Seeing in the Dark

Using Live View to Get Focus Right in the Digital Camera

There are times when deadlines seem to pile upon each other.


Harrisville, New Hampshire

This is one of those weeks. I am currently completing an article for the May edition New Hampshire To Do Magazine about Harrisville New Hampshire's remarkable efforts to protect their unique mill village. I am also working on my first official article for the New England Photography Guild Blog. I feel very honored to accepted among this talented and tireless group


Sap Gathering Tradition
Stonewall Farm

of photographers who are committed to celebrating the special beauty of our region. My first contribution will be about Route 124, one of the most beautiful roads around Mount Monadnock. Finally, I just finished shooting the Annual Sap Gathering Contest for Stonewall Farm in Keene New Hampshire. It is always great fun, but a tough slog for the horses this year without snow, or even mud to lubricate the skids. With all of this going on, I'm happy to have a quick tip to share on my blog this week





In two recent blogs I discussed stacking multiple images


Pick the desired focus point

with varying focus points to achieve extreme depth of field in the digital darkroom ( Check out : Focus I, Focus II ). I hope that these techniques did not seem too difficult and complex, but for me, and my aging eyes, the biggest challenge of this approach is getting the focus right for each 




Zoom in to focus

of the images in the field. The  viewfinders in the newer digital SLRs have become brighter, but, especially when the scene is dark,  it can still be impossible to focus precisely. Increasingly, in these situations, I have been using my camera's "live view" capability to nail the focus. Many inexpensive point and shoot cameras use the live view on their LCD screens as their primary or sole mode of framing and focusing, but for many DSLRs this is a newer feature growing out of their expanding video capabilities.





A week ago I was shooting deep in the gorge formed by Catsbane


Catsbane Brook Falls

Brook in West Chesterfield New Hampshire. I wanted to bracket my images to get sharp focus from the foreground leaves to the cascading water, but the fading light made it impossible for me to see where I was focusing. By switching to live view I was able to zoom in on the area of desired sharpness for each image. The LCD screen was bright enough to allow easy adjustment of focus and I came home with my images perfectly prepared for stacking in post-processing. I'm sure many of you are already using this simple technique, especially those who are my age, but there are a couple of points to mention. First, it seems obvious that this approach generally requires you to firmly lock down the camera on a tripod. Secondly, and perhaps less obviously, I always switch out of live view after focusing and before I take the shot. Depending on your shooting mode, exposure can change from shot to shot based on the brightness of the portion of the image that has been isolated for focusing. Of course this is not an issue if you are shooting in manual mode.
That's it. This kind of stuff is like the designated hitter in baseball, keeping us old farts shooting long after we should have hung-em up. I apologize to those whose cameras do not have live view capability, but, for you, I have another quick tip. Carry a pocket flashlight to illuminate the scene while focusing.

THERE, now if everyone is happy I have deadlines to meet.

Controlling Perspective in the Digital Darkroom

 Getting It Right in the Digital Camera

Michigan Ave Chicago, Skewed

One of the most common problems in architectural photography is skewed perspective.  When we look up at a tall building our brains process the image projected on our retinas so that we see the structure as expected, with straight vertical walls soaring into the sky, but cameras do not have our marvelously sophisticated cerebral processors. The camera dumbly sees converging vertical lines which usually only become glaringly apparent when the picture comes up on the monitor. Converging vertical lines, often called key-stoning, can also affect landscape photography. Tall trees appear to lean in menacingly when viewed upward from the ground and, although this is often an interesting effect, it does not reflect a natural appearance. Perspective control has been a challenge since the earliest photographic images, and solutions in the field are the same for film and digital imaging. The cheapest approach is to find an elevated view point such as a ladder, building or hillside, or by moving away from the subject, anything to reduce the upward angle of view. With a digital camera the effect may also be reduced by holding the camera above your head, using the LCD for framing. View cameras with independent front and back rise/fall adjustments and Tilt-Shift lens can compensate for these effects in a much more elegant and precise manner, but at a very hefty price. The new Canon Tilt-Shift 24 mm lens costs $2200 at B&H Photo. Happily, for those of us with budgets less that a small industrialized country, the digital darkroom provides some effective and inexpensive solutions. Really, Photoshop is much cheaper than $2200!

