Today, we are going to teach you a cool trick of manipulating the depth of field within your photos called Focus Stacking.
As a photographer you are eventually going to run into the problem of trying to create a large depth of field within a photograph but under certain circumstances you are unable to achieve it. The most common situations where this occurs are during Macro photography and Low-light photography.
In Macro photography you may not have a lens that goes to a very high f-stop. Or, you may be able to achieve a high f-stop but it still does not render the whole image in focus. This is where focus stacking saves the day!
In Low-light photography you may want to avoid a long exposure time (slow shutter speed). You may want to freeze the motion in part of the image, like a moving subject, but also keep the depth of field throughout the whole photo without using a flash. Focus stacking allows you to capture large depth of field images in these low-light situations.
So, What is Focus Stacking?
Focus stacking is a trick photographers use to simulate a large depth of field within a photo by taking several photos of the same subject at different focus points. Then, using a program combine these images together into one photo (also known as image stacking).
By using focus stacking you are able to work around the challenge of only being able to acquire shallow depth of field while taking a photograph.
How do I do it? Capturing the Images
- First things first…you must use a very sturdy tripod! The only way to achieve a flawless looking photo is by using a sturdy tripod. You must eliminate all possibility of camera shift while you shoot your images. Two tripods we recommend are Manfrotto 055XPROB Tripod Legs and Manfrotto 410 Junior Head.
- Next, set up your shot. Compose your macro photography or low-light photo as you see fit.
- Choose an aperture and turn the focus ring so that the closest part of the photo (usually the bottom) is in focus.
- Take a snapshot.
- Now, here’s the important part. Slowly turn your focus ring so that the focus of the image slides upward in the photo while at the same time making sure to overlap the out of focus section of the depth of field. This way no softness will be present in the final composite. More closely spaced focusing distances produce sharper images, so its better to take more images than not enough, especially if you have a very short depth of field in your photo. A larger depth of field will require less images to be taken. Just practice this and you will get the hang of how many images you need to take.
Merging the Photos Together
Focus stacking requires a software package to merge your multiple images together.
We recommend these two:
Both software packages do a great job of aligning and merging images.
Personally, I own Adobe Photoshop because it allows me to further manipulate my photos. Helicon Focus is only used for focus stacking.
Here’s how you use Adobe Photoshop to stack your photos.
- Open Photoshop and choose “File > Automate > Photomerge”
- Under Layout select “Collage”
- Under Source Files select “Browse” and choose all of your images for focus stacking.
- At the bottom of the Photomerge window make sure the “Blend Images Together” check box is selected.
- Select “Ok”
Photoshop will now work its magic and produce a final composite of your images. You may see a slight blur on the outside edges of your photo, if so just crop the image.
And there you have it! You’ve now mastered focus stacking and can achieve large depth of field within photos that won’t allow it on scene.