Guide to Getting Everything Focused with your DSLR Camera
Getting everything in focus is not a problem with the DSLR or mirrorless camera, but rather a limitation of your lens and its relationship to the size of the sensor. The conventional way to increase depth-of-field is to stop down, or close, the aperture by using a larger f-stop number. But there are other ways to consider. Let’s look.
Whether you shoot portraits, landscapes, products, architecture, or anything else you will benefit greatly from knowing the techniques of getting everything in focus or, more importantly, everything you want acceptably sharp.
Getting everything in focus is simply mastering depth of field and knowing the limits of what’s acceptably sharp in different situations a photographer finds themselves. The first challenge to accomplish everything in focus is to conquer the depth of field scale, whether it’s on the lens, digitally available in-camera, or available in apps for your phone.
You can have the specifics of f/stop, focus distance, lens, or focal length setting on zoom and know exactly what range will be acceptably sharp. My choice is the phone app that removes all the questions.
Earlier, starting during the film days the lenses had a usable scale that easily showed the range of acceptable sharpness at all settings once the subject was focused. Over the years this has gotten smaller and smaller and on many lenses it is non-existent. Fujifilm takes the prize for moving that on-the-lens feature to the digital display of the camera. Yeah, Fuji!
So that takes us to my favorite, the phone app. My choice is Depth of Field Calculator by Essence Computing Ltd. I can tell it my camera body, the lens I’m using, the f/stop I prefer, and the distance that I’m focused and it will calculate where the sharpness will begin. Then past the subject to the distant point where the sharpness fades away to blur.
Remember, larger f/numbers signify smaller openings. Stopping down decreases the size of the diaphragm opening which makes the depth of field greater. Our goal today of getting everything in focus is a product of this major function of our camera – Depth of Field. Depth of Field (DoF) is something photographers aim for to make their images look more professional. That is – when professional norms require a maximum depth of field.
What’s the Difference between Focused and Acceptably Sharp
The two terms are used interchangeably to mean the same thing. Sharp, focused, acceptably sharp. But, to clarify, if I’m photographing a subject that is 10 feet away and my depth of field shows that from 5 feet to 15 feet will be acceptably sharp.
The only thing focused on is the 10-foot distance. The range from 5 to 15 feet is not in focus BUT the human eye goes to work for us and communicates to the brain – FOCUSED. So it’s all focused–not really. It’s sharp–yes from 5 to 15 feet.
How Getting Everything Sharp is Very Heavily a Discussion of the Specific Uses of Depth of Field
Learn Depth of Field. It’s very important when you’re shooting something like landscapes, where you want everything sharp, but it’s also equally important when you’re shooting things like product shots where you want something to stand out. How getting everything in focus is often just a matter of using Depth of Field in different ways. DoF is what determines whether or not things are in focus or soft, so it comes down to learning to calculate.
|Full-Frame Lens||Start Sharpness (feet)||Focus Distance (feet)||End Sharpness (feet)||Hyperfocal Distance (feet)||F-Stop|
What is The magic of hyperfocal distance
As Wikipedia says – The hyperfocal distance is the closest distance at which a lens can be focused while keeping objects at infinity acceptably sharp. When the lens is focused at this distance, all objects at distances from half of the hyperfocal distance out to infinity will be acceptably sharp.
Depth of field is a range of sharpness from a close distance to a far distance with your subject somewhere in the middle. Or, as in my architectural photography it’s total, everything, is in that range. When the far distance bumps into the distance known as infinity, magic happens. Suddenly you have sharpness at a point closer than the subject and it goes and goes forever.
As an example, in my architecture work, I’ve done my homework. With my 20mm lens on my full-frame Nikon, I pre-focus to 6.2 feet. I measure it with a tape measure. I did this before leaving for the shoots. At f7.1, my depth of field starts 3 feet from the camera and extends to infinity. That covers my architectural photography
|Lens for Full Frame||F-Stop||Start Sharpness (feet)||Focus Distance (feet)||Hyperfocal Distance (feet)|
Pick the Best Lens for Depth of Field
Depth of field can be modified by changing the aperture, focal length, and distance from your subject. The Depth of field helps photographers control how sharp or blurry their scene will be. A lot of people talk about DoF but it’s all about hyperfocal distance. The magic of Hyperfocal Distance will help anyone get the maximum range of sharpness when needed. You’ll notice from the above tables that the depth of field becomes less with the longer lenses or a zoom set at longer focal lengths. When one is to be in a situation pushing the limits of DoF, plan to use the widest lens possible.
You’re about to shoot a large group. You would normally go for the 50mm, but the group will take up 4 rows and will be pushing the ability to keep everyone sharp. Consider the 35mm to add to your depth of field potential. Check by estimating the numbers in the Depth of Field Calculator.
While checking about lens selection on keeping everything in focus let’s look at the longer lenses and their very limited DoF. You’ll see the limiting numbers in the table above for 85mm and 135mm lenses. It’s difficult for me to imagine a situation in which the numbers would be helpful. The lenses from mid to longer will also not offer much in solving our “everything in focus” challenge. Conversely, these lenses are regularly used because of their limited DoF.
Back Up a Bit for Better DoF
It’s the simplest of the variables but it’s quite effective. Doing product photography for catalogs and the shots come up, one after another. It’s laid out like all the other shots but takes a slight bit more space front to back. The lighting is all good and powerful. The first shot is made and some fringing of an edge is not acceptably sharp. The aperture is closed as much as possible, the flashes are as powerful as they can muster. What can we do? Just back up. The shot stays all the same but it is just a foot farther away and all is sharp. Yehaa! In things far beyond product photography, the same Back-Up technique can help you too.
Need to Mention Focus Stacking
My article today is all about making things sharp with the camera. Well, you need to know about another technique and how some images you may have seen are sharp very close to the camera and sharp throughout.
Think of a landscape with a sizable stone in the foreground. It’s sharp but shouldn’t be. At least, not in reality! I have used this technique in-studio product photography but I won’t bore you with that. Back to the landscape in our mind’s eye. With the camera locked down on a tripod, multiple images are captured with the focus changing from close to distant between shots.
In post-production, my preference is PhotoShop, the images (from 3 to 6) are combined as layers and the resulting photograph is sharp beyond the normal limits.
So, Do I Focus On My Subject?
If you have a subject as in portraiture or sports that may be the best way to start. If your subject is a range of distances like architectural interiors or landscape, consider focusing on the hyperfocal distance. Once set, your focus and sharpness will cover from a distance closer than you may have thought to infinity. Get the hyperfocal distance from the Depth of Field Calculator.
Let’s finish up!
The Ultimate Guide to Getting Everything in Focus with your DSLR Camera is a blog post that aims to enlighten photographers about different ways of getting everything sharp. I recommend reading the article and trying out some or all of these techniques for yourself! You’ll find the tips we’ve provided helpful, especially if you’re looking for creative new ideas on how to improve your photography skills. Happy shooting!