Antarctic Peninsula Day 4

Day 4 – February 3 – Perterman Island and Vernadsky Station

This morning we awoke to cold air temperatures, two inches of snow on the deck, heavy overcast skies, and some areas of fog. The ship was heading into the Lemaire Channel, a narrow passage between the Argentine Islands and the Antarctic Peninsula mainland. The temperatures here were at freezing, and the amount of ice floating in the channel was surprising compared to what we had witnessed so far.  Small icebergs, bergy bits (smaller than 5 meters in height) and brash ice (small pieces floating together) littered the passage and the ship just pushed them away; smaller pieces of ice rafted together in the currents and created patterns.  Even with the dark grey skies, the blue ice of the icebergs was surprisingly vivid. At the end of the Lemaire Channel there were many large icebergs in the distance.

The morning stop was Peterman Island, inhabited by colonies of Adelie and Gentoo penguins as well as a small colony of Antarctic shags. The snow here had large areas of greenish or reddish snow; the color due to algae that grows in areas of permanent snow. The landing on a rock shelf was easy, and paths led to Gentoo penguin colonies to the right and left, with the Adelie colony further up the hill on the right.  A path on the left led uphill to an overview of a small inlet that had an accumulation of grounded icebergs or various shapes.

 

The afternoon stop was six miles further South at Vernadsky Station, a Ukrainian research base.  While waiting for our arrival time at the station, we spent time exploring the nearby waters which were filled with icebergs of every shape imaginable. These large icebergs were carved by currents, flipped over as the center of mass changed, and carved again. We never witnessed a large iceberg turn over, but it was easy to imagine how impressive it would be.

The station was originally established at this site on Galindez Island, part of the Argentine Islands chain, as a British facility in 1954 and was sold to the government of Ukraine in 1996 for one pound.  The UK had no further need of the station, and the cost of dismantling the base due to Antarctic agreements would be costly.  Scientists from Ukraine lost access to Antarctic research facilities with the dissolution of the USSR, so it was a win-win situation. The Ukrainian Antarctic Center conducts projects in geomagnetism, seismology, upper atmospheric physics, meteorology, biology, and physiology research. Expanded to house 24 people, and operates the world’s most southern gift shop and public bar serving homemade vodka. One of the scientists conducted a tour of the facility which ended at the gift shop and bar, where we sampled the vodka.

After our visit here, we returned to the ship and started our two day journey across the Drake Passage.  It started off with high seas; I spent most of the time the first day in bed, which was not a loss since the fog was fairly think and the horizon could not be seen until two days later when we approached the Beagle Channel.

Antarctic Peninsula Day 3

Day 3 – February 2 – Orne Harbor and Cuverville Island

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South Side of Orne Harbor

The day started with heavy overcast as we cruised toward Orne Harbor, where a large glacier is the main feature at the end of the harbor and a large hill of exposed rock is on the south opening to the harbor.  This is the location of the Chinstrap Penguin colony we were scheduled to visit. A few chinstraps were in the water near the shelf of rock that served as a landing area, but there were thousands of penguins along the ridge. The path to the ridge was on the other side of the ridge, which we saw when the ship rounded the point on the way to the afternoon landing area. Oceanites reported 1000 chinstrap penguin chicks on the ridge.

Although these small penguins climb this hill (on the other side) perhaps several times a day, I found I was too unsteady on the climb up the hill to make it worth it and decided to stay near the landing area to photograph penguins in the water and on shore, an Antarctic Tern that stayed in the area, and a few landscape images. The zodiac cruise that followed went deeper into the harbor, up to the glacier at the end.  There was a large amount of brash ice here, and several reports from some of the zodiac drivers of whales flipping their fins near the kayaks and zodiacs.  By the time we arrived in the area it was over.  We did see images of the whales approaching the boats as well as some underwater images of the whales swimming by the boat.  There was a report, and later some shared images in a slide show, of a leopard seal playing with its food, a penguin.  We also cruised to the mouth of the bay, following a humpback whale hoping it would breech or take an interest in us. The vista of huge icebergs and nearby 3,500 foot mountains across the Gerlache Strait was spectacular. 

