Tag Archives: focus stacking

A Couple Composites

I went for another walk last week at Orlando Wetlands Park with Tom M.  It was a pretty morning and in addition to the normal bird suspects, we also saw Soras, Purple Gallinules, and heard reports of Bald Eagles and many Black Crowned Night Herons.

In this post though, I want to discuss compositing.  Wikipedia says:

Compositing is the combining of visual elements from separate sources into single images, often to create the illusion that all those elements are parts of the same scene.”

Multiple exposures are a subset of compositing, and are much easier to produce in today’s world of digital photography.  In addition to creating an illusion, they can be used to show things that are difficult for a camera to capture in a single frame and better show reality.  Examples are panoramas, focus stacking, HDR, etc.

There’s a lovely Pink Trumpet tree on the west side of the main path into the park.  It’s in bloom and that morning the moon was setting behind the tree.  This snap from my iPhone shows how the tree looked against the sky and moon.

Moon behind Pink Trumpet tree
Moon behind Pink Trumpet tree

I wanted to isolate one bloom with the moon and clouds behind it, but the depth of field with my telephoto lens was too shallow to show both in the same frame.  So I made two,  with one focused on the flower and the second on the clouds / moon.  Then in Photoshop it was relatively easy to combine the two frames to show what I wanted.

Moon, clouds, and flowerMoon, clouds, and flower

Here’s a second example:

Ibis flight sequenceIbis flight sequence

This one is from a sequence of a single White Ibis flying by in a little under 2 seconds.  I brought all 25 frames into Photoshop on separate  layers and aligned them.  Then I used the focus select function to mask the birds from each layer into a single composite.  I ended up having to omit every other frame to avoid overlapping birds.

If you’re willing to dive into Photoshop or any other image editing software that offers layers and masking, you can do the same sort of work.  Think about techniques like these when you’re out photographing.  If you capture the source frames you need when you’re out, then when you get back to your computer you can use them to solve problems and enhance your creativity.

Thank you for stopping by and reading my blog. Now, go make some multiple exposure photos!

©2017, Ed Rosack. All rights reserved

 

Olympus and focus bracketing

I’ve written before about computational photography and focus bracketing / stacking.    And if you’re curious, you can find much more info on the web.

Today’s post is inspired by a gift the Olympus Camera Company has just given to owners of their OM-D E-M5 Mark II and E-M1 cameras.  They’ve issued free firmware updates that add new capabilities, one of which is focus bracketing.  Here’s an example image I made while learning about the new features.  I wanted all the orchids to be sharp and the background to stay blurry.

OrchidsOrchid – a focus stacked image processed in Photoshop from 14 frames made with the new focus bracketing feature in the E-M5 Mark II.  Individual frames are at ISO 200, f/4, 1/25 second, 60mm (120mm eq.).

You can read about the firmware updates at this link on the Olympus website.

There are several camera companies providing new features in firmware updates to existing cameras.  The Olympus engineering team is exceedingly clever and seem to really enjoy exploiting their hardware to come up with novel features, many of which are computational in nature.    Focus bracketing is the latest example.  Here are my first thoughts about this mode:

  • Of course, you can focus bracket manually, but having the camera do it for you is a big help.
  • When you frame your composition, leave room to crop.  The stacking process can introduce anomalies at the edges.
  • Your starting focus point should be on the closest area.  The bracketing function will step the focus away from the camera.
  • You control the number of exposures and relative step size.  The step size you use depends on the situation and you’ll have to use trial and error to set it until you gain some experience.  If your step size is too great, it’ll leave blurred areas in the processed image.
  • Set the number of exposures greater than you think you’ll need.  Once you look at them on the computer you can discard any unnecessary ones.  You can get very good control of depth of field and background blur by selecting which frames to use when post processing.
  • Focus bracketing uses the camera’s electronic shutter, so there are some limitations from that (e.g. flickering / banding due to fluorescent lights;  An 8 sec. longest shutter speed limit; others?)
  • As with many kinds of multi-frame computational images, subject or camera motion will introduce artifacts.  Focus bracketing works best for stationary subjects with your camera on a tripod

Here’s another example.  And yes, including this may give you some idea of how old I am – I’m old enough not to care about that.

My engineering school calculator
My engineering school calculator – a focus stacked image processed in Photoshop from 21 frames.  Individual frames are at ISO 200, f/4, 1/40 second, 60mm (120mm eq.).

For comparison purposes, here is a single frame from the series.  You can see the tremendous difference in depth of field.

Testing the new focus bracketing feature in the OMD EM5 MII. It works well - big thumbs up to Olympus for putting out this free firmware update. This is a single frame. It works well - big thumbs up to Olympus for putting out this free firmware update.
My engineering school calculator – single image

I have more focus stacked images in this album on Flickr.

