Categories
Planning

How to take photos that are always in focus

How to take photos that are always in focus

If you’re like me, you spent loads of cash to get the best gear, only to find your photos are just as blurry as before. Or worse, you weren’t using your gear correctly. You already have everything you need.

In this video below, I share my manual live view focus technique (starting at 1:20). This method is great for focusing in low light as well.

How to take photos that are always in focus

We’ve come to rely too much on camera technology. Just because your camera says your subject is in focus DOES NOT guarantee it’s as sharp as can be. Even the best cameras can be slightly off when autofocusing.

So if you’re photographing something that’s not moving like landscapes, forget about autofocus, single point af, focus tracking, and all that other mumbo jumbo. Do this instead: put your focus on manual.

3 Easy Steps To Great Manual Focus

    Set your camera to manual focus.

Find out the best way to access manual focus for the make and model of your camera.

Using your camera’s digital zoom, zoom in 100% to what you’d like to focus on. Don’t zoom in with your lens! I demonstrate this technique in the video above.

Use the focus ring on your lens to make your subject as sharp as possible. Then take your shot!

DSLR Pro Tip: Live View Focus

If you own a DSLR camera (mostly Canon or Nikon), you’ll need to enter Live View mode to zoom in with your digital zoom. Next, zoom in 100% with the magnify button – usually a magnifying lens icon.

How to take photos that are always in focus

Mirrorless Camera Pro Tip: Digital Zoom Focus

If you own a mirrorless camera (Sony, Fuji, Panasonic, etc.), there’s no Live Mode. Mirrorless cameras have electronic viewfinders (EVFs) whereas DSLRs have optical viewfinders. You’re always looking at a digital projection with mirrorless cameras, not through the lens itself as you would with an optical viewfinder. To put it simply, mirrorless cameras are 100% live mode cameras.

You do however need to make sure your camera’s digital zoom is at its max setting when focusing. For instance, Sony’s digital zoom starts at 5.9 times magnification but can go up to 11.7 times magnification if you press the zoom (magnifying glass) button. Don’t forget to turn on focus magnifier so the camera will automatically zoom in 5.9 times when you turn the focus ring.

On Fuji cameras you spin the rear command dial to zoom in. You can also turn on Focus Check to have the camera automatically zoom in when you turn the focus ring.

Focus Peaking: Should You Use It?

How to take photos that are always in focus

These days almost every brand of mirrorless camera has focus peaking. According to Sony, Focus Peaking: “enhances the outline of in-focus ranges using a specific color in Manual Focus or Direct Manual Focus shooting. This function allows you to confirm the focus easily.”

That doesn’t mean you should use it though. I prefer to have it turned off. The added focus peaking color actually blocks your view of what’s in focus. So again, you’re relying on your camera’s ability to nail the focus, not your own.

Conclusion

You don’t need expensive gear to take sharp landscape photographs. Whether you own a DSLR or mirrorless camera, manually focus your lens and you’ll never miss a shot again. Don’t underestimate this simple yet highly effective tip. It’s the secret to razor sharp photos.

I wanted to practice photography with flash so turned off the room lights and tried to take a photo but there is a circle that shows in viewfinder when the camera has locked the focus on something, well I couldn’t get that circle to show, meaning it wasn’t able to focus. So as much as I press the shutter button it resists and doesn’t allow me to take a picture. However I remembered that I could have turned on the focus illumination light to help it focus maybe that was my mistake but other than than is there other things I should know about?

Here is what I was trying: I was in Aperture mode, with f 1.8 and ISO 800 . Camera was Nikon D-810 which they say is great for focusing at dark. The flash wasn’t the camera flash, I has just bought a bigger flash that sits on top of camera, one of those.

So in these situation should I for example switch to manual mode?

How to take photos that are always in focus

3 Answers 3

When they say the AF system does well in the dark, that doesn’t mean when it’s pitch black. All AF systems have lower limits, and on your D810 that value is -2 EV at ISO 100. Even if you’re focusing manually, the same parts of the AF system get used to detect whether or not you’re focused.