As always the process starts in the field by getting it right in the digital camera.  The end result of any required post-processing will be much more natural in appearance if the severity of the original distortion can be minimized by adjusting camera position and angle. It is also important to remember that digital adjustments of perspective inevitably require cropping around the edges of the image. When capturing a picture that will need perspective adjustment it is helpful to pull back on the framing, providing a buffer for the eventual crop. Again this will not produce the best picture "straight from the camera", but it will save a ton of arduous cloning later.

Once you get home, perspective adjustment is actually quite straight forward. The following specific procedure applies for recent versions of Photoshop, but the concepts will be applicable to other photo editors.

Getting Ready

1. First it is important to make the perspective adjustment early in the editing process. If you try to do this after you have applied masked adjustment layers, the masks will no longer match the proportions of the image layer and will have to be redone.
   
   
2. Start by correcting any rotation in the image. Perspective adjustments will be simplified if the horizon starts out flat and any vertical lines in the center of the image are plumb. Check out my blog on an easy way to straighten horizon lines.
   
   
3. To make room for adjustments it is helpful to reduce the size of the image on the screen creating "gray space".  Without this space the selection handles may quickly disappear outside of the image window.
   
   
4. Press (Alt+") to apply a grid to the image. This will help in applying a more precise adjustment.
   
   
5. Create a selection of the entire image (CTRL+A) or "Select All" from the Selection drop down menu.

The Magic

Choose "Perspective" or "Skew"

1. In "Edit" menu >Transform> then choose either "Perspective" or "Skew".
   
   
2. Drag the upper right and left corner handles outward to correct the key-stoning. When the "Perspective" tool is used, pulling one handle causes the other side to move as well. This applies the same adjustment to both sides of the image, but I prefer to use "Skew" in this operation since the handles can be moved separately to more precisely and independently adjust each side.
   
   
3. Press enter when the perspective appears best and Photoshop's rendering will begin.
   
   
   
    
4. When finished press "Ctrl+D" to deselect.
   
   

Finishing Touches
The image can now be cropped to the desired proportions. If the original image was framed too tightly cloning may be necessary to salvage lost pixels on the edges.

　
Of course there is a price to be paid for shoving pixels around in such aggressive ways. The proportions of the components of the image are unavoidably altered especially when more drastic adjusts are required. In the farm picture, the tractor became noticeably squatter in the altered image, but, in the final picture, I was able to minimize the effect by extending the vertical dimension upward using the "Scale" tool.  Unfortunately, when drastic adjustments are required, the areas that are subject to the greatest stretching can begin to loose sharpness.  This is where minimizing the "key-stoning" in the camera can be critical to a good post-processing result.

Loss of sharpness in the
stretched upper region

That's all there is to it. Now, take the money you saved on a tilt-shift lens and buy me dinner. You pick the place.

Star Track Photography

Back Porch Milkyway,  Chesterfield New Hampshire

In the last several weeks I have been exploring star field and star trail photography. It have dabbled in these areas in the past including taking long star exposures on film years ago, but recently my interest has been renewed by a new project. Over the last year or so I have had the wonderful opportunity to work with Rabbit Ear Films, a small local group of dedicated, talented people, on a documentary film about Mount Monadnock. I am a rank amateur at video but have taken the opportunity to learn while contributing in small ways to this exciting project.  Our goal is to produce a feature length documentary, meeting the high broadcast standards of PBS. Leading our group is Steve Hooper a veteran editorial photographer for the Keene Sentinel and Dan White who works with Florentine Film, Ken Burn's production company. My role has largely been to collect high resolution "B Roll" video of views around the mountain. This works well for me since it is largely video versions of the still images that have been a major part of my portfolio. It is the kind of work that the 5D Mark II handles especially well.

Recently I began thinking about using time-lapse techniques to record star fields moving across the iconic profile of Mount Monadnock. I thought it would make a nice addition to the film.  I have experimented at home using an intervalometer and my old Canon 5D.  I decided to dedicate my 5D for time-lapse to spare the shutter on my newer Mark II. Recently Steve Hooper and I spent a clear cold evening recording the stars over Monadnock from the lovely home of friends in Marlborough New Hampshire. Over about 2 hours we record more than 200 images and after processing we were rewarded with about 13 seconds of a dramatic moving star field video. Unfortunately the lower resolution video here does not reflect the impact of the full resolution version.