 

Our afternoon landing was on Cuverville Island, a rocky island in the Errera Channel between Rongé Island and the Arctowski Peninsula on the Antarctic Peninsula. The island is an important birding area as the large breeding colony of Gentoo Penguins resides here.  It is the largest Gentoo colony on the Antarctic Peninsula, and the Oceanites counters reported approximately 5,000 Gentoo chicks on the southern part of the island.  To my untrained eye, there seemed to be at least as many penguins nesting on the north end of the beach.

The skies were open overcast with patches of blue sky and the temperature here was warm, just above freezing with no wind so our waterproof coats came off to be more comfortable.  The coats are necessary in the zodiac because the speed of the zodiac causes a wind chill that is surprising for the low speeds involved. One the way from the ship to the beach we stopped to examine a relatively small iceberg that had an interesting shape. The icebergs are shaped by environmental forces; air temperature, wind, water currents.  Only ten percent of floating ice is above the surface, and when the center of mass of the iceberg changes due to erosion of the submerged portion, or a large piece breaks off, the iceberg reorients itself revealing a portion that had been submerged and carved by the ocean currents.

Gentoo penguins were everywhere; large colonies at either end of the beach, on the rocky slopes of the hill, and on the ridges high on the hill.  The rocky ridges are the first to show as the summer approaches, and those that make a nest here are able to lay eggs earlier, and the chicks have a greater chance of survival if the weather is severe during the summer months.  Bringing food up to the chicks on the ridge, adults develop trails of compressed snow that are chest deep.  Often there are two parallel paths, one up and one down. There were great opportunities to photograph penguins on the beach and at either end.  Prior to leaving the beach to cruise around the island, the hearty souls in the group took the opportunity to take an Antarctic plunge off the beach. We finished out visit to Cuverville Island with a cruise around the island where a few spectacular icebergs were found.

 

 

Day 4 – February 3 – Perterman Island and Vernadsky Station

Antarctic Peninsula Day 2

 Day 2 – February 1 – Paradise Bay and Neko Harbour

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The day began with clear skies, flat seas, and reasonably warm weather.  Our morning stop on this day was the Almirante Brown Station, a scientific research station built by the government of Argentina.  The station had been mostly abandoned for a time due to fiscal problems and appeared uninhabited, although there were signs that repairs were being made to some of the buildings. Gentoo penguins were nesting in the areas around the buildings and allowed close observation of the nesting areas along the trail up the hill. I was surprised to find a Sheathbill, a.k.a Antarctic Chicken, a land based bird that is an opportunistic feeder, stealing krill and fish from penguins, eating their eggs and whatever insects they can find.  Surprisingly, we were told they also eat penguin poop.

After enduring the rough weather of the Drake Passage and the previous night’s snow and high winds, the blue skies and reflections of mountains, glaciers and icebergs was a welcome sight.  The views were stunning.  We walked up the trail to the top of one hill to find the trail up another hill.  We probably should have climbed that hill also but the view from even this lower elevation was plenty scenic and in any case, the sooner we returned to the shore, the sooner we would get out in a zodiac to cruise Paradise Bay looking for Antarctic shags (similar to cormorants) , whales and seals.

One of the adventure activities offered on the Vavilov is sea kayaking. There were about a dozen passengers who had signed up for this activity, and this was their first outing.  They had to wear dry suits so that if they tipped over, which they did on purpose this morning, they would be dry and float until their safety zodiac driver could retrieve them. 

We cruised the edge of the bay past a shag colony on the side of a cliff, on our way to cruise the bay looking for whales, seals, and any birds that may be there. This is where we found Sophie, one of the enthusiastic kayak guides; a shag had landed on the bow of her kayak and used it as a platform to search for fish in the water.  It stayed with her for quite some time and eventually she had to quickly paddle away when it went in after a fish.

