Hand-Held Focus Stacking

Snow Peak, Mount Monadnock, Marlborough, NH

Using Auto-Focus Points to Hold the Frame

This week I wanted to share a simple technique to obtain multiple (or at least two) images for focus stacking while hand-holding the camera.


Focus Stacking
I have previously discuss in considerable detail the technique of focus stacking to achieve deep depth of field.  This approach
requires multiple images focused at different planes of the scene which are then combined in post processing to achieve sharpness throughout.  A key requirement of the technique is that the images all be framed to match when aligned in the computer.  With sophisticated software, such as Photoshop, the match does not have to be perfect, but typically this is best achieved with the camera locked down on a tripod.  It can be quite challenging to manually vary focus while trying to hand-hold the framing perfectly constant.  This is where my camera's auto focus points can come to the rescue.

I have never been a big fan of auto-focus for my landscape

Hibernation, Pomfret, Vt.  Two focus planes.

photography.  Even as the technology has improved, I tend to prefer to assure sharpness by manually focusing, often on a tripod and, in poor light frequently, using the Live View Screen.  But when I am faced with a scene which contains a discrete foreground and distant background,  I can often get good results with a two image stack, one focused on the foreground detail and the other on the background.  This is the situation where auto-focus can save me the chore of getting out my tripod, if I have it on hand.


Mount Monadnock
Most photographers are familiar with the technique of holding the shutter down half-way to lock focus on a part of the scene and then recomposing for the final shot.  This is most frequently used when focusing a subject that is off center, but the same technique can be used to grab a couple of images for a simple focus stack.  In the example of Mount Monadnock shot from Marlborough, New Hampshire, I locked focus on the detail of the fence and then re framed to include the distant mountain.  The first image caught the fence in clear focus and then without moving the camera I locked focus on mighty Monadnock and shot again.  As I shot the first image I carefully noted the position of the central focus point square to assist in close alignment of the second image.  In more complicated situations, fully sharp focus stacking can require more than two images, but in bright light, when I can stop down, two are often enough to get good results, especially when there are just two discrete planes of interest. 

Canon 5D Mark II Focus points

Mill Ice, Harrisville, New Hampshire
My Canon 5D Mark II has 9 focus points displayed on the screen, but only the central square is a cross sensor, vertical and horizontal, and therefore the most accurate.  When possible I try to use the central point for focus stacking but there are many times when the central point aligns with neither the foreground or background in my desired composition.  Faced with this situation I can usually find one of the other focus points that will provide the coverage I need.  In my image of the frozen mill pond in Harrisville, New Hampshire, I angled the camera down to using the top focus point to lock in the sharpness of the foreground ice and then recomposed.  In my second image, the focus point was in perfect position to catch the iconic Harrisville Public Library. 

Mill Freeze

Using one of the 8 peripheral focus points can reduce the reliability of the auto-focus, especially in dim light or low contrast. To help, I have switched my focus lock from the shutter to a button on the back of the camera that doesn't require continuous pressure to maintain the focus.  In the mill pond image, I could lock the foreground focus with the central point and then switch to the upper point ready for when I refocused on the background.  Not all cameras can switch the focus button. The directions for mine were buried in an obscure corner of my manual, but, with practice, the ability to lock focus without having to hold the shutter down, works well for me in most situations.

Focus Button on Back of the Camera

Ashuelot River, Keene, NH,
Multiple Focus Planes

The trick with this technique is to hold the camera steady as you re-press the shutter and to learn how to move the focus point around the screen.  I have gotten good enough that I will occasionally try to move the focus point within the screen to catch more than just two images for stacking.  The more manipulations I try, the harder it is to maintain the frame, but Photoshop can do some amazing things with auto-alignment.  Still it is about at this time that I grab for the tripod.




The speed and accuracy of auto-focus in modern cameras is amazing and improving all the time.  I still like to use manual focus in many landscape situation but it is important to understand your camera's focusing capabilities and to use them when the time is right.

