Motivation (this page prepared by Mike Douglas)
This page describes a day trip to a cloud forest (Yungas vegetation) north of Cochabamba, Bolivia. It also includes a few photos of an ascent via taxi later that day to Cerro San Pedro, a large hill that is surrounded by the city of Cochabamba. This hill has a number of interesting cacti found upon it; the area receives only about 300mm (12 inches) of rainfall on average.
The Yungas trip was part of a workshop on photography for biologists – the in-class part of the workshop was taught on a Tuesday and the field trip was scheduled for the following Saturday. This workshop was part of the 10th Congress of Latin American Biology Students (XCLECBO) Because of travel complications associated with a Bolivian Judicial election, some students could not stay for the field trip and some students who had hoped to take the workshop (traveling from Santa Cruz via bus, could not make the workshop in time because of road blockages due to strikes.
The travel was arranged via a small bus, with the main destination being a Yungas cloud forest dirt road that had essentially zero traffic on it. We were able to walk several miles along the road and the students were free to photograph whatever subjects they wished. Birdwatching was also carried out by most individuals. All photos on this page, unless otherwise noted , were taken by Mike Douglas.
We first start by describing the route to the cloud forest road.
The figures below, taken from Google Earth, show the main road that connects Cochabamba to the lower-evelations to the north (and eventually Santa Cruz de la Sierra). Fig 1 shows that dramatic change in vegetation (from brown to green) as one proceeds north. The highest elevation on the road is about 12000 ft, the conditions quickly become moremoist as one descend towards the north.
The bus driver stopped at a site that was known to the students; we walked along a dirt road for about 3 hours. This road had zero traffic on it. The road was approximately level, being cut into a steep slope, with the elevation being about 9200 ft.
Google Earth view of the Cochabamba area including the moist Yungas to the north. The circled region indicates the location of the Yungas road we walked along. Some GPS positions that were marked along the way are also shown. Click on this image (and others below) for a larger view.
Elevation and relief of the same area as above. Reddish areas are lower in elevation, silvery are higher.
Annual mean cloud frequency for the same area showing the very cloudy moist region evident in the visible image. The whiter the pixels the more frequent the cloudiness. The darker areas are over Cochabamba and to the south.
A closer view of the Yungas trail area and the mean annual cloud frequency. Whiter areas have more cloudiness. In general canyons have less cloudiness than mountain ridges and slopes.
Google Earth view of the Yungas road (enclosed by ellipse). Two GPS positions are also indicated. We walked about 3-5 km on this road over a 3+ hr period. A treeless flat area area was at the top of the slope – this was about 10,200 ft
Photos along the Yungas road
As the objective of the trip to the Yungas was (officially) to practice photography of natural history subjects I will describe the photos that were taken with this in mind. That is, I will explain why I took a photo, and whether it was (in my opinion) successful or not. This is the sort of self-critiquing that a photographer should do – if no one else is around to provide such critiquing.
My personal interest was to photograph epiphytes, tree ferns, the general forest environment (what distinguishes the Yungas from lower elevational forests for example) and whatever animals I came across. I was not focused on bird photography, and though I brought my 300mm lens, given the overcast conditions and nature of most birds in tropical forests – small and fast moving, I didn’t anticipate much success. I focused on macro photography opportunities and general forest shots. For this type of photography I use most often a 40-150mm telephoto zoom and a 12-40mm wider-angle zoom. Close-up shots were with a 60mm macro. All lenses were Olympus “pro-series” lenses. I use Olympus mirrorless cameras (OMD-EM1) now because of 1) their lighter weight (both camera body and lenses) compared with Nikon series DSLR cameras (that I have but rarely use now), 2) better image stabilization (through the Olympus camera body), 3) folding rear viewscreen is essential for low-level photography (my Nikons (D7100, D300s) don’t have – though newer ones do) and 4) I like the image quality more than the Nikon’s. These are my opinions, yours may differ.
