FAST LENS=Blurry Backgrounds, Tack-sharp Eyes, Depth-to-die-for…..
FAST LENS=Blurry Backgrounds, Tack-sharp Eyes, Depth-to-die-for…..
What does it mean to have a “Fast Lens”?
So many photographers long to shoot images with that super sharp focus on the subject, falling off quickly into softness and glorious glows in the background. I’ve had a few ask me how to get that look. Well, it is the function of a “fast lens”. But, what, exactly, does that mean?
A FAST lens means it has a very wide aperture, like 1.2 or 1.4, perhaps 1.7 or1.8. That means it can capture images in very little light because the aperture opens up very wide to lets lots of light in. The benefit (or could be seen as a curse) is that when you use a wide open aperture, the elements create a shallow depth of field. (“DOF”) Or some companies call it Depth to Defocus. It means only a short distance is in focus.
Like this image of Kaitlynn: hey eyelashes are incredibly sharp but you can see the far edge of her eyebrow is becoming quite blurry, and so is her ear. You can tell that maybe the only plane that is in focus is about an inch deep- from the tip of her nose to her cheekbones and lips. It’s a lovely look, and very much in vogue for macro, fashion and fine art!
The other effect it creates is called “Bokeh” (pronounce ‘Bo- Kah) which is where lights in the background (out of focus) create orbs of glowing lights! So beautiful!
Typically these lenses are also “Primes”, which means it has one focal length, and not a zoom lens. Maybe it is an 85mm, or a 50mm. To zoom these lenses, you must zoom with your feet…..(ie., move closer). The quality is evident and the ability to shoot in very low light is a wonderful feature. The cost of a lens like this is also more than your typical zoom or lens that may have an aperture or f-stop of 3.5 or 5.6. (which is not considered a ‘fast’ lens at all). This was taken with my “favorite party-night-on-the-town lens”, the Lumix Summilux 15mm f1.7.
For years, I couldn’t justify the cost of a fast prime lens, so I made due with a 2.8 aperture for anything where I wanted that shallow depth of field look. Placing the subject very near the lens certainly increases the depth of field appearance with even 2.8. This SFO bridge shot from Fort Point, was taken with the #Lumix 12-35mm at 2.8
But then I got the Nocticron. [#soinlove!] It is a Leica lens, a prime lens, of 42.5mm with f1.2 aperture. You may wonder why the 42.5?? It is a lens for a Micro 4/3 camera sensor, with an equivalent focal length of 85mm for a full-frame camera. The nice thing is it is easy math (just double the number) to know its equivalent, but the biggest ‘nice thing’ is that it costs a fraction of a lens for a full frame or DSLR! The lens has some beautiful, heavy glass, too, so it is actually one of the heaviest lenses I own, but because it is for a Micro 4/3 Lumix, it is still about a third the weight and cost of a lens for a full-frame camera! For my fashion work, I use it a lot and it gives me clean, crisp, amazing images, allowing me to use a very fast shutter when working with movement! When working with babies in their homes, it allows me to shoot in soft window light and low light areas, perfect for precious moments with baby!
The Nocticron (42.5mm, f1.2), and the Summilux (15mm, 1.7) are two of the VITAL SIX lenses I own for my Lumix G9 system. (see below) They are vital tools that make my job easy and my images beautiful in naturally-lit situations!
Learn more here at LUMIX:
MY ‘VITAL SIX’ LENSES:
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