We found several leopard seals sunning on small icebergs.  I say small, but leopard seals are 9 to 12 feet long, and can weigh up to 1300 pounds, so the chunk of ice needed to carry animal is substantial. We also stopped to observe and photograph Weddell seals.

 

Our afternoon stop was Neko Harbor on Andvord Bay, and to get there we cruised by a small peninsula in the Aguirre Channel where Chile’s Gonzalez Videla Base is located. There are several buildings there but it is now considered inactive.  However, there are fuel stores and supplies in storage for emergency use, or in the event that the base is reactivated in the future.

We landed on a rocky beach with large colonies of Gentoo penguins at either end. The Oceanites census takers reported 2200 Gentoo chicks here.  With so many penguins entering and leaving the water, this was the only site on the trip where I was able to capture penguins porpoising; jumping out of the water to catch a breath as they are swimming underwater. There were many penguin families with two chicks, alternately eating and sleeping, and we observed male penguins collecting stones for their mate’s nest even though it was well past mating season.

The Neko Harbor area was a great place to photograph Gentoo Penguins, but with the clear blue skies and no wind, the scenery was fantastic to view and photograph. With the great light and more floating ice to be found, the occurrence of “blue ice” became more frequent.  Blue ice is created as snow accumulates on the ice caps, the weight of which compresses the layers of snow below to form ice, and as the pressure builds forces the air out of the ice, the size of the ice crystals increases making it dense and clear. Water, and ice for that matter, absorbs red and yellow light resulting in its blue color. The surface of ice and snow will typically reflect the full spectra of light, appearing white, but when light is transmitted through the ice, it will appear blue.  As evening approached, the skies became cloudy with a few gaps that allowed the last of the sun to light small sections of the landscape.

The rough seas were mostly forgotten.

 

Day 3 – February 2 – Orne Harbor and Cuverville Island

Antarctic Peninsula Day 1

Day 1 – January 31 – King George Island

Bellingshausen Station, King George Island

Bellingshausen Station, King George Island

Our first stop, Bellingshausen Station, is a Russian Antarctic research facility at Collins Harbor on King George Island. Adjacent to this set of buildings are research stations operated by Chile and China. One of the South Shetland Islands, the summer temperatures here are relatively warm, with much of the accumulated melting away, and giving opportunity to lichens, mosses and other vegetation to grow. Unfortunately, much of the snow free areas are muddy.  On land, we were allowed to wander around the area, follow one of the expedition staff on a hike along some of the roads, and visit the small Russian Orthodox Church.  There were a few Chinstrap penguins along the beach and it was our first exposure to observe these medium–sized seabirds as they interacted with each other.

One unique activity today was the short run prepared for a group of avid motorcyclists who booked a trip to the Antarctic with the intention of being able to ride a motorcycle on the continent, which will have completed their goal of riding on every continent.  One of the expedition staff photographers took video of each person riding the single motorcycle on the road; documenting the (minimal) environmental impact of the event on the site.

After exploring the immediate area, we boarded a zodiac and cruised along the shoreline and around a point to a Gentoo penguin nesting site on Ardley Island.  This was our first introduction to a breeding colony and it was surprising how extensive an area the nest site covered, and the amount of uphill travel these birds had to travel. Also on board our ship were two volunteers for Oceanites who were tasked to count penguin chicks, as well as nests and chicks of any birds observed, at each of the sites the ship will visit. At this stop they counted about 5000 Gentoo chicks.

Our evening landing was planned to be at Deception Bay, which has a narrow opening in the rim of an extinct volcano. However, due to increased winds with a direction that would make passage into the bay unsafe the captain and expedition leader canceled that visit.  The evening did prove to be energetic with waves crashing into the bow and so cold that snow began to accumulate on the outer decks.