Jeffrey Newcomer
partridgebrookreflections.com

Read More

Photographing Falling Snow

And Getting Rid of the Blotches

It is a wonderful, but also occasionally painful fact that landscape photography is often at its best when the weather is at its worse.  This is certainly true when it comes to shooting the winter storms.  Whether gently settling or blown by ferocious winter gales, falling snow drops a lovely veil on any winter scene, but capturing the storm imposes a whole new set of opportunities and challenges.  These include both the practical difficulties of managing the cold and wet, and  also dealing with the fact that snow can appear completely differently depending on setting that are chosen in camera.

Practical Problems 
The physical problems include keeping the camera, warm and dry and avoiding or removing the snow flakes that are inevitably attracted to the lens.  Simple preventive measures such as the use of a lens hood and avoiding aiming the camera directly into the flying snow can be very helpful, but in heavy snow I typically shroud my camera under a towel and only uncover the lens and viewfinder when I am ready to shoot.   Despite the best efforts, snow can attach to the lens.  It is important to check regularly and have dry lens cloths available to clear the view.  I have had the experience of taking a long series of images, only to discover that my lens had become blotched somewhere in the middle of the shoot. 

Basic Settings
Shooting falling snow requires a number of decisions about how you want the flakes to be portrayed.  Subtle differences in shutter, aperture and focal length can make a striking difference in the appearance and mood of the image. 

Shutter
Simply stated, long exposures, usually less that 1/100, will show

Central Square Storm 2 Seconds

the snow as streaks, while a quick shutter will catch the snow as individual flakes.  As longer exposures are used there is a point where the individual flakes disappear and what is left is a soft fog which intensifies with greater distance from the lens.  I saw this nicely displayed in my 2-3 second
exposures of the Christmas lights on Keene's Central Square.  The snow was coming down heavily but no falling flakes could be seen.  Of course the correct shutter will depend on how quickly the flakes are falling. often subtle differences in shutter can make a significant difference in the mood of the image.  Check out the tractor and barn comparison below.   Experimentation is always necessary. 

In the Storm, 1/90th

In the Storm, 1/250th

F13, 1/90th

Aperture
A small aperture, with a large depth of field, will include a greater depth of sharp flakes, which will tend to make the storm appear more intense.  A wide aperture will focus attention on a smaller, more intimate selection of flakes and the shallow depth of field can allow the snow to stand out better against the background's soft Bokeh. 

 

f20, 1/100th

1/250, 340mm

Focal Length
The foreshortening effects of telephoto lens' tend to compress deeper selections of snow again giving a more intense feel.  Wide angle lens' give a broader sense of the surrounding but may need heavier snow to capture the full power of the storm. 

 

Enhance Storm Intensity:Long Shutter, Small Aperture & Long Lens
1/6 th, f 16, 105mm

Crank the ISO
Of course in tough weather conditions compromises need to be made. As always, the appropriate setting for each of these parameters is affected by the others.  In the dark of a storm there may not be enough light to combine a fast shutter with a small aperture.  Fortunately we now have the option to crank up the ISO.  Higher  ISO levels invariably result in more noise, but the good news is that there may be very few situations in which high ISO noise is less noticeable than in a blizzard.


Flash
Snow flake will stand out better, especially at night, if they are

Stone Bridge, Flash with Blotches

illuminated by a focused light source, such as a street light or car headlights, but here is probably no better way to stop falling snow dead in its track than to use flash.  Regardless of the  shutter speed the short duration of an electronic flash will freeze any nearby motion.  This effect will dissipate by the inverse square law as distance from the flash increases.  The problem with flash is that it most prominently lights the nearest flake, which are inevitably large and distracting.  With removal of the grotesque blotches (see below) the remaining flakes are more naturally highlighted  The combination of flash and natural light leads to a complex mixture of exposure and color temperature.  Again experimentation is in order.