Canon Intervalometer

A key component for this process is an Intervalometer which is essentially a remote trigger that permits precise control of exposures longer that the Canon's max of 30 seconds. Importantly for star photography the intervalometer also allows the capture of multiple exposures set at any interval desired. In this case the 200+ images were all 20 seconds long and taken every 30 seconds. You can set the parameters and then go get coffee or even better, take a nap. At the end the images can be assembled into a video using a number of different software solutions (I have been using QuickTime). As you might expect there are many important details that make for a spectacular video and I am still learning. I will discuss this in more detail in the future when I have more experience, but today I would like to discuss another use for these images.

Star Track Photography

Back Porch Star Tracks Chesterfield NH
Densely Packed

You have all seen pictures of the night sky taken over minutes to hours which show the stars tracing concentric circles around the north star, my Northern Hemisphere bias is showing. The pictures are a palpable demonstration of the rotating earth, but they also can be quite beautiful especially when the star trails are framed by interesting foreground elements. Years ago, when I experimented with this using film, I opened he shutter on "bulb" and timed long exposures with my watch. The results were great but noise was always a problem. The same long exposures can be captured on digital cameras with or without the use of an intervalometer, but there is also a noise problem with such long exposures on digital sensors.


Over prolonged exposures digital sensors heat up and the result can be increasing amounts of distracting noise. The severity of the problem varies with different cameras but with longer exposures it becomes a issue for them all. The digital solution is to take multiple images and combine them into a single picture using stacking, blending the layers to create a array of smooth continuous arcs. In my examples, I created the star track by using a selection of the images originally collected for the moving star fields. I experimented with the number of images, fewer creating a less densely packed sky as in the tracks over Monadnock. In the tracks over my back porch, more images created a much busier perspective.


The procedure starts with collecting multiple sky images. I hope I don't have to mention that a tripod is a necessity - don't be offended. You want a clear sky without a great deal of light pollution or intrusion of the moon, but some foreground elements can provide pleasant framing and context.

With the camera on manual you can experiment with exposure. Longer exposures will cut down the number of images required and increase the number of visible stars. The nice thing about the multiple-image approach is that, when you get home you can fine tune the final image by adjusting the brightness and the number of

Beaded Star Tracks with 10 Second Pauses
300x

images that you include in the stack. Shooting in RAW would allow the greatest leeway for post processing, but since QuickTime doesn't take RAW images, I use high resolution JPGs. It is generally best to take pictures immediately one after the other to avoid gaps that could result in a dotted line effect.  I was able to use my star field images, which had a 10 second pause between images, without any grossly apparent  gaps, but a close inspection shows that even this short pause leads to noticeable beading at high magnification.



Once home I pull up all of my images in Adobe Bridge;

Edit Single Image in Adobe bridge

I start by editing one representative image, adjusting brightness, contrast and color, and I try to find a balance between sharpness and noise reduction. When I'm happy with the results I save the settings and then load them to all the other images

Load Images Into a Stack of Layers

In Photoshop, from the "Files" drop-down menu, I select "scripts" and then the "Load Files into Stack" option to create a single file with each of the images as a separate layer. The result is a single image file with all the original images as layers in a stack. Because the camera was locked down on the tripod I haven't found it necessary to align the layers. 

Apply "Lighten" Blending Option to each layer

In order to get the stars to shine through all of the layers the blending mode must be changed to "lighten" on each image layer. This blending mode allows anything in a layer which is brighter than the layers above to shine through. This can be done manually, but I have created an action to make the change on each layer with a single click. There are a number of programs available which do this manipulation automatically, but I find it helpful and entertaining to reveal the layers one at a time, watching the arcs build until they reach the a level which seems best. 




Once I am pleased with the blended image, I flatten the file and can

Plane Trails from Boston

then fine tune the, much smaller, image. One inevitable subject for editing are the ubiquitous airplane trails. In the time-lapse videos these flash by like shooting stars, but on star track images they are random streaks across the image. It is of course a matter of taste, but I think it is worth the time to edit out these scars. Of course airplane trails can be reduce by shooting away from busy flight routes and by shooting later at night. Air traffic falls off significantly after midnight.