 

Day 2 – February 1 – Paradise Bay and Neko Harbour

Antarctic Peninsula 2013

1024-2859Chris and I cruised the Antarctic Peninsula with her cousin Beth Devlin and her husband David Vandyke. Beth, a veterinarian wanted to see penguin chicks, did some research, and asked if we would like to go along.  We booked the cruise with Polar Cruises, who provided excellent advice and considerable help in making our way to Argentina to board the ship. After a rough start (our first flight was cancelled causing a one day delay and a lot of rescheduling) we arrived in Ushuaia, Argentina to board our ship, the Akademic Sergey Vavilov which was designed for acoustic research by the Russian Academy of Sciences, and converted to a polar adventure ship. The ship is operated by OneOcean Expeditions.  We were pleasantly surprised at the ship and the accommodations, considering the ship was a working research vessel.  The members of the expedition crew were diverse in their areas of expertise, with specialists in birding, wildlife, kayaking, two professional photographers and even a historian.  All had extensive experience in the polar regions and were extremely helpful.  The ship’s Russian crew were friendly and eager to help, even across the English-Russian language barrier.  Most of the crew certainly knew more English than we knew Russian, except for Dave, who got to practice his Russian and learn a few new words from the waitresses.

The cruise of the Antarctic Peninsula starts with a trip through the Beagle Channel and across the Drake Passage, a voyage that typically takes two days.  Unfortunately for us, we were caught in two storms where the captain had to “heave to”, point the ship into the wind and ride out the storm, resulting in taking three days to complete the transit.  We were briefed on the storm conditions, which apparently were a first for this particular itinerary; Beaufort Nine conditions (50 mph winds, 35 foot seas). The expedition crew regularly adjusted the programs and sites to visit based on weather and time available.  After the stormy transit we were blessed with two days of clear skies and flat seas, one day of party cloudy, and the last day of heavy overcast skies.  Our transit of the Drake Passage back to Ushuaia was also stormy the first night but nothing like our trip down; however, the entire return trip was in fog, with no view of the horizon.

Our late arrival at King George Island led the expedition staff to adjust their itinerary since we had one fewer day than normal, but it’s likely not a unique situation. 

The rest of this post will be divided by each day, with images taken at the sites visited. There are links below the gallery thumbnails to each post, and a link at the bottom of each subsequent post to the next.

 

Day 1 – January 31 – King George Island 
Day 2 – February 1 – Paradise Bay and Neko Harbour
Day 3 – February 2 – Orne Harbour and Cuverville Island  
Day 4 – February 3 – Petermann Island and Vernadsky Station

In The Yard — Pink Lady Slippers

 

This spring was a spectacular year for the lady slippers in my back yard.  There was one cluster of 20 flowers, with smaller plants of one to three flowers nearby.  The flowers are located on the edge of the forest, next to a pile of cut logs with a rack of firewood behind it.  Natural lighting can be difficult to deal with as the sun is low on the horizon sending shafts of light through the foliage of the trees.  Occasionally overcast skies provided flat light that reduces or eliminates harsh shadows on the flowers. It was an opportunity to try several techniques capturing these beautiful flowers, and I went out early each morning while the air was cool and still.  Once the sun starts warming the ground, air currents are created and even the slightest breeze results in significant movement in these large flowers on long stems.  I often used a 160 LED lamp to illuminate a single flower. Most images are captured with a Sigma 150mm lens on a Canon 5D Mark II.  I used tripod or beanbag for support and a wireless remote shutter release to avoid any movement during exposure. In addition to single captures of the scene, I made many captures with focus stacking in mind as well sets of images (a series of the same image at all f-stops) for use in teaching programs.  I also made a few images using a 50mm f/1.8 on the Canon 7D.