This is the interior of our bus, rented for the trip. This is actually during the return – we were somewhat tired. But such bus travels – especially where there is space and everyone is part of the same group, can be useful to discuss many subjects. Developing personal contacts is a key part of any scientific conference or similar activity. The photo just documents this important aspect of the trip. It is a bit too dark, but I could have brightened this up in Aperture (or other software).
Documenting participants in the activity
To show the activity involved, one needs to photograph the participants involved in their activity. This is best done when they are not aware of them being the subject of the photograph! A telephone lens helps in this – you can be a good distance away from the people being photographed, so more “natural” poses are shown. Below are a few examples of where this worked – and where it didn’t… See the individual photos for a discussion.
Photo shows that cell phone cameras can be used to take pictures of biological subjects … Some problems include the “antenna” (branch) that protrudes from the cell phone and the hands overexposed … esta foto muestra que las cámaras de los teléfonos celulares se pueden usar para tomar fotos de sujetos biológicos … Algunos problemas incluyen la “antena” (rama) que sobresale del teléfono celular y las manos sobreexpuestas …
a tolerable photo – showing everyone looking for a bird somewhere to the right … una foto tolerable – mostrando a todos en busca de un pájaro en algún lugar a la derecha …
A not very good photo – Rosario (in front) points out an insect in her hand, but the person behind (Andrea Soliz – the organizer of the tour) is looking at me – even though I use a telephoto lens … una foto no muy buena – Rosario (al frente) señala un insecto en su mano, pero la persona detrás (Andrea Soliz – la organizadora de la gira) me está mirando a mi – a pesar de que utilize un teleobjetivo …
A forced march … to keep up with the leaders? The photo shows the conditions of humid (fog) and humid along the road … una marcha forzada … para mantenerse al día con los líderes? La foto muestra las condiciones de húmeda (niebla) y la húmedas a lo largo de la carretera …
This photo documents the strategy of taking the photo from a perspective closer to the surface, both for a better perspective and to stabilize the camera in low light conditions. Esta foto documenta la estrategia de tomar la foto desde una perspectiva mas cerca de la superficie, tanto para una mejor perspectiva como para estabilizar la cámara en condiciones de poca luz.
the group dispersed along the way … in fact sometimes I was alone and could not see the people in front or behind me. El grupo se dispersa a lo largo del camino … de hecho a veces estaba solo y no podía ver a las personas delante o detrás de mí.
This photo highlights fog conditions, which do not prevent photography. esto resalta las condiciones de niebla, que no impiden la fotografía.
Is this a way to get a more stable photography platform, or are they just resting? esta es una forma de obtener una plataforma de fotografía más estable, ¿o simplemente están descansando?
Discussion about some aspect of interest – maybe trying to identify a bird using the field guide … discusión sobre algún aspecto de interés – tal vez tratando de identificar un pájaro utilizando la guía de campo …
Looking for that elusive bird En busca de un pájaro fugaz …
A “successful” representation of the group activity. The subjects are focused, without realizing that they are being photographed … Una representación “exitosa” de la actividad grupal. Los sujetos están enfocados, sin darse cuenta de que están siendo fotografiados …
Let’s consider one photo and some possible crops to it. Below is the original photo. It isn’t ideal – the person on the left, taking a photo – has a distracting background of two individuals behind his camera. I should have waited until these people had walked farther on – out of view. But the photo opportunity might have been missed. Actually, I probably didn’t even notice the people in the background. The photo has a positive aspect in that it shows the road climbing and disappearing into the fog. But the crop is too tight – I should have allowed more space to show the road.
Fig 4. The original photo.
Consider a crop of the image above (Fig. 5). Here we are just focusing on the individuals, not the surroundings. This photo might be used to emphasize the differing field clothes worn by the participants. Long pants, hats and backpacks being common (though not universally used). And everyone has boots.
Fig 5 Focus on the people – what story does this tell?
Now consider a possible crop (Fig 6). Here only the lower legs and boots are evident. Such a photo could be used to emphasize that for such a field excursion – boots and long pants are required. Such a photo might be used, for example, in a presentation to beginning biology students on how to dress for the field. No flip-flops, sandals, sneakers, or high heels!
Fig 6. Just the feet and lower legs… what story does this tell?