You have a few choices, most of which involve more light:

  • Focus manually in the dark and squint a lot
  • Turn on the lights and focus manually
  • Use AF with the lights on and lock it in before turning the lights off
  • Enable the AF assist lights on your camera and flash if they have them

If you’re not using the AF assist light, the AF system will report no focus after you turn the room lights off and the shutter release will be inhibited. There’s a setting that bypasses that.

If you were getting enough light for your exposure, but weren’t able to focus, then try manually focusing – usually there is a switch on the lens that will let you do this. On manual focus, your camera will take the picture right when you shoot.

Actually, you said you were using flash – so you want to find a AF-S or AF-Assist mode on your flash – this should pre-fire the flash as your camera is focusing.

With flash, you’ve got a fixed time, so shoot in manual, set your shutter speed to 1/125. Then you’re controlling the aperture and ISO to get the image you want.

Without flash then you have to balance your settings so that you can take the image without camera shake. This won’t solve the camera’s ability to focus, but here’s what I do:

In Aperture mode, you can open up your f-stop to it’s lowest setting, and that will get you fastest speed (lowest shake). However, you’ll probably get camera shake around 1/30 of a second if you’re not on a tripod, so at some point you’ll be bumping up your ISO. The higher your ISO the grainer and more flat your photos are, so this may not be ideal. Personally I’d use shutter priority, set my speed at 1/30 or 1/60, and go from there.

When shooting without flash, use manual in dark areas where you want things darker than what the camera expects. As in, if you want the pictures darker than what the camera is giving you, shoot manual. If you’ve got time to review your shots and adjust, this works great.

If you’re on a tripod, then you can experiment with much slower speeds, meaning you can get lower ISO, and higher f-stop for photos which look better.

How to take photos that are always in focus

In the last post, I discussed how to select an image from the photo library using the Image Picker package in Flutter. It worked great and we were able to display the image in our application.

In this final part, I will demonstrate how you can capture a photo using the phone’s camera and display it on the screen. It is highly recommended that you read the first part because a lot of configuration and permission requests were discussed in the earlier post.

The first step is to install the camera plugin. The camera plugin will allow us to use the physical camera on the device and capture photos. Start by adding camera dependency to the pubspec.yaml file as shown in the implementation below:

Next, we need to update the _showOptions method to take into account when the user selects Take a Picture from Camera option. The implementation is shown below:

The _showCamera method is responsible for getting access to the available cameras and then taking the user to a separate view to preview the photo. The first camera is going to be the back-facing camera.

Currently, the TakePicturePage does not exist. The TakePicturePage will be responsible for allowing the user to capture the photo using their camera. In the next section, you will learn how to show the camera preview to the user and then send the captured photo back to the HomePage so it can be displayed on the screen.

When the user selects the camera option they are taken to the TakePicturePage. The TakePicturePage is going to allow them to preview the picture and then capture on tap of the button.

The TakePicturePage uses the CameraController to take the picture. CameraController is also used to set up and configure the preview. The initialization of the TakePicturePage widget is shown below:

The camera is the required argument in order to create the TakePicturePage widget. TakePicturePage is also a stateful widget and consists of the initState method which is responsible for initializing the camera controller.

The next step is to preview the camera. For this to work you can either run the app on a physical device or Android emulator. Please note that previewing and taking a picture will not work on iOS simulator.

The implementation for previewing the camera view is shown below:

We used the FutureBuilder to evaluate the _intializeCameraControllerFuture and later used the CameraView to display the preview of the camera. If the Future is still resolving then we show a CircularProgressIndicator() instead of the CameraPreview widget.

The result is shown below:

Android uses fake room emulation so users can test out taking pictures using emulators without having to install the app on a real physical device.

Always, always, always make sure to run the app on a physical device before deploying it to the production

The final step is to take the picture. We added a FloatingButton as a second child to our Stack. The button will be responsible for capturing the photo. When the button is tapped, _takePicture method is fired. The implementation of the _takePicture method is shown below:

First, we wait for the _initializeCameraControllerFuture to resolve. Once, the future has been resolved we get the path to the temporary directory where the image will be saved. Finally, we call the takePicture function on the _cameraController instance which takes the picture and saves it to a specific path. After taking the picture we pop the page from the stack and sends back the path by passing it as a second argument to the Navigator.pop method. This means that the caller can now get access to the path and use it to display the recently captured photo.