The first set of images were made by selectively focusing on different parts of the flower, then merging them into one image file using Helicon Focus stacking software.  Last year I had done quite a lot of image taking and analysis in an attempt to understand where focus stacking works and where it doesn’t. The extensive blog posts totaled 30 pages.  Helicon Focus recently had an update and added a new stacking algorithm which I used on a trial basis.  I was satisfied that it performed well on these image and purchased a one-year license ($30) for the Helicon Focus Lite.  I plan to reprocess the images sets I took last year to see if the new algorithm solve some of the problems I described in my posts last year.

 The reason for using  a stacking program is to benefit from an extended depth of field at the subject while shooting at a large aperture to retain the soft out-of-focus (OOF) background.  The images are labeled as a single exposure or number of images stacked, and the f-stop used.

To better see the effect of apertre on depth of field, images of a scene were captured at a various f-stops, and one image was constructed of several captures stacked together. The higher the f-stop (smaller aperture), the greater the definition in the background structure.  As the aperture is opened, the depth of field lessens and the background becomes a pleasant, soft blur. Unfortunately, the wide aperture doesn’t capture much of the flower in sharp detail, which is where focus stacking can be of benefit.  Care must be taken in capturing images for focus stacking to ensure sufficient overlap in the regions of sharpness.  The technique doesn’t always work cleanly, and in some cases there are artifacts that require a lot of editing to correct, if they can be corrected at all.

Birding Cape May, NJ 3-10 May 2012

My wife Chris and I were able to get to Cape May this year, principally to attend a 3-day bird migration workshop conducted by the Cape May Bird Observatory.  We’ve been going to Cape May every year for the last 20 years or so, except for the last three years.  Bird photography here is generally not easy given the vagaries of weather, which affect when the birds migrate through.  This year much of the warbler migration had passed thought a few weeks early.  On top of that, the trees had leafed out considerably, making finding birds difficult, and making photography even more difficult.  I had more luck this year with osprey and other flying birds.  However, there seemed to be an abundance of Prairie Warblers in the area, and I did get a few good images.

I also did a bit of bird flight photography in preparation of a presentation, Birds in Motion, I made at the Photographic Society of Rhode Island.  I was very pleased that I was able to capture a Bluebird in flight with an insect in its beak.  He was bringing it to his chicks in a nest box.

Enjoy the images.

Interview Posted on Deep Green Photography

My friend and award winning photogrpher Greg Basco has posted an interview he conducted with me for his website, Deep Green Photography.  The interview includes some thoughtful questions on how I view my photogrpahy and the tools and techniques I use to make my images. The interview can be viewed HERE.

Inspiring a Poet

One way I share my photography is to make showcase presentations; groups of slides set to music.  I have two shows completed that I have presented at camera clubs and at the NECCC annual conference.  I was asked to show one at the Cortland Place assisted living facility in Greenville, RI for a change of pace from their normal entertainment activities.  The show “Favorite Places, Favorite Images” was well attended and well received.  One resident, a retired first-grade teacher, was so moved by the show she got out of bed at midnight to write this poem. 

Scenes in Couplets
by Francis Dinneen, Cortland Place

We say lovely scenes – not a car, house or steeple.
Just flowers, birds and faraway tiny people.
In the yard we saw Indian Pipes and other fungi.
And butterflies whose colors struck the eye.
Craggy mountains with their ancient folds
And striking deserts – eons old.
Hills and Valleys made a scene.
I even remember a lovely ravine.
Ancient trees so gangly and stark.
How many years since they’d had bark?
There were streams and gulleys and a water fall.
So much beauty – can’t remember it all.
I recall a desert stretching forever.
I heard someone murmur, “Well I never!”
I saw a double rainbow with all six shades.
Glowing through the mist – a colorful sight it made.
Then there were creatures, some of them small.
Little bugs and snakes, can’t recall all.
Next came the lion – mouth open to roar.
Great fun to look at – not to adore!
There was a geyser in old Yellowstone -
Believe me when I say, it doesn’t ‘geys’ alone!
Clouds and sunsets were there for us.
We got them free – no need to fuss.
The musical scores surrounding them all -
There only one phrase – they did us enthrall.
I’m sure to have omitted a scene or two -
Or three or four – possibly more.

