March 29, 2013

How to measure the distance to an object in a photo?

How to measure the distance to an object in a photo?

I recently took this video of a White-bellied parrot eating brazil nuts on top of a tree.  Its very difficult to see this sort of thing since the brazil nuts they are eating are so high up in the tree. 

To get the shot I climbed to the top of the 33m tower at Posada Amazonas then used a Canon 600mm f/4 with a 2x teleconverter and a Canon 7D for a total of 1920mm to take the video. Even though the camera was on a tripod I used image stabilization to remove any vibration that was induced by people moving on the tower. I then moved the video into iMovie and stabilized it even more just to be sure that all the shake was out:

A friend of mine asked me "How far away were you?"  I really didn't know so I set off to find out.

I have some experience with macro photography or photomicrography as it is sometimes called.  I use a high power lens to magnify subjects up to 7.5x.  At this magnification one can see all sorts of cool things..butterfly wing scales, compound eye structure of ants etc.

To find the size on a photo taken with a microscope you use the following technique:
  1. Take a photo of the object.
  2. Without adjusting magnification take a picture of a ruler
  3. Import both photos to photoshop
  4. Superimpose the photo of the ruler over the photo of the object using a opacity of around 50%
  5. You can now measure the length of the object.

I decided to use a similar technique for the bird.  Here is what I did.

I started with what was known:

  • Focal length 1200mm (1920mm with the 1.6 crop factor of the Canon 7D)
  • The average size of a White-bellied parrot is 23cm

I then made a scale on a whiteboard that was divided into 10 cm increments.

Using the exact camera setup that I used to take the parrot photo, I placed the scale along the street at known distances and took photos:

Scale at ~145ft

Scale at ~405ft

I then superimposed the scale over the photo of the parrot:

When the height of the parrot (23cm) was equal to 23cm of the scale I would check the distance that I took the scale photo at and then know the distance to the macaw.

It turned out to be that the photo was taken at a distance of around 150 meters.

Thats basically how its done. Hope that you liked the blog entry.

To learn more cool stuff about photography you can take a photo tour with me:



March 27, 2013

What Animal Can 'Say' 14 Different Words?

A juvenile makes 14 distinct sounds, each with a different meaning, just shy of the 22 noises used by gorillas.  Think of it like 14 different words used to communicate with a nearby adult. The adult males and females themselves live with the juveniles to feed them, protect them, and help them grow. They’re considered semi-social organism, living in small family groups. Sounds like a fairly advanced animal, right?

So what is it- A bird? A rodent? A dog? Here’s a hint- it lives in rotting wood, and has six legs.

Yes, it is an insect. Odontotaenius disjunctus, commonly known as a bess beetle (or crying beetle), and it has the most advanced sound-based communication system known in arthropods. You can find it under a moist rotting log anywhere from here in the Amazon up to New York. This beetle is large (~2 inches) and widespread and would be quite noticeable if it weren’t for its rather hidden natural history.

A bess beetle family, under a log.
Flip enough rotting logs, dig through enough decaying leaves, and you’ll eventually find a group of bess beetles get a look inside their fascinating life.. You’ll see a few adults, many grub-like larvae, and some round clumps of dirt that contain developing pupae. Poke around a bit, and the sounds begin. The beetle is known locally as a ‘crying beetle’ due to its ability to make a high-pitched whiny alarm call if you disturb it (like by picking it up). But the alarm noise from the adults isn’t the interesting one; what’s fascinating are the fourteen almost inaudible squeaks that the larvae make below.

All insects have six legs, including their larvae. But take a close look at these beetle larvae, you’ll see only two pairs of legs, for a total of four- so what happened to the other two? Over the course of evolution and thousands and thousands of years, the back pair of legs got smaller. Much smaller. They’re no longer used for moving around in dirt; rather they’re used to meaningfully strum a structure called a plectrum.

Bess beetle larva. Note only 2 pairs of legs.
Photo by Whitney Cranshaw, Colorado State University, Bugwood.org.

