All lenses have a limit of how much of a scene can all be in focus at one time. When shooting macro photography, you are especially limited of how much depth of field you have because you are extremely close to your subject. The depth of field can be razor thin when shooting at such a close distance. To get around this limitation, you can use a technique called Focus Stacking to increasing the depth of field beyond what your lens is capable of.

But in order to create a focus stacked image, you must first shoot a series of images where the focus plane is moving through your subject. You then take all of those pictures into Photoshop, and blend them into a stack where only the parts that are in focus are included in the final image. Focus stacking allows you to get an incredibly large depth of field.

What you will need

Tripod – You will want to have a sturdy tripod. Because you will be taking multiple pictures from the exact same spot, you want have your camera locked down tight. Try to not have your camera move at all.

Shutter Release (optional) – A remote so you can take your hands off of your camera to prevent camera shake. A remote shutter is not required, you can use a 2-second delay to let the camera stop shaking before it snaps a shot.

Take the Pictures

First set your camera lens to Manual Focus (MF). You want to have full control over where the lens is focusing. If you leave the focus set to auto focus, the camera will focus in all the wrong places and you will end up with a poor final image.

Set your camera to full Manual mode. Because you are taking a series of nearly identical images, you want the exposure to be exactly the same from one picture to the next. Set your camera to manual shutter speed, manual aperture, manual ISO, pick any other white balance besides Auto. The only thing you want changing between all of your shots is the focus.

Beginning with your focus locked onto the closest part of your subject, take your first shot. For my shot, it was the little hairs on the head of a bumble bee and its mandibles. Next I turned the focusing ring to just move the focus away from the lens to get the bees eyes in focus and I took the shot. Next I turned the focusing ring a little bit more to move the focus even further away from the lens.

Keep shooting until you have everything you need in focus. I ended up with about 10 pictures to use in my focus stack. I would have taken one more but the bee decided it was tired of this silly human flashing lights in its face and flew away. I ended with everything in focus except the very tips of her wings. But that is okay, I got close enough where you can see the tips of its wings and that was good enough. She could have flew off 10 seconds earlier and I would have only half a bee in focus. I see it as she stuck around a few seconds longer than she wanted in order to help me get a great portrait of her.

This is the before picture of the amount of depth of field I was working with. Because of the distance I was shooting at, and the aperture I was using, only a little bit of the bees body was in focus at one time. I was shooting with a Canon 7D, with the Venus 60mm f/2.8 Ultra-Macro Lens with 2:1 Magnification. This lens is a completely manual lens that I recently picked up. I was shooting at 1/125 sec, around F8, ISO 400.

Stacking the Photos

First import your pictures onto your computer. I import mine into Lightroom and I find the series of images I want to stack together. Do any edits you need to do now like exposure or curves adjustments. Just make sure you sync those edits to all of the other pictures in your series. You want all of the shots to be identical. Just do not crop the photos at all. You can crop when you are finished building your focus stacked image.

I suggest exporting the pictures in JPEG. Focus stacking works just as well when using JPEG images. You already applied all of your edits and corrected any exposure problems in Lightroom when you were still in the RAW format so exporting in JPEG wont be a problem now.

Open up Photoshop and go up to the File menu, select Scripts, and then select Load Files into Stack…

Using the Load Files into Stack is one of the easiest ways to get a bunch of photos into Photoshop at once. Browse and find the pictures you want to load, and make sure to check the box that says Align Images. Even though you were on a tripod when you took the pictures, Its possible that the tripod may have been bumped, and auto align will double check to see if all lined up and fix any movements.

Select all of the layers by clicking on the top layer, holding the Shift key and selecting the bottom layer. This will select every layer between the top and bottom layers. Only when all the layers are selected will you be able to select the Auto-Blend Layers… option under the Edit menu.

The Auto-Blend Layers tool can either be used to stitched a panorama together, but in this situation, you want to Stack the images on top of each other. I suggest you also check the Seamless Tones and Colors box. You will end up with a much more natural looking image. And now click OK and let the image process.

Once Photoshop finishes processing the image, you will have a layer mask added to all of your layers. These layer masks are masking out anything that is out of focus and keeps everything that is in focus.

The layers are meticulously stitched together keeping the in focus portions, and ignoring the out of focus stuff. It would take an extremely long time to do all of this manually. Photoshop can process it in just a moment and it is impressive how well it works. So start the process and go get yourself a drink of water, it will be done by the time you get back.

The final image shows nearly every bit of the bee in focus. All the way from the mandibles by its mouth, clear back to the wings. The very tips of the wings are not in focus because the bee flew off just before I was going to snap the final shot. But I don’t think it hurts the final image.

I was surprised how easy it was to to create a focus stacked image. I have always known what focus stacking was, but I never really tried it until recently. As long as you give photoshop a decent set of properly shot images, it will take care of the rest and deliver some amazing results. Focus stacking works for all types of shots, not just macro. It can infinitely increase the size of your focusing plane to produce some spectacular landscape photos. Go give it a shot, I plan on using this technique often in the future. It i just another tool in the photography arsenal.

Tips

Go Faster – Move faster in getting my series of shots. Not all subjects will be motionless so the quicker those images are taken to each other, the better. The Bees antennas were moving around between shots so in the final image, I had two sets of antenna in which I had to remove one.

Use Liveview – Liveview allows you to zoom in on your image to check to see if the focus is tack sharp through your subject.

Get Everything In Focus – I failed to get the tips of the bees wings or its antenna completely in focus. I wanted to get the bees body in focus before it flew away, If I had more time, I would have gone back and gotten the rest.