It was a marvelous, splendid afternoon.
Will you please, I beg you, come back soon.

 

Focus Stacking — Part 3

What Works, What Doesn’t

To further understand focus stacking and to compare the good, bad and ugly of Photoshop auto-merge, Helicon Focus and potentially other focus stacking software, I set out to capture sets of images to challenge the technique.  I also spent a lot of time attempting to reduce or eliminate the haloing problem on the rattlesnake orchid image stacks.  I tried dividing the image sets into smaller groups for stacking then combining the stacked images into another stack.  That didn’t improve the image at all.  I also tried reversing the order of the images in the stack, which did not improve the image either.  One approach that salvaged the set of image captures was to change the objective for that image; merge the captures of the blossoms at the front of the plant instead of trying to have sharp details from front to back of the orchid. The image on the left is a section of the nine slice stack and the one on the right is a section of the stack of the five slices at the front of the subject.  All of the background objects (the stem and farthest blossoms) are a softly rendered out-of-focus.

 

After photographing flowers, mushrooms, spiders and water drops, I now had 30 sets of image captures made to support my experiments with focus stacking. The first thing I did was to process the same sets of image captures in Helicon Focus software and Photoshop.  In many cases one did a better job of merging the slices than the other, and occasionally neither product was able to cope with the elements in the composition.

Helicon Focus software did much better at combining the in-focus background with the in-focus foreground objects of my first image stack, the orchid from Costa Rica.  However, that’s not to say that all the Helicon Focus composite images were error free.  In fact, new types of errors occurred.  In the Costa Rica orchid image, there were no noticeable halos or misalignments, and the composite images looked good with none of the pinched paper or edge overlap effects displayed in the image processed in Photoshop. One thing to keep in mind is that this image has a sharp foreground object, an out-of-focus background, and the images were taken with the camera and subject motionless.  Also, Helicon Focus provides two processing methods and encourages the use of both to choose the best result.  The image below is the result of Method B.

 

For convenience, I’ll compare a few of the many focus stacks I made from the subjects I photographed.  The comparison of Photoshop and Helicon Focus image stacks is extensive and can be found HERE.

In the photograph of the rattlesnake orchid plant, the halo effects along the stem and the leaves were greatly reduced in Helicon Focus, but other anomalies appeared.  At first glance it appears that Photoshop includes more area in the composite image. However, if the image were cropped to eliminate the mismatch along the edges of the image, it would be very similar to the Helicon Focus images. It is important to try both methods in Helicon Focus; Method A produced a nice soft background and Method B resulted in a mottled background, so method A was clearly the choice for this images set.  There is a pine needle near the base of the large leaf at the back of the plant.  In the Photoshop images it looks normal, but in the Helicon Focus image it appears in pieces.  On review of the separate slices, I discovered I had absentmindedly removed the pine needle half way through the capture of the image slices.  It hadn’t dawned on me to start the image captures from the start.

 

Photoshop ignored the fact that all the images did not contain the pine needle and masked the layers to include the whole pine needle in the image.  To remove it by changing the masks of the separate layers in Photoshop might be complicated, but Helicon Focus includes a retouching tool that made short work of removing the pine needle from the final image.   Another strange error occurs along the lower edge of the image which is very soft in an odd sort of way.  Image 1 below is a corner of the method A result above, and image 2 is after retouching using the Helicon Focus retouching tool.  It took less than a minute to make the changes.

 

The mushroom photo sets provided a challenge for both the products.  In the most difficult set, two clusters of mushrooms spaced an inch or two apart are in the composition and part of the rear cluster is close to the background.  This arrangement provided the opportunity to investigate where the halo artifact appears.  The 25 captures were made at f/14.  Unfortunately I did not take a similar set at a larger aperture for comparison.  Method A worked best of the Helicon Focus options. The entire image is shown at the left and three areas are identified for detailed examination.  The red outline indicates the composition of the second mushroom image described.