Large Blotches Removed (See Below)

Ok, that is some of the basics.  Now let me finish with one of my pet peeves about falling snow images.  The Blotch.

 

Curing the Blotches

Blotched Storm

 
 For me "blotches" are the bane of my falling snow images.  You have undoubtedly seen beautiful atmospheric images of snow storms, but here and there are big blotches of white that seem out of place.  These white smudges come from the snow flakes that are close to the lens when the image is captured.  They are invariably out of focus and to me at least, extremely annoying.  Happily there are. number of ways to eliminate the blotch. 

Shade the Lens
 The simplest solution is to shade the lens from nearby flakes.  In the tractor by the barn comparison,  I shot from under a porch roof at Roads End Farm.  Magically, no blotches.  When a roof is not at hand an umbrella or a piece of card board can also help.  Just keep your shade out of the frame.

Central Square, 1/50th

Slow Shutter
The blotches are generally most noticeable at faster shutter speeds. With longer exposures the flakes are streaked and the smudged nearby flakes become less defined. Again the appropriate shutter will be dictated by the speed of snow fall and the size of the flakes.



 

Cloning and  Healing Brush
You knew we would have to get to Photoshop eventually.  Given the random complexity of the snow images, it is comparatively easy to use Cloning or the Healing Brush to replace the blotches.  In newer versions of Photoshop, the Content Aware Fill tool can also correct the scars. The automatic techniques, such as the Healing Brush usually do an amazing job, but occasionally I will use cloning to find a good source that matches the original background.

 
Multiple Image Layers 
My favorite approach to the blotch is to use multiple images.  Since the location of the blotches vary from image to image, I can use one image to patch another.  I pick the best of a series of images and then add the second best in a layer above the first.  After aligning the two images, I mask out the top layer.  I then scan the image and wherever a blotch appears I simply paint with white on the upper layer mask.  This nearly always brings up a section without the blotch. To me this is the most elegant solution, since the uncovered background tends to match that of the lower image. The blotches on the Stone Bridge above were cleaned with this technique.

The great thing about falling snow is that it provides a treasure chest of creative opportunities all within the easy reach to your camera's basic settings.  Now if we can get some snow out of this miserably cold weather, we will be set to go.  Get out there and experiment.

Read More

Getting the Most from Christmas Lights Photography

Finding the Holiday “Sweet Spot”

This is the time of year when every good photographer turns their camera toward the lights that warm our holiday season. This week I completed an article for the New England Photography Guild on shooting Christmas lights. The blog includes a number of tips that I think are especially important when trying to capture the magic of Christmas illuminations. Check it out.  Christmas Lights Photography (to be published 12/23/13)

As always my companion “Getting it Right in the Digital Camera” blog will include some the images that didn’t fit in the NEPG article.
 

 I have never been a great fan of Christmas light photography; 

Lovely Understated Lighting

perhaps because of the tendency of some folks to bury their homes with garish displays that speak more of their egos than the peace and warmth of the holidays. This year I have been giving the lights another chance, looking for more understated beauty and iconic settings, and of course that led me repeatedly to the beautiful and icon Central Square in Keene, New Hampshire. 


 

I have taken hundreds of pictures of Central Square, but the most popular have been those taken during winter with the Christmas decorations and lights. The square has 4 key elements that can be mixed and match in a wide variety of compositions. These include the gazebo, the white church and, during the holidays, the Christmas tree. Oh yes, and the fourth element is the traffic, both human and vehicular, that always has to be accounted for. This year our tree is a bit small, but nicely decorated. I came back to the square 5 times looking for the best combination of light and atmosphere. I think I finally hit on the “sweet spot” earlier this week.

Bare Ground & Dark Skies

 When I started visiting the Square the lights were beautiful, but the ground was bare. I experimented with compositions including all of the elements, the church, the Gazebo and the tree, but later tried other combinations. The first problem was that the brown grass was unattractively barren and did nothing to reflect the lights. I tried to arrange compositions to include as little of the ground as possible, but I needed snow, and that came last weekend.










