Exercising More Control When Taking Photographs
When we approach a scene of interest to take a picture we look for what composition can be included in the frame and maybe what the lighting is doing to the scene. In most instances the camera is automatic and handles all the technical details. Those actions can best be described as recognizing an interesting scene and photographing it, but there is more to photography than that. While the camera (be it film based, DSLR or cellphone) is designed to quickly do that job, often automatically, but it usually has a lot of additional capabilities. It has a number of tools that the photographer can employ to further interpret the scene.
While there are a number of cameras that are automated to just point and shoot, most better cameras (cellphones too) have additional controls; the shutter speed which specifically determines how sharp the image is when there is motion involved (either in the scene itself or with the hand holding the camera) and the aperture which is the lenses area that controls how much light gets in through the lens during the shutters opening.
Shutter Speed is the measurement of how long a shutter is open in taking a photograph. To minimize problems involving motion that create blur in the image you can set faster shutter speeds that can reach 1/1000th of a second or even faster. In very low light, shutters can stay open 1 second or even longer to get enough light to resolve the image. In cameras there are a series of shutter speeds with each step a doubling of the speed from the previous step. Typically they are 1 second, ½ second ¼, 1/8, 1/16, 1/30, 1/60, 1/125, 1/250, 1/500th of a second.
Aperture size or f-stop technically is a ratio of the focal length of the lens to the iris diameter that is controlling the amount of light and is expressed as a fraction. Think of the letter f as the numerator over the denominator number where the higher the denominator number the smaller the fraction and it looks like this f/ 1.4 where f/1.4 lets in twice as much light as f/2.8. The most common whole progression being f /1.4 , f /2.8, f /5.6, f /11, f/ 22 with some cameras also having half stops like f/16. Besides controlling the amount of light getting through the lens the f-stop also controls depth of field or how much of the depth through a scene is in good focus.
Exposure or equivalents are called reciprocity. It’s the concept that combinations of shutter speed and f stops allow exactly the same amount of light into the camera when taking a picture. f/5.6 at 1/125th of a second is the same amount of light as f/11 at 1/60th of a second. The slower shutter speeds allow the photographer to set smaller apertures that create a greater depth of field. The selection is always a compromise between motion blur and reduced depth in focus.
Playing around with shutter speeds and different f stops is the best way to appreciating what you can accomplish. Sometimes an image has more impact with deliberate motion blur. Like tracking a fast moving object with the camera while clicking the shutter at the same time will often provide great pictures where to moving object is in focus while the background shows motion blur. Setting faster shutter speeds also provides for smaller depth of field and that is a great way of focusing attention on a specific area in the scene.
To make use of these features in a digital camera or your cellphone requires that you understand how controlling shutter speed and aperture works in your device. Check the manual or do a device specific internet search and start playing with those controls.
Upping your iPhone game
Controlling focus and exposure separately. The problem with accomplishing that trick is that the iPhone sets both exposure and focus with a single tap. If you tap on your foreground subject and it’s dark, you can end up over-exposing the photo. The easiest way to solve that problem, is to install a better camera app and there are a number available – these include Camera+ ($2) and Top Camera ($3). Using either of these apps, you can tap separately to focus and specify where to set the exposure. The end result: You no longer have to live with under- or over-exposed photos just because you chose to set a specific focus point.
There are also other apps that allow you to change an image after it’s taken. There’s FocusTwist that shoots a short video and then shows you a still photo derived from the length of video. There’s also AfterFocus ($1). Open a photo or take one, and then outline the areas that you want to be in sharp focus. The app then blurs everything else for you, giving you a convincing shot with simulated depth of field.
Lock the focus without using an app on you iPhone. Instead of a tap to set only exposure you can lock the focus on the iPhone with a tap and hold on any spot on the screen for a few seconds when you see a yellow box flash around your finger. Remove your finger and you’ll see the message “AE/AF Lock” on the screen. Until you take the photo, the focus and exposure will remain fixed till you tap the shutter release.
Apps for Android users.
Open Camera is a compact camera app for Android cellphones and tablets. It is free with no in-app ads. This Android app has different focus modes, scene modes, auto-stabilizer, HD video recording, handy remote controls, configurable volume keys, geotagging of photos and videos, support for an external microphone, HDR, dynamic range optimization mode, small file size, etc. and it’s open-source.
Google Camera comes installed on all Pixel devices but the Android community, has managed to make Google Camera app available on other Android devices. Making things like Pixel portrait mode, HDR+, and more plus the Pixel 4 camera’s Astrophotography feature, which enables users to capture great shots in the dark. GCAM apps are ported by third-party developers, so you may find lags and bugs in the download.
Adobe Photoshop Camera is good for taking a lot of selfies as the app comes with a ton of camera filters and effects. The filters can be applied before or after you shoot the picture, and some are remarkable and the app has intelligent AI that recognizes the subject in the picture and applies filters with real precision. It also has post-editing tools that change brightness, contrast, saturation and a magic wand tool that can remove sharp shadows and deep black areas. Unfortunately it does not allow for manual selection of shutter speed, exposure, focus, and is supported only on a few Android devices.
In closing, I had a number of people that challenged me with projects designed to train my eye to see and take better photographs. In the next section I will offer some of those examples to help improve your picture taking.
Available now, our guide to Taking Better Pictures, featuring three sections published on this website in convenient pdf format. Download your free copy by clicking here.
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