The cluster of mushrooms at the bottom of the composition (detail A) was a challenge for both Helicon Focus and Photoshop.  The three mushroom caps overlap and the moss in the background is rendered in focus since the focus slices extend to include the other cluster of mushrooms.  Both have a halo around the edge of the mushrooms that meet the background moss.  Helicon Focus (both methods) has less of a halo, but would require some serious editing to use as a large print.

 

Detail B below shows Photoshop provides a very good composite image of the overlapping mushrooms with nice detail and good separation from the out-of-focus background.  Method A of Helicon Focus shows a halo at the top of the mushroom cap, and the detail is lacking due to the somewhat muddy looking colors of the mushroom cap.

 

Detail C below is a crop that includes parts of three mushroom caps near the background.  Photoshop again performed well with good merging of the detail in the mushroom caps, no haloing, and good selection of the background information. The Helicon Focus stack has significant problems rendering detail in the mushrooms and the background.  Reviewing the twelve captures in this stack reveals that one or two of the captures had some additional brightness, probably due to a break in the clouds at the time of the captures.

 

Helicon Focus did not do well with the first mushroom focus stack but performed much better on other mushroom images taken on the same day under similar conditions.  The camera was moved closer to capture only the top cluster of mushrooms.  Although the aperture remained set at f/14, moving closer reduced the depth of field of each capture.   Helicon Focus Method A (below) did the best at assembling the composite images with very few anomalies, and the background was a nice soft rendering.  Photoshop did very well also but had a few areas (red circle) where the layer selected was not the optimum sharpness.  The locations this happened in this image would have been fairly simple to fix by adding the image with the best detail as a layer to the composite, and mask in the proper sections. Helicon Focus Method B had the worst result with strange green bands and a background that was nearly psychedelic.

 

Another instance where the use of focus stacking has great benefit for me is when I want a foreground subject sharp, and the background softly out-of-focus, as in the example of the spider and web.  I captured six sets of images and Helicon Focus had a difficult time with all of them due to the movement in the spider web, and exacerbated by variations in the lighting.

 

Photoshop aligned and merged the four captures in this stack, and the only anomaly in the image is circled above.  It is a section of out-of-focus web that shows larger than the web in focus and somehow gets chosen as being sharpest.  This was easily corrected by erasing the section of the out-of-focus web from two focus slices then merging.  The misalignment in Helicon Focus was partially solved by aligning the images in the stack with Photoshop, saving each layer as a new image file, then combining them in Helicon Focus.  This process worked well with some of the rattlesnake orchid images, and while Helicon Focus assembled the spider correctly (image not shown), it still had trouble with the spider web in some locations.

At first I was mystified by the haloing effect, but since Photoshop and Helicon Focus were exhibiting the same effect in the same places on the image, it was likely not related to the software processing.  In fact it is an optical issue.  To prove this to myself I set up an experiment with a subject that could be arranged so that one part of the subject overlapped a more distant part.  I chose a branch of berries from a tree growing in my yard.  To avoid some of the problems associated with subject movement or changes in brightness, I set up two analog lights indoors, placed the branch of berries in a clamp, and set the camera on a tripod.  I also used the Helicon Remote software to control the collection of the focus slices.  The closest and farthest points of focus are set in the software, which calculates how many focus steps can be made between the two settings.  The user has a choice to reduce the number of captures, but I collected the maximum; I could always eliminate slices from the stack.  Capturing the images in this way eliminated some of the sensitivities of the Helicon Focus software which are that the slices should be roughly equal in steps, should be the same brightness, and should be aligned perfectly.