Here we show some landscape photos along the Yungas road and discuss what works best. Three images are shown in Fig 7. Which do you like best? Least? See the caption for each photo for a discussion.
A common problem is tropical forest photos is shown in the image below. I took this shooting across at the slope:
300mm telephoto shot of Yungas forest in sunlight.
There is sunlight and the result is harsh shadows and uniform “greenness”. Scale is not apparent, and the photo isn’t close enough to clearly make out the epiphytes.
Below are three photos that try to depict the environment of the Yungas forest. Which one do you like the most? The least? See my comments in the tabs for each image.
What is the subject here? I don’t like the hill – too symmetric and centered. ¿Cuál es el tema aquí? No me gusta la colina, demasiado simétrica y centrada.
I like this photo because of the cloud in background and the tree/epiphyte detail in the foreground. Landscape mode useful for powerpoint slide. The upward slope of the foreground vegetation from left to right is also better than having it horizontal. Me gusta esta foto debido a la nube en el fondo y al árbol / epífita en primer plano. Modo de paisaje útil parael formato de powerpoint. La pendiente ascendente de la vegetación de primer plano de izquierda a derecha también es mejor que tenerla horizontal.
This image/crop is useful for vertical format. More detail of trees and epiphytes, but less landscape content. Esta imagen / recorte es útil para el formato vertical. Más detalles de árboles y epífitas, pero menos contenido paisajístico.
Compare this photo with the next one. They are not exactly the same (a tripod would have allowed the same framing), but the main difference is in the light and the fog. Which do you prefer? Why?
I assume you agree that this image has a more distracting background… in essence the fog eliminates distracting background – as well as adding an ambience of misty/foggy that characterizes the Yungas…
Now consider the two photos below. They are taken from similar locations, only with different zoom settings on the lense and with different compositions. Which photo do you like more? What is the subject here – if this is in the “landscape” category?
The subject here is the road cutting through the Yungas forest and the damage to the vegetation on the side of the road. El tema aquí es el camino que atraviesa el bosque de Yungas y el daño a la vegetación en el lado de la carretera..
This is a closer view with less road. The main point of these photos is to show the impact on putting a road through slope forest. There is a “dead zone” that supports some plants (colonizers such a bamboo), but many others are killed or cannot withstand the sunlight or dessication (the brown plants). This makes for easier birdwatching, but perhaps of birds that frequent “gaps”… Esta es una vista más cercana con menos camino. El objetivo principal de estas fotos es mostrar el impacto de poner un camino a través del bosque de laderas. Hay una “zona muerta” que soporta algunas plantas (colonizadores como el bambú), pero muchas otras mueren o no pueden resistir la luz del sol o la desecación (las plantas marrones). Esto facilita la observación de aves, pero tal vez de aves que frecuentan “zonas perturbadas” …
What does this photo show?
This shows the secondary growth in an opening – in part due to the road maintenance. Unfortunately, this is the type of tropical forest photo that is easiest to take – and very misleading since it shows disturbance or “gap” flora, not primary forest. It tends to be hard to take photos of a forest from within the forest! The primary forest is farther back. Of course, on steep slopes there are occasional landslides that produce similar disturbance. See the image below.
Looking up at a recent landslide – a typical disturbance on steep slopes of the Yungas… The photo’s perspective isn’t ideal – it would have been better to be looking across at the landslide.
A photo I like, that show the ambience of the hike, albeit not pristine is the following:
nice mix of people, forest ambience etc… whatever you want to make of it.
Below are two images, with slightly different crops. Which one would you select if space in a publication allowed only one of them to be used (this is almost always the case)?
version 1 – a wider view that shows the forest and trees – as well as tree ferns.
version 2 – a narrower view that shows three stages of tree fern development (smaller plants in the foreground and a taller, more mature plant in the background (out-of-focus but still sufficient to identify it as a tree fern).
