Why Fast Lenses? (Page 3): Focal length, distance to subject and to background is as much a factor for bokeh as aperture. These were taken at F8. Fast lenses in general (primes and...

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

Urnst wrote:

Fast prime and zoom lenses are huge, heavy, and expensive. What with autofocus and high ISOs with digital cameras why is such value put on having a fast lens? Slower can be just as sharp, albeit with a little less bokeh.

Focal length, distance to subject and to background is as much a factor for bokeh as aperture. These were taken at F8. Fast lenses in general (primes and zooms) are better at wider openings that slower lenses. An F2.8 zoom usually gets really good stopped down two stops. That would be F5.6. A fast prime, say F1.4 when stopped down two stops is F2.8. This is a broad statement, but MTF charts seem to support it more often than not.

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miked46 Loc: Winter Springs, Florida

I use mine SIGMA 30mm, f/1.4 for low light and evening street photo's. Especially when I travel

sb Loc: Florida's East Coast

I have never regretted the money spent on a really good, fast lens. Not to say that the cost didn't hurt the budget, but once I started using the lens, my thoughts became: "oh, yeah"...

sirvive Loc: South Louisiana

Another advantage of faster glass is a brighter viewing image esp with optical viewfinders. As for the word "Bokeh", it is misapplied so often that its meaning will be lost to the wave of colloquial usage. Here is a definition from Photographylife.com: Basically, bokeh is the quality of out-of-focus or “blurry” parts of the image rendered by a camera lens – it is NOT the blur itself or the amount of blur in the foreground or the background of a subject. The blur that you are so used to seeing in photography that separates a subject from the background is the result of shallow “depth of field” and is generally simply called “background blur”. Kind of like the current usage of "virtual" everywhere to mean being shown on video. Yeah.. I know.. get a life. :-)

agillot

make you look rich .

George II Loc: Fayetteville, Georgia

CHG_CANON wrote:

If people envy your gear, that's worth something, isn't it?

JohnKTX Loc: Dallas

CHG_CANON wrote:

The surest way to corrupt a novice is to explain the importance of professional grade equipment.

I will never forget shooting with my first professional body. Once I connected to the computer and saw how sharp - and how many more images were in focus, I knew I was done with my older camera.

martin muller

Speaking of envy.....

https://overgaard.dk/leica-50mm-Noctilux-M-ASPH-f-095.html

long article, be sure to scroll all the way through it.

imagemeister Loc: mid east Florida

CHG_CANON wrote:

Given you have all the answers, why are you asking the questions?

In addition, Faster lenses allow better AF - especially in lower light ....Someonne posted this same question about a week ago ! ?
.

neillaubenthal

CHG_CANON wrote:

Consider listening to the successful photographers when they talk about the equipment they use.

This from somebody who thinks generating gear envy is an important reason to buy something.

nervous2 Loc: Provo, Utah

martin muller wrote:

Speaking of envy.....

https://overgaard.dk/leica-50mm-Noctilux-M-ASPH-f-095.html

long article, be sure to scroll all the way through it.

This article resulted in some serious gear envy.

CHG_CANON Loc: the Windy City

When you ask creative people how they did it, they'll feel a little bit guilty because they didn't really do it, they just have a better camera than you.

lamiaceae Loc: San Luis Obispo County, CA

Urnst wrote:

Fast prime and zoom lenses are huge, heavy, and expensive. What with autofocus and high ISOs with digital cameras why is such value put on having a fast lens? Slower can be just as sharp, albeit with a little less bokeh.

Is this the same post still going from a day or two ago or another one with the same question?

selmslie Loc: Fernandina Beach, FL, USA

Gene51 wrote:

Focal length, distance to subject and to background is as much a factor for bokeh as aperture. These were taken at F8. Fast lenses in general (primes and zooms) are better at wider openings that slower lenses. ...

These were all taken with the same zoom lens at 500 or 600mm and f/8. It's not likely you had a choice of another lens with a maximum aperture faster than f/5.

The question here is about prime lenses. The difference is more apparent in low light wide open. But it takes a lot of careful pixel peeping and review of MTF curves to tell the difference between a 50mm f/1.2 when set to f/4 vs. a 50mm f/2 set to f/4. The DOF is the same although the quality of the bokeh might be different, if anyone cares.

joer Loc: Colorado/Illinois

Urnst wrote:

Fast prime and zoom lenses are huge, heavy, and expensive. What with autofocus and high ISOs with digital cameras why is such value put on having a fast lens? Slower can be just as sharp, albeit with a little less bokeh.

Fast lenses are more flexible under a variety of lighting conditions. Yes slow lenses can be as sharp and even sharper in good light. Fast lenses gather more light and focus quicker under most lighting.

I mostly shoot birds with a 5.6 zoom and a 1.8 prime. In good light the zoom is outstanding, at dawn and dusk it is almost worthless.

You can get good bokeh with slow lenses as well. The controlling factors are aperture, camera to subject distance, subject to background distance, and focal length.

Fast lenses are worth every penny if you need them.