

So, who actually wrote that line?

No idea? Sorkin?

[gstark]

So, who actually wrote that line?

No idea? Sorkin?

Yep.

There was a very entertaining blog posted on the NYT about a week or so back, from him via one of the NYT journos, and suggesting what might have transpired were Jed to have met Obama. That was my favourite line, but the whole article was a gem, with lots of great insight into what's happening there at the moment.

[Yi-P]

Having f/2.8 does not imply that you have to shoot at 2.8 always. From the good comments made above, it is something there for you when you need it, it is the quality gear that will suit a pro's need.

You might have used the 18-70 as a pro routine for one week, but when it gets over to 1 year, or 5 years, I would have a doubt of it keeping up to as compared to a 17-35, or 24-70 used over 5 years, professionally.

[cawdor]

For me, f2.8 is about being able to shoot in low light conditions without flash and still get a decent shutter speed. There have been many sporting events outdoors where, once the sun was almost down, other photogs with 4.5-5.6 lenses were packing up and I was still able to shoot and not get blurry photos.
As the saying goes, you only miss it if you don't have it.

[Matt. K]

It's also about having more control over the DOF in regards to the the background.

[surenj]

After seeing your work Wendellt I bet you could work successfully with a pinhole f64!

[Oz_Beachside]

i prefer the constant aperture over the zoom focal length that the 2.8 glass provides.