Some of the plants
One of the few applications of a long telephoto in a tropical forest (besides bird photography) is to take photos of epiphytes – these might be high in trees. Here is one
A flowering bromeliad, taken with a 300mm lens. This is still a crop from the original image. The ply thing tolerable about the image is that we are looking across at the plant – rather than looking up. Shooting across at epiphytes is much easier on steeply sloping hillsides!
from the Yungas hike – it is one of the relatively few tank bromeliads that I saw along the route. This is a crop from the original image.
Flowers should not be a large part of the overall Yungas biomass at any time of the year, but some interesting flowers were present. Below are some of the ones I noticed – and attempted to photograph. I show different versions of some of the flowers to make points about composition or lighting. The details are in the captions to each image.
A monocot flower – a pair of fingers to control the flower’s movement in the dim light of the Yungas……….Una flor de monocotiledónea: un par de dedos para controlar el movimiento de la flor en la tenue luz de los Yungas
This flower had nice details on the inner corolla………Esta flor tenía buenos detalles en la parte interior de la corola
which of the following three images is best? they are all similar but differ in composition slightly and in focus…………..¿Cuál de las siguientes tres imágenes es la mejor? todas son similares pero difieren ligeramente en su composición y en el enfoque.
this is an orchid (that was later “collected”. Which of the three photos shows the flowers best? …the plant best?……..esta es una orquídea (que luego fue “colectada”. ¿Cuál de las tres fotos muestra mejor las flores? … ¿o muestra mejor la planta?
version 2 orchid
version 3 orchid. This is a flash photo, notice the darker background as the light drops off in intensity…………..versión 3 orquídea. Esta es una foto con flash, observe el fondo más oscuro a medida que la luz disminuye en intensidad
this flower was “inaccessible” so a telephoto was used. Plus, this is a crop of the original image, so the overally quality is only “fair”………esta flor era “inaccesible” por lo que se utilizó un telefoto. Además, este es un recorte de la imagen original, por lo que la calidad general es solo “promedio” …
the flower (flash, with macro lens) of one of the Begonias……….la flor (flash, con lente macro) de una de las Begonias
there were two species of Begonia (or at least varieties) of along the road. They differed in the color of their flowers (not usually an indicator of important differences) and in their leaves………..había dos especies de Begonia (o al menos variedades) a lo largo del camino. Difieren en el color de sus flores (generalmente no es un indicador de diferencias importantes) y en sus hojas.
Don’t know what this was… Note that part of the flower is in sharp focus, as are parts of the leaves, but the depth-of-field was very shallow so much of the plant and flower was out-of-focus. Compromise due to low-light levels. A tripod with Helicon-focus type procedure would have given better results – if there was no wind………No sé qué fue esto … Tenga en cuenta que parte de la flor está enfocada, al igual que las partes de las hojas, pero la profundidad de campo era muy poco profunda, por lo que gran parte de la planta y la flor estaban fuera de foco. Compromiso debido a niveles bajos de luz. Un trípode con procedimiento de tipo Helicon-focus habría dado mejores resultados, si no hubiera viento.
this fruit was at a stop near the lake, not along the Yungas trail. Flash photo with relatively good depth of field. A Ribes?……..esta fruta estaba cerca de la parada cerca del lago, no a lo largo del camino de Yungas. Foto con flash con una profundidad de campo relativamente buena. Género Ribes?
Bamboo is a so-called pioneer plant – it establishes itself in disturbed areas such as landslides, fire burns etc. Thus, it was common along the Yungas road we walked. There are many species, most in Asia but some in South America. The bamboo in Bolivia can be summarized here. I tried photographing the bamboo in different aspects, trying to show some of its interesting characteristics.
compare the next six bamboo images – they show the leaves and branches. Which ones do you like? Which ones are poorly composed? This one here was nice sunlight on the stem and the background is out-of focus………..compara las siguientes seis imágenes de bambú: muestran las hojas y las ramas. ¿Cuales te gustan? ¿Cuáles son ejemplos de una pobre composición? Esta fue una agradable luz en el tallo y el fondo está enfocado.
the colors between the foreground and background are too close – and the bamboo branch is hard to distinguish from the background………..los colores entre el primer plano y el fondo están demasiado cerca, y la rama de bambú es difícil de distinguir del fondo.