Star Tracks over Monadnock (Cleaned)
Less Densely Packed

That's about it. Not too complicated, but with impressive and unique results. Just a couple of other technical points. First if you plan to record many images over an extended period of time you should be sure to use a fresh battery. This is especially important when you are out in the cold. Once you have all the settings locked in, switching off the camera's LCD monitor can extend battery life. If you decide to get a intervalometer you will find that the official Manufacturer versions are quite expensive. The Canon intervalometer is $135, but you can get knock-offs for around $30 that look and work the same. My intervalometer came from China, it cost $25 and has worked without any problems.


So get out on the next clear dark evening and give star photography a try.  There is a lot to learn and I feel I am just beginning. As spring arrives it will be much less uncomfortable and we can come home with something truly special.

Showing Off

Finding the Best Places to Exhibit Your Photographs

Brattleboro Vermont Works Bakery Cafe

I never miss an opportunity for self-promotion so this week I would like to talk about what makes a great venue for an exhibition of your work. It is not by accident that I just hung twenty pictures for my March show at the Brattleboro Vermont Works Bakery Cafe, one of the nicest commercial locations in my corner of New England.

Keene New Hampshire Wor

The Works started in Keene New Hampshire and has expanded to six locations across New England. The store in Keene was one of the first places in which I ventured to show my work and over the last few of years I have shown there three times as well as at the Cafes in Portland Maine, Portsmouth New Hampshire and now in Brattleboro. In addition to great food the Works has always been committed to providing a quality venue for local artists. There are many restaurants in our region who allow artists to display there work, but too often it is an afterthought with little if any investment in providing a setting in which the art can be well presented. I have said this before but a romantic candle lite restaurant is about the worst place to show pictures on the walls. The Works Cafes are a happy exception to this rule. Richard French and his staff have invested in sturdy hanging systems and nice lighting to make the art a part of the experience and not just an avoidable distraction.

Morning Mist, Peacham Vermont

So what are the features of a good exhibition venue. Here I am speaking mostly of restaurants, but the criteria are essentially valid in any location. I have seldom found the ideal location but here are some factors to consider as you explore your neighborhood for places to "show the work".

Audience :

Moss Glen Falls, Granville Vermont

It is important to show to people who will appreciate and hopefully buy the work. I apologize for the snobbery, but a nice restaurant is likely to be more productive than the local pizza joint or sports bar and the pictures will be less likely to be sprayed with beer. Where possible it helps to think of your audience when you select pictures for the exhibition.  Glorious autumn foliage is obviously great for an October show, but moody cemetery images are probably not the best choice for a hospital waiting room. Traffic is also important. I once hung my pictures along an isolated back hall of a local church where it was greatly appreciated by several lovely members of the choir who walked by once every Sunday. Finally, and perhaps most importantly, when exhibiting at restaurants, one of my absolute rules is that I don't show where I wouldn't want to eat.

Hang in There:

Over the years I have seen every kind of hanging system,

Hanging Strip at Brattleboro Works

and non-system. In many places the hanging system involves a hammer, some nails and an instruction to "not damage the walls". I have never understood how an owner of an otherwise nicely decorated establishment could allow artists to pound fresh holes in their walls on a monthly basis. Permanent hanging systems are much cheaper than the cost of replastering the walls, they come in all forms and can make a great difference.
They improve the attractiveness of the show and make installation much easier and more secure.

Hanging at the Keene Works

The Works in Brattleboro uses inexpensive wood strips installed about 2/3 up the exhibition walls. The pictures are easily arranged and adjusted hanging from metal hooks. There are much more expensive solutions, but this allows a nice clean and consistent presentation. The Works Cafe in Keene uses a serpentine wood skeleton with hanging screws that, by itself, is a piece of modern art. There are many solutions, but the one important factor is to confirm the system can handle the weight of your pictures

Lighting:

For me lightening is the most important factor in a venue. The one or two people who regularly read my blog know that complaints about inadequate or non-existent lighting are a recurring issue.