When a subject is out-of-focus it appears as an ill-defined projection of the subject.  When the focus point is on a background subject, in this case the stem, the berry is out-of-focus and extends beyond the in-focus berry.  When the focus is on the berry, the stem is out-of focus.  The area adjacent to the edge of the berry near the stem is impossible to capture in sharp focus, or at least without the out-of-focus foreground image overlapping.  The images below were captured using the Helicon Remote acquisition control software with the camera set to an aperture of f8.

 

Neither Helicon Focus nor Photoshop, or any other focus stacking software, have a chance of correctly capturing and merging images of this type due to the optical phenomenon of the out-of-focus foreground subject making it impossible to get in-focus background subjects adjacent to the foreground subject. The examples below are crops (blue outline) of the full frame image above.  The Helicon Focus and Photoshop composite images all fail to render the berry complete, although the Photoshop rendition is clearly closest to complete. Both methods in Helicon Focus appear to have difficulty in selecting the berry parts early in the process select slices that are more out-of-focus than optimum.  They also exhibit significant halo around the berry and below the stem. The fourth image is a copy of the Photoshop image layered with two of the slices that include portions of the berry near the edge and the adjacent one toward the front.  The image requires additional editing on and near the stick, likely layer masks, to completely correct the red color halo on the stick.  Similar editing can be done on the Helicon Focus images using the included Retouching tool although it would most likely require some work using the masking capabilities in Photoshop.

 

There may also be a benefit to shooting at smaller apertures, and more exploration in that direction is needed. The images below are Helicon Focus processed, one set captured at f/2.8 and the other at f/8.  The image comprising slices taken at f/8 are clearly better as expected; the out-of-focus blur should be smaller at a smaller aperture.  For this composition editing the f/8 image would be manageable as the only difficult areas are between the berry and the stick.  For a more complex image, such as the rattlesnake orchid, editing may be very extensive or even impossible.

 

Conclusions

Photoshop and Helicon Focus both have their strengths and weaknesses based on my observations. Shooting for focus stacking requires planning, just as photographing panoramas and multiple images for High Dynamic Range processing require planning.  The images must be captured with the processing method in mind.  For focus stacking, the best results will be had when the camera is on a tripod, the subject does not move, and the lighting is constant.  This pretty much defines an indoor setting.  However, much of nature is outdoors, where the light can be variable and the subject may move even though the camera is rock solid.  While Helicon Focus generally does well at putting the image stacks together, added benefits are the Helicon Remote control of the image capture process and a sophisticated retouching tool. Photoshop provides the ability to align images in the stack that might be offset from others prior to stacking and can handle brightness variations between images in the stack, and I belive I will have some uses for this technique.

Focus Stacking in General 
PROs:  Useful tool to extend range of sharpness in an image.
—— — Useful to isolate subject and allow background to be rendered as soft focus.
CONs:  May not be effective in cases where in-focus foreground objects overlap in-focus background objects.

Photoshop
PROs: Auto-Align corrects misalignments of captures prior to merging.
 —- — Auto-Merge handles variations in color and brightness in captures.
CONs: Manual acquisition of image slices can leave gaps.
—— – Retouching final image by correcting mask layers can be tedious.

Helicon Focus  
PROs: Some control over merging process.
— —-  Two processes provided with adjustments.
—- —- Sophisticated retouching tool.
—– — Helicon Remote control of camera ensures sufficient number of slices captured.
CONs: Does not tolerate misaligned images in the stack.
—- —- Does not tolerate variation of brightness between images in the stack.

General Considerations
———-Use tripod or other stable mount for camera and lens
———-Control subject movement (shoot indoors, block air movement, subject choice)
———-Stable illumination of composition (subject and background)
———-Equal focus steps (use Helicon remote or other computer control of camera)
———-Smallest aperture appropriate for image

 

I haven’t yet decided if I will purchase Helicon Focus, but I will certainly continue to experiment with the free trial, which after 30 days limits the size of images produced and includes some marketing information on the stacked image.  I’ll try additional images of flowers as I’d like to use the technique in my outdoor macro work, and will come up with methods to control illumination and subject movement outdoors.