the fog here provides a background that separates the bamboo from the background. But the branch itself is not very exciting……….la niebla aquí proporciona un fondo que separa el bambú del fondo. Pero la rama sola no es muy interesante.
a bamboo branch – a bit too close to the background……….una rama de bambú, demasiado cerca del fondo
a grayscale version of this bamboo branch in the fog……….una versión en escala de grises de esta rama de bambú en la niebla
bamboo branch and fog – with the tree in the background providing an idea of the fog density………..rama de bambú y niebla – con el árbol en el fondo que proporciona una idea de la densidad de la niebla.
interesting branching of the bamboo……….interesantes ramas del bambú
a new bamboo shoot, starting from a branch. However the tip of this shoot is not in focus – an almost fatal error……….un nuevo brote de bambú, comenzando desde una rama. Sin embargo, la punta de este brote no está enfocada, un error casi fatal …
this photo of the new bamboo leaves shows guttation – excess water leaving the leaf tips………..esta foto de las nuevas hojas de bambú muestra gutación: exceso de agua que sale de las puntas de las hojas …
Tree ferns have been interesting to me for a long time – they signal your presence in some kind of forest characterized by high humidity and usually clouds. Photographing tree ferns is sometimes difficult because they are often best seen in disturbed areas, where surrounding plants don’t block your view of them. But then you end up photographing “disturbed landscapes”. This was no different along the Yungas road, where good views of the ferns were possible – but only in disturbed areas!
Anyone wishing to identify the tree ferns we saw might first start with this online guide.
“standard” tree fern photo – only good aspect is the presence of fog to highlight the typical environmental conditions of tree ferns
another image of tree fern and trees in the fog
three phases of a tree fern are shown here – young plants in the foreground and an older plant (out-of-focus) in the background. Although out-of-focus the adult tree is still easily identifiable as a tree fern.
do you prefer this image or the next one as the best example of the growing shoot of a tree fern?
compare with previous image
this is same subject (but slightly different view) as previous image – but cropped slightly differently and the saturation and vibrancy have been enhanced. Does it look better or worse than the previous image?
do you prefer this image or the next one?
this is cropped a bit too tight at the top – the new leaves are almost cut-off in the frame.
Lycopodiums and Lichens
flash photo of a foliose lichen – the image is sharp and has good depth-of-field, but the dark background is somewhat “un-natural”……… 131/5000 Did you mean: flash photo of a foliose lichen – the image is sharp and has good depth-of-field, but the dark background is somewhat “unnatural”. Foto de flash de un liquen folioso: la imagen es nítida y tiene buena profundidad de campo, pero el fondo oscuro es algo “no natural”.
………esta imagen muestra el problema con la luz del día y las sombras, un poco de contraste entre las partes iluminadas de los líquenes y las partes sombreadas.
a “clean” lichen – without distractions and the lighting is uniform. But the subject seems “bland”……..un liquen “limpio” – sin distracciones y la iluminación es uniforme. Pero el tema parece poco interesante. – not very interesting.
another lichen – the contortions are interesting………otro liquen: las contorsiones son interesantes.
a fruiticose lichen, with hand for scale………….un liquen forma de fruta, con una mano para escala.
compare with the previos photo another lichen with a different hand……….compara con la foto anterior otro liquen con una mano diferente …
what is good or bad about this image? It shows two lichens, several mosses and dead lycopodium-type leaves………..¿Qué es bueno o malo acerca de esta imagen? Muestra dos líquenes, varios musgos y hojas muertas de tipo licopodio …
a Lycopodium species……….a Lycopodium species….
another Lycopodium – perhaps the same species as the previous image?……….otro Lycopodium – tal vez la misma especie que la imagen anterior?
What is this?? ¿Que es esto?
Another: What is this??……..Otro: ¿Qué es esto?
Examples of leaves eaten by insects
I tried to make sure the leaf was in focus but the background wasn’t. To do this required shooting perpindicular to the leaf surface…
this tree/shrub was heavily insect eaten, a closer view is in the next image.
individual leaf, almost devoured… this image is too dark, but unavoidable because of the bright background.
is this or the next image better to show a well-eaten leaf (or leaves)?
compare with the previous image
Artsy efforts (black/white for business cards??)