Back in the HomePage widget we get back the path from the Navigator and set the state as shown below:

Since, we are setting the value of _path inside the setState closure this will cause the build function to get triggered, which in turn will display the captured image. The implementation of the build function is shown below:

The result is shown below:

In this post, you learned how to capture image from the physical device and display it on the page. I encourage you to download the code and run the app on a device and give it a spin.

How do you have both the background and foreground in the image in focus at the same time?

Last week I was attempting a shot where I had the back of a hat in focus and in the distance you could see a mountain. I wanted both in focus, but could either focus on the mountain or the hat. I ended up taking the in-focus shots of both and merging them in Photoshop. While that isn’t difficult I would prefer to shoot the shot as accurate as possible. From what I have read aperture is important in the depth of field but what are the techniques for keeping both the background and foreground in focus?

I am using a Nikon D5100 with a 18-55mm f/3.5-5.6 (standard kit lens) and a 55-200mm f/4.5-5.6.

This question almost answers my question, but I am a bit confused. Can someone explain this a bit differently? Thanks!

How to take photos that are always in focus

3 Answers 3

I think this is mostly answered, but I’ll add some examples.

When a lens is focused at a particular distance, the image will appear sharp from some distance in front of the focus point to some distance behind it. The range from “nearest sharp point” to “most distant sharp point” is called depth of field (DOF).

Here’s a Wikipedia example. The focus point is the “depth of field” text, and the DOF extends approximately from the line below to the line above:

How to take photos that are always in focus

DOF depends on three factors. (That is, three factors you can easily change. DOF also depends on the size of the camera sensor, how large you want to print or display the picture, how closely you look and how critical you are, but I’ll assume that these are constant.)

The factors you can easily change are

Aperture: Smaller aperture gives more DOF.
Example: (All examples for Nikon D5100 or other APS-C 1.5x crop camera.)
55mm f/5.6, focus at 10 feet: DOF range from 9 to 11 feet (2 feet total)
55mm f/22, focus at 10 feet: DOF range from 7 to 18 feet (11 feet total)

Distance: More distance from camera to focus point gives more DOF.
Example:
55mm f/5.6, focus at 10 feet: DOF range 9 – 11 feet (2 feet total)
55mm f/5.6, focus at 20 feet: DOF range 16 – 26 feet (10 feet total)

Focal length: Shorter focal length gives more DOF.
Example:
55mm f/5.6, focus at 10 feet: DOF range 9 – 11 feet
18mm f/5.6, focus at 10 feet: DOF range 5 feet to infinity

So to maximize the depth of field, the basics are

  • Shortest possible focal length
  • Smallest possible aperture (although at very small apertures you run into diffraction blur instead)
  • If possible, increase distance between camera and foreground
  • Focus slightly behind the foreground subject, to exploit the fact that DOF extends some distance in front of the focus point.
  • 18mm f/22, focus at 2 feet: DOF range from 1 to 12 feet
  • 18mm f/22, focus at 10 feet: DOF range from 2 feet to infinity
  • 18mm f/22, focus at infinity (the mountains): DOF range from

So you could have everything from 2 feet to infinity in focus, by focusing at 10 feet.

If you want to go advanced, you could improve DOF slightly by focusing at what’s called the hyperfocal distance. (Although you would need a table or calculator to look it up.)

Focusing at the hyperfocal distance gives the maximum possible depth of field, in this case that’s

  • 18mm f/32, focus at 1.7 feet (hyperfocal distance): DOF range from 0.9 feet to infinity

That’s the best optics can give you. If you need more than that, you’ll have to fake it by taking multiple shots and merging them.

You can find these values from an online DOF calculator like the one ElendilTheTall linked to. Just select your camera (or another camera with the same size sensor, like D5000 in your case) and fill in focal length, f-stop and focus distance.

Note that these DOF values are only approximate: The DOF range is calculated using a definition of “acceptable sharpness” – subjects at the edges of the DOF range will be slightly out of focus, but we might still call them “acceptably sharp” – and what you consider acceptable will probably differ from the standard definition.
You will have to experiment to find your own limits, but a DOF calculator is a good starting point.