Track lighting at the Brattleboro Works

Photography comes alive with good illumination and it dies in the dark. Restaurants often have soft lighting scattered about the tables which either causes hopeless glare or impenetrable gloom. Sadly good lightening is expensive, but when used properly it can make the art a key element of a regularly refreshed experience. At the Works, track lighting is designed to highlight the walls and can be adjusted to maximum effect. Heaven! 

Dump Rake in the Mist, Dummerston Vermont

Timing is Everything:

Lupines, Sugar Hill New Hampshire

As I plan my shows I always pay attention to the calendar. Nobody buys art in January, and it is helpful to select work that either celebrates the current season or anticipates the next.  I try to be in my favorite locations during autumn and the Christmas holiday season, but here is never a bad time to show the work.  The ideal exhibition slots always seem to go early, so it is crucial to plan ahead.  The best time to ask an owner about a future exhibition is when you are taking down the last one.

Security:

Velvet Surf, Pemiquid Light
Missing in Action,

I hate to have to bring this up but, since I did have a picture stolen from a show, I feel it is important to mention. My picture was snatched from an unattended wall in a local mall. After being angry and then a little flattered, I ended up with an appreciation of the importance of having people watching the work. And if you happen to see this picture hanging in someone's home and notice a small crack in the glass at the lower right corner give me or Law and Order a call.


I am writing this as I sip my coffee at a corner table at the Works. Nice place. Wonderful photographs. I never tire of watching people look at my work, so if you are in the area drop by. Unfortunately right now the place is mostly populated by pimply teenagers, awash with raging hormonal angst. Not the best audience. Add that to my list.

Invitation, Hinsdale New Hampshire

Winters Grip, Spofford, New Hampshire

If you can't make it to Brattleboro this month, check out the images on my Brattleboro Works Flickr Set:

Gone to the Vermont Dogs.

Perfect Face
New Hampshire Snow

After two weeks of fairly geeky photoshop blogs I am thrilled to indulge myself with something far less intense. It is important not to get obsessed with the technical aspects of photography and to remember that the most essential element of a great image is a great subject. Fully embracing this concept, this week’s blog is, of course, about my dog Nellie.

Retreat Farm, Brattleboro Vermont

A week ago I was contacted by a client in Vermont to see if I had any dog photographs to use in a planned calendar. The theme is to be "Dogs of Vermont". Of course, I happen to share my life with a dog who is generally acknowledged as the best canine in all of New England, but as I searched my archives, I was amazed to discover that I could find only one picture of Nellie actually taken in Vermont. 

Faced with the perfect subject but unacceptable backgrounds, I had no choice but to throw Nell in the car and head across the Connecticut River. My plan was to photograph Nellie around as many of my favorite, authentically Vermont, locations as I could manage?  Calendar pictures are generally supposed to look like classic representations of seasons they depict. My problem was that, on Friday, I was saddled with "Winter Without Snow Season". Given the uninspiring surroundings my solution was to zoom in on Nellie’s soulful face and include just enough softly focused background to establish location and to provide framing. 

West River, Dummerston Covered Bridge

Newfane Country Store

Nellie is a great model for this kind of work. She almost always
accompanies me on shoots and has learned the importance of staying when told to "stay". Usually the "stay" is intended to keep her out of the shot, but in this case the goal was to fix her to a location while I clicked away. The trick was finding ways to get her to look at me without inducing her to run in my direction, tail wagging, for a touch or a treat. 

More Treats
Newfane Country Store

Nellie’s hair is beautifully soft, but it definitely has a mind of its own. I brought along her favorite brush, but I soon realized that any attempt to impose order on the unruly coat would rob Nell of one of her most endearing qualities. Over a period of a couple of hours I plopped her in front of Stickney Brook Falls, the animals at the Retreat Farm in Brattleboro, the West River and The Dummerston Covered Bridge. We also visited the nice folks at the Country Store in Newfane, which is a warm and pleasantly dog friendly place. 