Very contrasty subjects – but ones having interesting outlines, can sometimes be useful subjects to photograph. The images below show some examples – these are not very good, but by enhancing the contrast and converting to grayscale or black and white in post processing permits the outline of the subject to be the focus of the photo.
a branch with epiphytes. Can you identify any of them?
another part of a tree with epiphytes
a crop of a heavily-laden tree with epiphytes
an entire tree with epiphytes
this isn’t black/white – it is grayscale, in the fog.
another tree with epiphytes
the standard tree fern type of photo
a closer view of the tree fern leaves, minus the trunk
another tree fern – is this better of worse than the previous image?
new leaves from the Tree Fern crown
bamboo – compare with the next 4 images
closer view of bamboo leaves
yet closer view
compare with the previous image – which is more “effective”
this beetle is mostly out-of-focus due to shallow depth of field – due to low light levels,,,but the colors are striking, and are probably sufficient to identify the species.
a relatively drab beetle, but with interesting dimples on its back.
sometimes you have little control – here the beetle was escaping and under vegetation. Possibly sufficient to identify the species – but not a prize-winner for sure!
this image shows a beetle engaged in its main activity of eating the leaf of a plant. The beetle’s shell isn’t entirely in-focus, the the leaf is, as is the mouthpart.
an insect on a composite flower. Ideally you want the head of the insect facing the camera and in focus, neight is present in this image. But the patterns on the wings might be sufficient to identify the species…
a fly on a composite.
a closer crop of the previous image – and some sharpening has been applied. This image shows the fly much better.
a butterfly. I have slightly brightened the thorax – it was darker on the original.
this butterfly isn’t entirely in-focus, and is facing away. It is the type of photo you take to document the fauna of a region – not to win prizes…
The butterflies are on the cow-pattie. Such an image can be used to discuss nutritional needs of butterflies…
a photo of the same subject as in previous image – but lower to the ground. I like this image better.
A caterpiller – hairy one that probably has poisonous spines. A flash photo, with a macro lense.
same caterpiller as in previous slide, only curled up. Often you must wait suitable poses of an organism (not necessary for plants!)
The images below are included more as test questions and to explain how they were taken (and why).
Is the subject the Rufous Collared Sparrow (Zonotrichia capensis) or the introduced Pinus patula? Native and non-native?
this fern frond isn’t perfectly sharp. Ideally you want camera pointing perpendicular to plane of the subject, to get maximum focus of the subject and minimum distracting background. Wasn’t entirely possible here.
another fern frond, not fully unraveled. Also, in the fog.
compare this photo of the fern frond with the next image – only real difference is more depth-of-field on the second image. Which is more effective?
version 2 more depth-of-field
Is this composition – or the next one better for the subject of the fern. For the subject of the Yungas forest floor?
the alternative to the previous image…which is better?
I isolated the subject here by getting low and shooting across so the background was distant – over the edge of the road and down the slope. Still, the subject isn’t entirely in-focus because I wanted to make sure the background was “defocused” and thus not distracting.
this photo was taken to show the reddish “fuz” (not a technical description!) on the leaf surface
Some final comparisons
Exam question: Which image in each set do you like more. Why?
Main leaf node below the center of the image……..Nodo de hoja principal debajo del centro de la imagen
leaf node roughly in center of the image……..nodo de hoja aproximadamente en el centro de la imagen
leaf node above the image center………nodo de hoja sobre el centro de la imagen.
These two photos of a epiphyte-laden tree were taken at different times during the walk. Which would you use in a document summarizing the walk? Which would you use to emphasize the landscape of the Yungas road? Why?
photo of tree with epiphytes with clear background……..foto del árbol con epífitas con fondo claro
same tree (slightly different composition) under foggy conditions………mismo árbol (composición ligeramente diferente) bajo condiciones de niebla
Cerro San Pedro and some of its cacti
After we returned from the visit to the Yungas, a small group decided to visit the Cerro San Pedro, above the city of Cochabamba. The motivation was to see the cacti on the hill and other dry flora not evident on the Yungas trip. I must say that Rosario and I perhaps initiated this visit, given our interests in cacti, but Andrea Soliz had also been interested in the cacti of Cochabamba. She had spent time on the Cerro with other students…
Two Google Earth views of Cerro San Pedro are below; one shows the entire Cerro and road, while the second shows where we hiked in the brief time we were on the hill.
