Advantages of fast lenses (Page 2): Generally speaking faster lenses acquire focus faster on a subject and are faster focusing in general in comparison to slower lenses. Plus the out...

billnikon Loc: Pennsylvania/Ohio/Florida/Maui/Oregon/Vermont

rb61 wrote:

Coming from 40+ years of film, should I still be obsessed with fast lenses? I liked them for easy focusing (MF). Fast lenses became more important as I aged.

Do current autofocus lenses gain any advantage from faster lenses?

Thanks

Generally speaking faster lenses acquire focus faster on a subject and are faster focusing in general in comparison to slower lenses. Plus the out of focus thingie.

Notorious T.O.D. Loc: Harrisburg, North Carolina

Canon 1 series used to have a number of optional focusing screens you could change in and out. But I think the number has been reduced with the latest 1Dx2. Maybe they just stopped being sold and used.

Jeffcs wrote:

Not sure if it would be posible but! For those of aging wonder if manufacturers could incorporate a split image focusing screen
That said
I prefer as fast glass as possible for several reasons
Generally the quality of a fast lens better built
Better lens coatings
Generally sharper edge to edge
Better boca wide open
And yes faster more light equals
Lower ISO
Easer focusing
Just to point out a couple things

CHG_CANON Loc: the Windy City

Beauty is everywhere when you have the best equipment.

jeep_daddy Loc: Prescott AZ

TriX wrote:

Yes - Lower ISO, shallower DOF to isolate subjects, faster auto focusing....

joer Loc: Colorado/Illinois

rb61 wrote:

Coming from 40+ years of film, should I still be obsessed with fast lenses? I liked them for easy focusing (MF). Fast lenses became more important as I aged.

Do current autofocus lenses gain any advantage from faster lenses?

Thanks

The answer is yes, focus speed and low light focus may improve, but its not all good. They are bigger, heavier and make focusing more critical. There is more than one way to defocus the back round. IMHO bokeh is is different than back ground blur and highly over rated. Did I mention cost?

Keep in mind the difference between f1.4 and f2 is equivalent ISO 100 vs 200. Most current cameras can easily go to ISO 3200 and even beyond.

ELNikkor

My 50mm f2 Nikkor "H" lens is still my favorite. It looks and feels just right on my FM2. The glass is recessed so I never use a lens protecting filter, the "f2" aperture is a nice, round number, (none of this "1.7, 1.8" marketing foolishness!), and f2 is plenty fast enough for fast focusing in low light. I do have a 50mm f1.4 Nikkor, but the f2 H lens is still my favorite.

dmc Loc: Montgomery, AL

Generally speaking....would a prime 2.8 focus faster than a prime 4.0 if the 2.8 was set at 4.0 ?

CHG_CANON Loc: the Windy City

dmc wrote:

Generally speaking....would a prime 2.8 focus faster than a prime 4.0 if the 2.8 was set at 4.0 ?

The phrasing of your question does not reflect how lenses and cameras actually work. The camera focuses with the aperture wide-open for that lens. The aperture is then closed to the specified smaller value only when the shutter is released.

MountainDave

I think every photographer should have at least one big aperture lens for the shallow DOF if nothing else. One of my favorites is the Canon 135 f/2L. Even though its been out over 20 years, it's still one of Canon's sharpest lenses. The AF is not as quick as some newer lenses but I find it to be very accurate and consistent even in poor light which is more important than speed in my book. Women often complain that it is "too sharp!" Haha. It's also fairly light for an L lens and excellent used ones can be bought for 600. or so. A true bargain IMO.

LWW Loc: Banana Republic of America

dmc wrote:

Generally speaking....would a prime 2.8 focus faster than a prime 4.0 if the 2.8 was set at 4.0 ?

Yes. The body always meters/focuses wide open.

TriX Loc: Raleigh, NC

MountainDave wrote:

I think every photographer should have at least on... (show quote)

👍👍 An excellent lens. And with a Canon MKII or MKIII 1.4x extender, you have a quick 190+mm f2.8 lens that is actually sharper than the 70-200 f2.8L at 200 mm and a whole lot lighter.

photoman022 Loc: Manchester CT USA

There is a distinction between a "fast lens" and "autofocus". My Tamron f/2.8 is a fast lens that also autofocuses. The advantage of autofocus (for those of us who are older and have bifocals) is that we can have nicely focused photos! It is often hit or miss when I manual focus with my any of my lenses. The exception to problems of manual focus is when I use live view, which I don't like doing anyway!

damage98 Loc: Tampa FL

CHG_CANON wrote:

Beauty is everywhere when you have the best equipment.

This is soooo true. I can take pictures of tree branches and bark, leaves and grass with my A74iv and Zeiss Batis lenses, and they are beautiful, with so much color and contrast and a special something that I truly cherish. It may sound trite, but gear does matter, in my case, a lot. I am taking photos as a hobbyist, purely for my own enjoyment, and if I am going to make pictures, I want them to make me smile.

Notorious T.O.D. Loc: Harrisburg, North Carolina

Fast lens refers to the large aperture which lets in more light in the same time. Autofocus is related to focus, Auto or Manual. But lenses with larger aperture will generally focus faster than smaller aperture because focusing occurs at the widest aperture. There are some exceptions such as the Canon 85mm f/1.2 which focuses a little slower than the f/1.4 or f/1.8 85mm lenses. The mass being moved can impact focus speed as can the auto focus drive and body being used.

photoman022 wrote:

There is a distinction between a "fast lens" and "autofocus". My Tamron f/2.8 is a fast lens that also autofocuses. The advantage of autofocus (for those of us who are older and have bifocals) is that we can have nicely focused photos! It is often hit or miss when I manual focus with my any of my lenses. The exception to problems of manual focus is when I use live view, which I don't like doing anyway!

CHG_CANON Loc: the Windy City

Without the best tools, we're only as good as everyone else.