As soon as the snow had stopped, I was out again, shooting some of my favorite angles around the square. The key to snow photography is to catch it when it is fresh, the "winter wonderland" time when the trees and buildings are still frosted. This is especially true for Christmas lighting. As I discussed in this week's NEPG Blog, the snow on the trees reflects the color of the light best when the snow is close to the bulbs and before the heat of the lamps melts it away. 

The Blue Hour, but No Snow

One of the keys to Christmas light photography is to shoot during the “Blue Hour”, that time just before sunrise or after sunset when the sky retains a lovely blue glow, but does not obscure the illumination. Lighting photographed in the full darkness tends to appear as if floating in space without sense of context with the underlying scaffolding and surrounding, unilluminated structures.

So what is the sweet spot for Christmas lights photography? For me it includes all the important elements; an iconic New England scene, beautiful and not garish lights that complement the locale, cool twilight in the sky and fluffy fresh snow. After last weeks snow, I hit the jack-pot on central square with all of these elements, but there was on thing
missing. 

It was the classic white church at the top of the square. The United Church of Christ was an essential part of many of my compositions, but the flood light which illuminate the facade didn't come on until the darkness had nearly fully descended. I was
missing the "Blue "Hour"! There 

The Sweet Spot

was some reflected light from the gazebo, but even with enhancements in post, it didn't have a natural feel. There was only one thing to do. I called the church and asked them, for one night, to turn the lights on a couple hours early. Everyone was very nice and understanding and after a search for the appropriate people in charge of the switch, the light came on at 2 PM last Tuesday afternoon. The evening featured a snowstorm, but I was able to catch the fully illuminated church, somewhat softened by the falling snow, and the storm provided a fresh frosting on the trees. With the long exposures the snow flakes were not individually visible, but they acted to soften the overall scene, especially with more distant elements, such as the church. As always, it was a hassle photographing in the storm, but I kept my towel over the camera and managed to keep the lens clear. Most importantly, I had my "sweet spot".

Check out my more detailed list of tips on the New England Photography Blog, and get out to enjoy the show before it flies off to the North Pole for another year.

Jeffrey Newcomer
Partridgebrookreflections.com

Read More

Photoshop's Many Disappearing Acts

Finding the Best Way to Skin the Cat : Is there a Bad Way?

Photoshop usually provides more than one way to solve a problem. The fun is to find the easiest and most effective technique, but the newest and flashiest approach is not always the best.

My photography lives and dies with Photoshop. All my pictures pass through the program as they progresses from a flat RAW image to a picture which reflects the brilliance and drama of the scene. Photoshop is a miraculous program and every few years, when the next version arrives, it gets even better . Whenever a new version is announced the debate begins about whether the improvements are worth the expense of the upgrade, but, given the hours that I spend using the program, it always make sense to use the latest version.

What's in an Upgrade?
Over the years, most upgrades have touted a number flashy new features. Not surprisingly, Adobe aggressively markets the flash, anything that looks cool in a two minutes on-line tutorial. In recent years new features have included HDR, Content Aware Fill, Content Aware Move and Puppet Warp. These are all neat tools but have limited usefulness and they never seem to work as well as they appear in the tutorials. For me the real improvements are often much more subtle, and with greater impact on my day to day work flow. Important, recently added, enhancements have included significant improvements to the selection tools, vibrancy control, Shadow and Highlight controls, the magic Auto-Align and Auto-blend tools, and improved cloning tools. These and other practical improvement have made my photo editing much easier, quicker and more precise.

Don't get me wrong, I am an avid geek and I am always looking for excuses to play with the flashy stuff. I occasionally use Content Aware Fill, to help in the process of cleaning up my images, but it is seldom that I a find situation that calls for some of the other more specialized tools. One of the great things about Photoshop is that there is generally more than one way to solve any particular problem. The trick is to find the one that is the simplest and most effective. Sadly, simplest and most effective are seldom the same approach.