The Cerro San Pedro surrounded by the city of Cochabamba. Click for a larger image.
The approximate area where we were walking on the Cerro. Parodia’s, Echinopsis and the arborescent cacti (Cereus, Harrisia and Cleistocactus) were found here, as well as essentially all other succulents we saw in our short time on the hill.
Our visit was necessarily short – both because of limited sunlight and because the road to the Cerro closes at a specific time and we had only about 30 minutes available to us. We stopped short of the actual Cerro with the Christ statue, and walked along a trail that others had clearly used for other purposes, as toilet paper was quite evident. Farther on, the trail was cleaner.
We found a reasonable diiversity of cacti and a few other succulents on the slopes of Cerro San Pedro, especially given the short time available for searching. Large Cereus hankeanus, Harrisia tetracantha and Cleistocactus parviflorus were numerous, and among the shrubs we many small Echinopsis. On rocks were small Parodias. An Opuntia sulfurea and a Tacinga-type Opuntia was also evident. There were introduced Agave and Opuntia ficus-indica as well. Among the Bromeliaceae were a Puya species and several Tillandsia – certainly more were present that we did not see.
A large Cereus hankeanus
A view of a Harrisia, with Cleistocactus in the background.
Another view of a Harrisia – here the plant is against the sky on a ridge top. This is one way to reduce distracting backgrounds, but it depends very much on the light.
Another view of a Harrisia with low sun angle. The background is a bit distracting, but out-of-focus at least.
A Harrisia with a natural background. Which one of these Harrassia photos do you like most? Least?
a view towards the south from the road up the Cerro
Cleistocactus parviflorus clump.
close-up of one Cleistocactus stem, with a flower. Unfortunately the flower (on left) is in the shade, but the background is also darkish – so the result is “tolerable”. The very low sun angle helped..
A cluster of Echinopsis cochabambensis stems.
A closer view of Echinopsis with flower buds. All of these plants were in a state of considerable dessication due to drought and being at the end of the dry season.
An Opuntia (Taacinga?) species
A Parodia schewbsiana (being shaded to reduce contrast). How large is the plant? Hard to judge without a scale.
Rosario’s finger and ring next to a small Parodia. Now we have scale. Unfortunately the finger is out-of-focus, but this is perhaps tolerable, though not ideal.
A Tillandsia attached to a shrub – compare with the next image.
same plant as in previous image but now I shaded the plant with my body to reduce contrast. Which image do you prefer? Neither is great…
A Puya glabrescens with flower stalk. The background was not ideal, but there was no time to find better specimens.
a closer view of the Puya flower – a bit too contrasty.
The Cristo… as close as we got to it.
A final example of how subtly modifying an original image can “help” the final product, see the two crops of the Cleistocactus stem and flower shown in the mosaic of images above. The first image showsthe original image (cropped) with the sunlight side of the stem somewhat too bright and the flower and dark side of the stem a bit too dark. By using a brightnening brush on the dark side and a darkening brush on the bright side the overall contrast across the stem has been diminished – though not excessively so. This might make the modified image easier to reproduce.
the original cropped image……….la imagen original recortada
the reduced contrast image……….la imagen de contraste reducido
Our day-long field trip to the Yungas was a success (from our perspective) and very enjoyable. I had not spent that much time in a cloud forest – perhaps ever. And the trip up Cerro San Pedro, though short, gave us a chance to see dry, cacti-covered hillsides that it turns out we could not see elsewhere during our 10-day stay in Bolivia. And the Congress, though relatively small compared with most others I had experienced in my research career, was great in providing many opportunities for personal discussions with the students and more senior personnel that participated.