I’m very pleased with how well this works.  Olympus deserves a big thumbs up for putting out this update for free.  Doing things like this can earn a lot of customer loyalty.

Now if we could only combine it in camera with other computational photography tricks:  focus stacking, plus high res mode, plus HDR, plus … maybe next time.

Thanks for stopping by and reading my blog.  Now – go compute some photos!

©2015, Ed Rosack. All rights reserved.

A couple of photo hints and a Gatorland update

It’s been a while since I’ve discussed any photo techniques, so I thought I’d share two hints that you might not have tried recently.  I also wanted to let you know what’s going on at Gatorland now that breeding season is in full swing.

Photo Hints:

#1 – Focus stacking:  I’ve written about this before. You can read the posts here:

Both of those were macro-photography related.  But the technique can also be used for other situations such as landscapes.

Beneath the bridge, by the rocksBeneath the bridge, by the rocks – Parish Park in Titusville, about a half hour before sunrise

I was at Parish Park in Titusville one morning, looking for a new view point and discovered this area where I could place these rocks in the scene as a foreground for the bridge and far shore.  My problem was that without a tilt-shift lens, using the Scheimpflug principle, it’s  hard to get the entire composition in focus.

I decided to make three exposures, changing the focus point in each.  In the first, I focused on the rocks in the foreground, in the second on the nearest portion of the bridge, and the last was on the far shore.  At home, I did some initial processing (the same for all three) and brought them into Photoshop on separate layers.  Then I aligned the layers and manually blended them together using masks.  I could have used Photoshop’s focus stacking capability, but doing this myself with layers gave me more control.  The resulting depth of field is just how I wanted it.  What do you think?

#2 – Fill flash:  I often carry my flash and use it to add fill light or catch lights in eyes.  It helps and doesn’t seem to bother the animals.  I’ve also used fill flash for sunrise or sunset portraits of people.  It can do a good job of balancing the exposure of your subject against a bright background.

When I saw this Tri-colored Heron posing in the bush, I made a few photos.  But then I thought about adding flash.  When I got home, the photos with the flash looked much better.  The bright, ambient sunrise was balanced with the fill flash on the nearby bird.  There’s a better detail in the bird when I used the flash.

Early birdEarly bird – Tri-colored Heron at dawn (ISO 800, f/5.0, 1/320 sec, on camera flash in auto slow sync mode, -1 stop flash exposure compensation).

If you try this, you’ll need to practice a bit before you use it in a pressure situation.  Make sure you know how to adjust exposure compensation (on both the flash and the camera), shutter speed, and aperture to get the best results.  And if your camera has it, try enabling high-speed sync.  This lets you shoot with flash at higher shutter speeds without getting any black bands on your photos (at the expense of a lower light output).

Gatorland Update:

I went by Gatorland again last week.  The Great Egrets continue to breed and their hatched chicks are growing fast.  There are Snowy Egrets and Cormorants on eggs now and I saw  Tri-colored Herons, Anhingas, and Wood Storks gathering nesting material although I didn’t spot their nest or eggs yet.  A few cattle egrets have also arrived and are courting.  And the gators are getting more active too.

Just before I left, I spotted this large turtle there – I’ve never seen one before.  It looks quite intimidating and I wouldn’t want to be too close to it in the water.

Alligator Snapping Turtle (?)Alligator Snapping Turtle

For a better idea of what you can photograph at Gatorland, you can look through my album on Flickr.

Thanks for stopping by and reading my blog. Now – go make some photos!

©2015, Ed Rosack. All rights reserved.

Ponce Inlet and Bulow Creek – changing light

Tom M. suggested we meet at Ponce Inlet for sunrise a week ago.  I readily agreed, since the last time I was there was August 2010.  We met at the park entrance just after it opened and were set up well before sunrise.  Here’s one of my first photos.  It was very nice of them to put up red and green buoy lights for Christmas.  🙂

Sunrise at the inlet
Sunrise at the inlet – I thought the Christmas colored buoy lights added a nice holiday touch

I’m always amazed by how much light can change over a short time.  Here’s an example.

Daybreak departure
Daybreak departure – A fishing boat heads out to sea at sunrise

The physical distance between these first two photos was only a few paces, but the time change made a huge difference.  The first was at 6:32am, f/8, 30 seconds, and ISO 125.  The second was at 7:22am, f/16, 1/60 seconds, and ISO 100.  The amount and quality of light shifted dramatically over 50 minutes (and the sun rays came in for a short time too).

Moral of the story:  If you’re going to get up for a sunrise photo, you may as well get going a bit early – so you can see and photograph the entire show.  I try to arrive at least 30 minutes before sunrise.

I’d been watching large numbers of mostly resting Pelicans, Gulls, Terns, and Skimmers down on the beach.  After sunrise, I moved off the jetty and photographed them for a few minutes.  I was able to get close to this one without disturbing it, and I thought the low, warm light and the shadow behind the bird made an interesting scene.

