Having an f/1.4 lens and not using it wide open ...

Some comments don't deserve a response.
But, if need be, let's say we're talking 35mm. What options are there faster than f4 in Canon?
35L 1.4
35 f2
16-35 f2.8
24-70 f2.8

Which will give you the best IQ at f2 or f2.8?

Ephur wrote in post #12121072
When I first got my 50mm 1.4 I couldn't shoot in anything other than 1.4, then I started checking out the pics. Yeah, it looks sharp as a knife stopped down to 2.8! Oh, and you get both sides of the face on a 3/4 view!

Same here, when I first got my 50 1.4, I used it exclusively at 1.4. Now I use it wide-open when appropriate for lighting or artistic needs, but I also frequently stop it down to make sure the entire subject is in focus. There are times when the biggest possible aperture makes sense, and times when it doesn't. But that doesn't mean there's no point in having it available.

cancan7 wrote in post #12121219
Well, if you use it at f2.8 or smaller apertures, why not use a fast zoom, yeah it's bigger, but you have much more flexibility.

A bunch of reasons already mentioned:
- much brighter viewfinder (the lens will sit wide open until you squeeze the shutter)
- arguably better optics from the prime over the zoom
- some like the shooting experience of a prime more than a zoom

If you want a fair bit of depth of acceptable focus (i.e. smaller than f/2.8) at a 50mm focal length and you had the time and inclination to do the image the best justice would you pick the 17-55 over the 50L?

Invertalon wrote in post #12121050
Me love some 85L wide open... Stopped down, it just gets eye-bleeding sharp. So it works well on both ends

That is the type of pain that I love. Call me a masochist

Depends on what you shoot. I wouldn't say that with f1.4 lens I never have a need for shooting wider than f2 also. I use my only f1.4 lens mostly at f1.4 but then I am shooting single person shots. With 135mm f2 I was at f2 almost 99% of the time. BUt you shoot base on what you like not what someone else tells you.

smythie wrote in post #12121469
A bunch of reasons already mentioned:
- much brighter viewfinder (the lens will sit wide open until you squeeze the shutter)
- arguably better optics from the prime over the zoom
- some like the shooting experience of a prime more than a zoom

If you want a fair bit of depth of acceptable focus (i.e. smaller than f/2.8) at a 50mm focal length and you had the time and inclination to do the image the best justice would you pick the 17-55 over the 50L?

Does the VF brightness changes between f2.8 and f1.4? I need to look clearly to see if there is a change.

the difference will be two stops. Try setting your lens at an aperture two stops smaller than its widest setting (eg your 1.4 at 2.8) and pressing the DOF preview button. The viewfinder will become darker.

bobbyz wrote in post #12121479
Does the VF brightness changes between f2.8 and f1.4? I need to look clearly to see if there is a change.

Mount a f/1.4 lens, set aperture to f/2.8, then press the DOF preview button.

Err...jinx!

smythie wrote in post #12121490
the difference will be two stops. Try setting your lens at an aperture two stops smaller than its widest setting (eg your 1.4 at 2.8) and pressing the DOF preview button. The viewfinder will become darker.

Just did in my room with one lamp, seems like small change than what I thought it would be. I have heard there is a limit above which VF brightness doesn't changes even if you get faster lens, could be wrong.

I can see more change from f2 to f2.8, lot less from f1.4 to f2.0.

A big aperture can also help focusing speed in lower lighting, as AF is done wide-open even if the actual shot is stopped down.

dmnelson wrote in post #12121494
Mount a f/1.4 lens, set aperture to f/2.8, then press the DOF preview button.

Actually it depends on your focusing screen

A lot of focusing screens cant show any difference with a lens faster than f/2.8

As for the above, I generally use my Sigmalux at f/2, primarily because its what i bought it for, and i will RARELY stop it down below f/2.8, Because my 15-85 has IS in those situations

dmnelson wrote in post #12121528
A big aperture can also help focusing speed in lower lighting, as AF is done wide-open even if the actual shot is stopped down.

Not as simple, my 300mm f2.8 IS will focus lot faster than 85mm f1.2. Even 400mm f5.6 focus lot faster than most f1.4 lenses. But I get your point.

KenjiS wrote in post #12121532
A lot of focusing screens cant show any difference with a lens faster than f/2.8

Hmm, good to know. The difference is certainly visible on my 1Ds Mark II, though it's barely perceptible if only stopping down from 1.4 to 1.8, for example.

snyderman wrote in post #12120666
Comment directed at me and it's kind of sticking in my craw, if you know what I mean. The off-the-cuff comment was something like, 'why would you have an f/1.4 lens if you're not intending to shoot wide open with it?'

What am I not getting here? Yeah, I have a couple of f/1.4 lenses and an f/2 lens and rarely if EVER see a need to shoot below f/2.

Is it because I don't do macro or something? Might this be a case of I don't know what I don't know?

dave

Each to their own. An aperture is not the only trait of a lens. Maybe you like it's colour rendition. Or the great bokeh. Maybe you have the fast aperture just in case. Maybe they are upset because you can afford nicer gear then them. Who cares. Do not worry about. Just have fun. It is all we can really do.

Cheers!