I've got a photography tip for you in this week's blog; how aperture affects what's in focus on your subject, as well as your in your background. The slice of focus in an image is called "depth-of-field" and you can think of it literally as a vertical slice in your image, front to back, that's in focus. A deep depth-of-field, with much of the image - subject and background - in focus, is called "deep focus". The opposite of that is a shallow depth-of-field with only your subject, or maybe only parts of your subject, in focus. So if you've still got the image of a vertical slice in your head, a deep focus slice would be thicker than a depth-of-field slice.
We pet photographers, actually most all portrait photographers, love shallow a depth-of-field as it creates a nice creamy background, sometimes with bokeh depending on the lighting conditions, and separates the subject from the background. This is especially important if you have a busy background as I do below. When photographing outdoors, I'm often using a very large aperture (so a small number like f/4 or f/2.8) to isolate my subject from the background. When photographing in my Carrollton studio, it's less of an issue because I have complete control of the background so I often photograph at f/8, or even higher, and still get separation of my subject from the background.
I decided the best way to show the difference between deep-focus and shallow depth-of-field was with an actual example, so I headed into my own backyard in Coppell with my border collie Rooney and my trusty 70-200mm lens that I wrote about in a recent post. While I love my job to pieces, Rooney is a little less excited about modeling. If we go into the backyard, he thinks it should only be for a game of Frisbee (I hope you enjoy his expressions of boredom and annoyance throughout the series below).
All the images below were shot at 177mm focal length and I maintained a correct exposure throughout with adjustments of the exposure triangle (aperture or f-stop, shutter speed and ISO).
(click on any image to view full screen)
Backyard Pet Photography Lesson
So here we are in my backyard on a fairly overcast, but oppressively hot and humid summer day. Rooney is excited because he's pretty sure a game of Frisbee will break out at any moment. Why else would we go outside? I started at f/22, a big number, but a small lens opening (yeah, that one's always a head-scratcher - why couldn't they have made that more intuitive - whoever the photography "they" are?).
As you can see, all of Rooney is in focus, including his tail and while the background is a little blurry, you can clearly make out the fence, the stonework of our neighbor's pool, the steps and the cobalt blue planter. The whole thing is kinda jumbled and there's a lot going on. It makes the viewer work harder to enjoy the subject of the image.
Next up is a full stop larger, f/16. You can see that the black vertical lines of the fence are a tiny bit more blurry and Rooney is starting to pant harder as the sun peeked out for a second and it was a like a steam bath outside.
Down one more stop to f/11, the wrought iron fence is starting to blur up nicely and my dog is starting to get annoyed with me. This. is. Boring.
Down one more stop to f/8 and I'm liking where things are heading; we're loosing detail in the background but Rooney is punishing me and refuses to look at the camera. Border collies have a lot of feelings LOL.
I opened up one more full stop again to f/5.6 and now we're getting somewhere. The background is starting to fall away and allowing me to more easily pay attention to Rooney ignoring me :).
Did you know that lenses are not at their most sharp when they're wide open? Every lens has a sweet spot of sharpness and it's usually not when it's wide open. For example, my 70-200mm lens can open to f/2.8 (small number, but BIG opening), but I rarely photograph at that setting for two reasons; 1) it's not it's sharpest there and 2) I typically like the focus plane to include the dog's nose, to his ears and f/2.8 is going to be a pretty thin slice of focus so something will get left out.
This article explains how you can find out where your lens is sharpest. It's a great exercise to learn how to make that expensive gear in your camera bag work for you. The image below is shot at f/4, fairly close to where I normally photograph a single dog to achieve focus from nose to ears and blur out the background. Note the strong stink eye I'm getting now that we've been outside for 5 minutes and not one Frisbee has been thrown.
Wide open at f/2.8, notice that Rooney's nose and ears are just a tad bit soft (soft meaning they're just barely out of sharp focus). It doesn't bother me because his eyes are tack sharp and that's the first place a viewer will always look. We're drawn to faces, and especially eyes. The large aperture really helps to reduce the distracting background; I barely see the vertical lines of the black wrought iron fence anymore and the stone wall, steps and blue planter are mere suggestions of colorful shapes.
I also got a more cooperative model when I said the magic words now that I had my last image for this exercise; "Wanna play Frizzer?" His ears perked up and a smile appeared on his face as if to say "About time Mom!".
Side by Side Comparison
It might be hard to really see the difference that 6 full stops of aperture adjustment delivers by scrolling up and down through this post, so here's a side-by-side comparison of the image taken at f/22 and the one taken at f/2.8. It's the optics in those "fast lenses" (called such because their large aperture capability allows you to use faster shutter speeds to achieve correct exposure so they're a favorite of sports photographers - disc dog anyone?) that make them expensive, but also oh, so worth it when you see how they can melt a busy background away.
All Around The Pet Photography Circle
I love everything having to do with photography and truly enjoy photographing all subjects, but pet photography is my personal love. I love the sessions, I love editing the images and I love delivering prints and albums and watching clients faces light up when they hold a beautiful print of their pet in their hands.
Now let's head on over to the next pet photographer in the circle which is Elaine Tweedy of I Got the Shot Photography, gives you insight into how she focuses on the real personality of the pet at the end of her lens to see her interpretation on this week's topic of deep focus.
Tracy Allard of Penny Whistle Photography is a Certified Professional Photographer with the organization Professional Photographers of America; a designation held by fewer than 2,000 photographers nationwide and a hallmark of consistency, technical skill, artistry and professionalism. Tracy regularly donates her time and talent to several pet rescue organizations and municipal animal shelters in north Texas, you can read more about them here.
Penny Whistle specializes in both on-location and studio photography providing pet, equine, family, couples & engagement and high school senior portraits as well as corporate headshots and commercial photography services in her studio located in historic downtown Carrollton as well as on location in Coppell, Grapevine, Southlake, Flower Mound and surrounding communities in Dallas – Fort Worth, Texas.