Nellie did great. She was remarkably patient and irresistibly cute,

Callie Needs a Home, Windham County Humane Society

but it can be difficult to appreciate her superior qualities without photographs of other, "lesser", dogs for comparison. On the way back we stopped at the Windham County Humane Society in Brattleboro. The folks there were happy to have some of their guests photographed and I have to admit the dogs were almost as beguiling as Nellie. Photographing dogs who are anxiously awaiting new homes is a challenge. These animals are generally

Chase is very friendly

thrilled to get out for more human contact. The trick is to get them settled long enough to grab a couple of pictures. They seemed alternately scared of the big intimidating camera eye and insistent on licking it. In the end I got a few nice images which I hope might help support the Societies efforts to find families for these wonderful creatures. I especially want to thank Anna Mefford of the Society who was a great help and showed remarkable patience as I tried to capture these frenetic fuzzy balls of energy. 

SQUIRREL !

I think Nellie had a good time on her photo shoot. I don’t think the experience has spoiled her. Although she nearly emptied my bag of doggy treat rewards, she seems just as excited as ever to root around in the garbage at home. 


Dusting Addendum
 
Thursday night our latest fizzled snow storm left a dusting of white on the hills of southern Vermont. I couldn't resist dragging poor Nellie out for another shoot.  The early sap run provided an additional opportunity for nice backgrounds.  Now I have more work to do.

Focus II, Getting it Right in the Digital Camera

Baker Brook in Newfane Vermont

This week I would like to complete my discussion of controlling depth of field in digital photography with a review of one additional Photoshop technique to manage especially difficult situations. If you are using a recent version of Photoshop, this is for you, if not, you may talk among yourselves.

Rant-Free Blogging

Mount Monadnock, Marlboro New Hampshire

Last week, after a prolonged rant about what it means to get images "right in the digital camera", I finally got around to discussing how digital photography has expanded our options for achieving wide depth of field. Specifically I talked about blending multiple, focus bracketed images. This approach is usually not particularly challenging, especially when Photoshop can do the work of aligning the image layers. It is easiest when the content of the image recedes from the camera uniformly from the bottom to the top of the frame, but the approach begins to fail when there is a more varied range of depth within the same region of the frame, especially up close. In these situations manual adjustment of layer masks can become frustratingly complex. 

Rosaly's Garden Peterborough NH

In my picture from Rosaly's Garden in Peterborough NH, I used three images to capture the full depth of field. The primary foreground element was the flowers, but, I found that, in the same area, the underlying leaves, stalks and grass were further away and were not sharp in the foreground image layer.


Magic of Auto-Blend
In this situation, Photoshop's "Auto-Blend" tool can be a great help. My first step is always to align the focus bracketed image layers using the "Auto-Align" tool found in the edit drop-down menu. Next I highlight all of image layers and run "Auto-Blend". This tool compares all the images and applies layer masks attempting to select the sharpest of the layers for each point on the image.

Auto-Blend Layer Masks
White Exposes the Underlying Layer

This works better with more layers, but I usually start with at least three. After the computer grinds for awhile the results that pop up are generally amazing with great apparent sharpness throughout the image. It is a remarkable piece of computer magic, but, on closer inspection, the results are seldom perfect. Typically there are patches of soft focus scattered throughout the image. It is possible to manually edit the masks to bring out the best focus, but because the process often requires not only revealing the sharp layer but also covering up the overlying soft area, it can become very complicated to get the perfect combination of masked layers.

After Patching

Area of Soft Focus Following Blending

Applying the Patch

Patching Layers (red)

I have found that it is much easier to copy a set of the aligned layers and place this "patching" set above the originals before I run the blending tool on the original layers. I mask out the patching layers so that, after the blend, I can correct any problem spots by simply painting with white on the appropriate patching layer to reveal the sharper pixels. This avoids all the problems of dealing with the complex interactions of blended layer masks below. It still requires some careful editing, but the results are worth the effort.

Wow. I have come to think of this approach as rather simple, but when I try to explain it, I'm not sure even I will be able to figure it out next time. The only way to understand the technique is to try it on appropriate images.  I guess the easiest way to sum this up is that you are creating a separate set of aligned, but unblended layers to use as the source for corrections to the original blended results. This does result in a very large image file with many layers, but once the automatic and manual blending is done, you can flatten the layers and ideally enjoy a lovely image with otherwise impossible depth of field.



I hope these last two posts have opened up some of the potential of the digital darkroom to manage the challenges of controlling depth of field. The only way to master these techniques is to get in there and play with the tools. You have nothing to loose except that fuzzy foreground.

Chesterfield, New Hampshire