Imagine a tiny stump of a leg strumming a comb in various directions- that’s what is happening between the hind leg and the plectrum. As the stump hits the teeth of the comb at different angles or different timespans, the frequency of the sound changes ever so slightly, resulting in overall different noise, or call. Researchers listening in found that there were 14 distinct noises made in a variety of situations via this stump-and-plectrum combo.

What we don’t yet have is a translator. Does one larva squeak mean “feed me!” (which adults do by defecating mostly-broken down wood)? Another angle strummed,  “Protect me! Someone lifted the log” or “Help me molt”?

Who knows. What we do know is this is a remarkably advanced sound-based communication system for an insect. Other insects stand out by their use of things like body movements or scented pheromones (ants and bees) to deliver complex bits of information, so it’s no surprise that an insect has evolved the ability to do that by making a noise, especially when living in a medium like soil in which movement is hardly visible and pheromones slow to disperse.

Some day, some scientists will figure out what these larvae are saying. And how fascinating that will be. Until then, flip a log, take a peak at this miniature advanced world, appreciate the wonders of nature, and don’t forget to (gently) put the log back in place.
March 19, 2013

How to use a telephoto lens to film macaws.

Jeff Cremer our in-house photographer and photo tour guide, is a master of using a high-zoom telephoto lens to capture some incredible wildlife. Watch below as he explains the secrets to using this camera, which you too can shoot with if you join us on a photo tour.

Make sure to watch for the incredible macaw footage at the end!

March 09, 2013

Steve Gettle Tambopata Photography Trip Report


I (Steve Gettle) just returned from a great trip to Peru where I visited the Tambopata National Reserve, a reserve the size of Belgum with 600 species of birds, 1300 different butterflies and 300 species of mammals. Not only was this trip productive photographically but it was also an epic adventure. After the flight into Lima it was just a short flight to Puerto Muldonado where I boarded a bus for the ride to the Tambopata River, where the real journey begins.

Once on the river I traveled by motorized canoe deep into the amazon jungle.  The destination is a series of three lodges which are located along the river, these lodges served as my base while I explored the area.  The last lodge deep in the jungle is actually a research center and arguably the most remote lodge in all of South America!

The main attraction here are the macaws. The Tambopta contains 10% of the world’s macaw population. And the world’s largest clay lick. Macaws gather at clay licks to ingest the clay where they get minerals that are not available in their jungle diet. While I was there I was able to not only photograph them at the clay lick but also to photograph them as they flew back and forth. Since they usually fly together as mated pairs, this is exponentially harder than shooting a single bird in flight.  Now not only do I have the shadows from the other bird to deal with, but I also have two sets of wing positions to worry about getting right.

In addition to the macaws there were tons of other birds as well as lots of amazing insects and amphibians that I shot on our nightly jungle walks.  You can see a gallery showcasing some more of my favorite images from the trip here.

I will be leading a photo tour to the Peruvian Amazon in the fall of 2013. In addition to duplicating this amazing adventure there will be an optional 4 day extension to Machu Picchu as well. More information will be coming in an upcoming newsletter.

A special note of thanks to Jeff Cremer of Rainforest Expeditions who served as my host and guide on this trip. we had a great time and an epic adventure.
March 06, 2013

A Turtle Drowning In Butterfly Kisses

This is a colorful example of how odd behaviors can evolve in the face of a limiting resource. In the Amazon, salt is a much sought-after commodity as it is generally lacking in the environment.

Turtle tears? A prime source of salt, and many butterfly species have adapted by perching on their face and sipping from the source. Although this is generally a common sight along the river, this image taken by our photo tour guide Jeff Cremer is the most adorably smothered I have seen, yet.

The turtles are basking in the sun to collect heat and energy for the day, and the butterflies find them by flying along the river. The turtles are ectothermic, so require heat energy from the environment to warm up their bodies and get active for the day. Bees also feed on turtle eyes, which seem to really bother the turtles, but they don’t appear to mind having butterflies drink from them as much.