Caspian Tern and shadow
Caspian Tern and shadow – The bird wasn’t really alone, there were many others close by

When we visited Bulow Plantation several weeks ago, Tom and I were a little disappointed in the light.  Rain and clouds that day made photography a challenge.  Since it was early when we finished at Ponce Inlet, and the weather was so much better – we decided to go back to Bulow.  The light had changed a lot here too.  But over a few weeks instead of 50 minutes.

Bulow Plantation Ruins
Bulow Plantation Ruins – I merged three images with  focus stack in Photoshop to increase depth of field.  The light this time was much better than our last visit.  And our cameras didn’t get wet!

So that was a very fine, final photo op for 2013.  Thanks for stopping by and reading my blog.  Now – go make some photos!

And since this is my last post of the year, Happy New Year!  See you again in 2014!

©2013, Ed Rosack. All rights reserved

Touchscreen Focus Stacking

Focus stacking is a computational photography technique where multiple images at different focus distances are combined to increase depth of field.  This enables much more of a subject to be in focus than with a single exposure.  I’ve written about this before.  Please read that article for background on the methods and software used.

Normally you would set things up and carefully vary the focus or the distance to the subject by very small amounts using a focusing rail or else by very carefully changing the manual focus of your lens.

Knockout rosebud
Knockout Rosebud

For this photo, I wanted to try something a little different.  I placed the rosebud in front of my tripod mounted camera and used the touch screen to control the focus point and trigger the shutter.  I had the self timer on a 2 second delay to prevent any motion due to my touches.  It was a simple matter to point at various portions of the flower until there were enough photos for the depth of field I wanted.  Then I used the focus stacking ability in Photoshop to blend the images together.

I think that a touchscreen is very useful for this type of photography.  What do you think?

Thanks for stopping by and reading my blog. Now – go make some photos!
©2012, Ed Rosack. All rights reserved

Overcoming shallow depth of field

A pair of Great Egrets in the lilly padsA pair of Great Egrets in the Lilly Pads

I was at Viera Wetlands yesterday and came up on this scene.  The pair of birds was about 30 feet away and  I was using a long telephoto lens (Sigma 150 – 500 OS, @ 500mm) and shooting hand held.  To keep my shutter speed high (1/1000 sec), I had my aperture set to f/8.

Under these conditions, the depth of field (DOF) was so shallow (about 6 inches) that I couldn’t get both birds in focus at the same time.  I could have stopped down to f/16, which would increase the DOF to about 12 inches, but that still might not have been enough – and the risk of motion blur would increase when the shutter speed slowed down.

So how can you overcome such shallow depth of field? Here’s how I did it:

  1. Make two exposures, one focused on the front bird and one focused on the rear one.
  2. In Lightroom, do your preliminary adjustments  so the images’ appearance matches as closely as possible.  You want to keep the background around the birds as similar as possible in the two images.
  3. Open both in Photoshop, and move them into a single file as layers.  Put the base image (the one with the front bird in focus) in the background layer.  The top layer then has the rear bird in focus.
  4. Select both layers and use the Edit/Auto-Align Layers to line things up.
  5. Insert a Layer Mask (hide all) on the top layer.
  6. Now you’re all set to paint the in focus rear bird into the image with the front one in focus.  Select the layer mask and use a white brush color to paint the rear bird in.  If you make a mistake or need to back something out you can change your brush color to black to erase the top layer.  You can also play with the brush hardness and opacity to feather things in.
  7. Once you’re happy with the result, flatten the image and make your final adjustments.

“But Ed,” you say “isn’t this cheating?”  It depends.  If you’re a photojournalist reporting on Great Egrets in Viera Wetlands and how close they often come to each other, then yes it might be.  Journalists must meet ethical standards.  On the artistic side, you’re trying to represent what your eyes (which have a greater DOF) or mind sees.  So in this situation it isn’t cheating.  You’re using the tools available to make the image you want.

“But Ed,” you say “this is too much work!”  It depends.  Some images are worth the effort and many are not.  There’s software you can buy to automate this sort of thing for you.  Photoshop can do it too. But the automated software requires very careful set up and in most cases a tripod, and many exposures with small changes in focus for each one.  In this situation, I only needed two photos, one for each bird.  Alignment between the images isn’t critical since I’m only using a small portion of the second one.  So it’s fairly easy to show the pair of Egrets and not be distracted by having one out of focus.

You can see more of my Viera Wetlands photos in this set on Flickr.

For comparison, here’s the original photo straight out of the camera:

Original image, Straight out of the Camera
Original image, Straight out of the Camera

Quite a dramatic change, and for me worth the effort.  What do you think?

©2010, Ed Rosack. All rights reserved.