An Unnecessary Example (Moving the Branch)
Recently I caught an image of my village of Spofford, New

Snowy Village and Branch

Hampshire shrouded in fresh white just after a storm. This has become one of my favorite locations, not the least because I can literally see it from my home office window. It is easy to catch the scene in all sorts of light. The view only works when the leaves are down, but I enjoy the effect of seeing the village through a screen of bare trees. It adds to the soft and dreamy feel of the images, but I have always struggle with the one large branch that slashes across the church steeple. Because of an intruding house to the left of my position there is no way to "move" the branch by changing my location. I now feel that the branch does not substantially detract from the stately presence of the church, and adds a natural sense of a village nestled in the woods, but I keep wondering how it would look with the distraction removed. Even more significantly I was intrigued with the challenge of finding the best way to remove this prominent and intertwined feature. I have grown to like the branch right where it is, but I still decided to experiment with different techniques to remove it, including pulling out some of the “flash” of Photoshop CS6.

Skinning the Cat

Cloning 
My first approach was to try simple cloning, trying to pull 

Steeple Cloning

detail  from the surroundings to over-paint the branch. What makes the branch so challenging is that it is quite large and obscures a significant portion of the steeple structure. Cloning is relatively simple where the obstruction lies against a largely random pattern, such as the trees, but it becomes much more difficult against the rigid architectural background. Cloning can be a finicky and time-consuming task. Pieces of uncontaminated background need to found to copy over the problem areas. The final result is the complete removal of the branch. With care, patience and time, cloning can do an effective job. It took about 30 minutes to get a clean repair of this complicated image.  Much of the time was spent finding material to clone over the steeple structure.  It would be nice to find a way to simplify that portion of the repair.
 

Branch Cloned

Patch a Clean Steeple

Move to the left

For a second approach, I decided move to the left just far enough to move the branch off the steeple. The house gets in the way of a good, full image, but I selected and pasted the steeple as a separate layer to the original image and then moved it to overlie the difficult to clone structure. The rest of the branch still needed to be cloned but, again this was not a great challenge. Both of these first two approaches remove the branch entirely from the scene, but there is a way to rotate it out of the way while keeping it as a element framing the steeple. Enter the flash.

Steeple Patched

Steeple Patch

Puppet Warping
My final technique used one of the flashiest of the new features 

Web Around Branch

found in the last couple of versions of Photoshop (CS5 & CS6), Puppet Warping.  Puppet Warp allows selected portions of an image to be rotated around defined pivot points. It is often used to adjust the position of a model's arm or leg, sometimes with a rather grotesque effect. This approach is not perfect and still requires some careful cloning, but, in this case, it had the advantage of moving the branch rather than eliminating it all together. I started by selecting most of the branch and then chose the Puppet Warp Tool from the Edit menu. The tool creates a mesh over the selection that works as a framework that can be rotated around pivot points

Branched Moved

placed anywhere in the mesh. In this situation, I placed a pivot point where the branch met the tree and was then able to rotate the branch away from the steeple placing it in a location that nicely framed the spire. The hole left in the image was filled by a combination of Content Aware Fill and cloning, although using the steeple patch from the previous method would have been easier.  This is not the easiest approach but it saved the branch from extinction and, for a tree hugger like me, that is always a big advantage.

Context Aware Fill

Cleaned up with Cloning

This was all great fun, but after it all, I still think I like the picture with the branch untouched. I did this manipulation on a different image than the one that I captured in the midst of a snow storm, but I think I will leave the original picture unchanged. I apologize for rushing through these techniques. There are great tutorials all over the internet that discuss them in exhaustive detail. The point here was to show that Photoshop provides different way to reach the same goal. It is part of the power and fun of this remarkably pliable program. 

Branched Moved





Nice Puppet Warp Tutorial

Jeff Newcomer

partridgebrookreflections.com

Read More