We also have the first ever video taken of bees feeding on the turtles, here:

While some people have said that the turtle gets an eye cleaning in exchange, I’m don’t think that is very likely. More likely is that this relationship is a form of commensalism, in which the butterfly benefits from the turtle, and the turtle isn’t really affected either way.

Butterflies in this area will do anything for salt- including drinking from your sweaty skin or backpack. I’d even bet that if you laid out on one of those logs with your skin covered and your eyes open, you may get lucky enough and eventually have a swarm of colorful butterflies imbibing on your tears, too.

If you want to join us and experience the incredible sights of the Amazon, check out our tours.

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March 02, 2013

Top 5 Strangest Rainforest Animals

From a decoy building spider that would put Charlotte to shame to the caterpillar that has the same barber as Donald Trump, these are only a few of the interesting things that you can see in Tambopata.  

1. Decoy-building Spider - Check out the full article with video here

This decoy building spider shows 3D printers what’s up: It's a small spider that constructs a bigger, scarier spider in its web completely out of debris and dead insect parts. These images show the spider 'decoy' that the small spider, seen at the top of the decoy, created. Why does it do it? Researchers are still trying to figure it out, but it likely has to do with confusing predators and increasing its chances of survival. This spider was recently discovered and is the only animal ever recorded to construct a larger version itself. Where's the one place in the world to see this spider? A three-minute walk from the Tambopata Research Center.

2. Triple Rainbow - Full article with video here

A double rainbow once made a grown man cry, but this triple rainbow was so cool it would make Chuck Norris cry: Imagine looking off in the distance and seeing an upside-down rainbow above the trees. A recent sighting of this rare optical event in the sky resulted in the best photos ever taken of this unbelievable, rainbow-filled display as seen here. These solar halos result from interactions of the sunlight with ice crystals high up in the atmosphere, and according to experts Tambopata just happens to offer the right conditions to make this the most impressive sighting of these halos ever recorded.  This was seen along the Tambopata River on a photo tour.

3. Donald Trump's Wig

This animal is one of the most bizarre things you can come across in nature- Is it a fruit? A bird? A mammal? No- it's a caterpillar of a megalopygid moth. But don't be fooled by the nice, yellow fuzzy appearance, the hairs on this are full of urticating spines that can inject a very painful poison if touched. This caterpillar was spotted at the Posada Amazonas Lodge.

4. Basket Cocoon.

Humans have such lame growth into adulthood: The incredible woven lattice structure of the urodid moth's cocoon is an astounding example of art in nature. The cocoon dangles from a silken string about a foot long, likely to prevent ants from feeding on it, and the bright orange color can serve as a warning to potential predators that this cocoon may be poisonous to eat. The adult moth eventually emerges from the pupa, resting inside, and exits through the small tubular 'escape hatch' at the bottom of the structure. This pupa was seen at Refugio Amazonas Lodge.  

5. Macaw Clay Lick

A five minute boat ride from the Tambopata Research Center takes you to an island that overlooks one of the most incredible and colorful animal gatherings in the world. A wall of clay, over 200 feet across, where hundreds of individuals making up nine species of bright parrots, parakeets, and macaws gather every morning to feed on the sodium-rich clay.  This was also featured in a video by Destin of Smarter Every Day where he and Rainforest Expeditons photographer Jeff Cremer filmed the macaws with a high speed camera.

Extra: 16,000 Megapixel Image of Machu Picchu

If a picture is worth a thousand words how many words is a 16000-megapixel picture of Machu Picchu worth? This may appear to be a normal image of the Incan ruins of Machu Picchu. But try zooming in and you'll realize that this image is a whopping 16 gigapixels (16,000 megapixels), and the highest resolution image ever taken of the ruins. Using gigapan technology, Rainforest Expeditions photographer Jeff Cremer has brought access to this World Heritage Site to the masses like never before. If you're in Peru and on your way to Tambopata, be sure to stop by Cusco to see it in-person.

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