Category Archives: Wildlife

The Raw and the Cooked – Choosing an Image File Format – Wildlife Photography Tips #4

This article was also published in The Blue Bill, the Quarterly Journal of the Kingston Field Naturalists, Volume 67, No 2, June 2020.

JPEG vs Raw
Rufous-capped Antthrush at ISO 8000

I started this article intending to talk about post- processing – the business of editing your wildlife images. But I rapidly realized that it is too big a subject to deal with at once, so I’m going to break it into manageable chunks.

How the Camera Creates an Image

The first stage of the journey requires us to look at what happens when you snap the shutter. In the days of film cameras it was relatively straightforward – light passed through the lens and onto a film of celluloid or plastic. Light-sensitive chemicals on the film reacted to the exposure, producing a negative or a slide.

Digital cameras use a different process to capture an image. As photographers we need to have a basic understanding of how this works so we can understand how the different image file formats work.

In very simple terms, in a digital camera the light is focused on a sensor, which is a grid made up of very small photosites. Each photosite contains a diode that converts light into digital information. In simplistic terms the diode counts the number of photons that fall onto it while the shutter is open, and the circuitry in the photosite coverts that information into a numerical value.

In order to provide a digital image that matches the level of detail and colour that the eye can see, a camera sensor needs to contain millions of these photosites. This density of information allows a digital image to be at least as good as an image from a film camera. But it also explains why digital image files tend to be very large. Each of those millions of photosites generates a numerical value expressed as a byte of between 12 and 24 bits. To give you an idea of how that adds up, with my current camera set to the highest resolution the information stored by those photosites totals 62 million bytes of data for a single image.

Image Formats

JPEG vs Raw

The camera’s onboard processors convert those digital values into an image file. There are two main formats for an image file – JPEG and Raw. These formats take very different approaches to the challenge of storing all this data. In simple terms, JPEG transforms data within the camera to produce a finished image, while Raw stores all the information and the user then processes the information at a workstation. Each approach has its the pros and cons. I want to briefly illustrate the difference so you can make an informed choice about which format to use.

JPEG

JPEG (Joint Photographic Experts Group) has emerged as the standard format for most photography tasks. For virtually all digital cameras JPEG is the default format, so if you have not been experimenting with the settings menu you are almost certainly shooting JPEG.

The JPEG format was developed to allow onboard compression of digital images. If you recall that figure of 62 million bytes you will see why for many applications there is a need to compress digital images.

Large files are problematic for several reasons:

  • They demand large storage capacity on your camera’s memory card
  • They take more time to write to the memory card, which can limit the number of images you can take in quick succession
  • They take up a lot of room on the storage drives of your PC, laptop, or mobile device
  • They require a lot of bandwidth to transmit, so websites will be slow to load and sharing is tedious

To avoid these problems the JPEG format compresses the raw information gathered by your camera sensor and then transforms it into a finished image. This image is stored on your camera’s memory card.

JPEG Advantages

For many uses JPEG format is ideal:

  • JPEG images are small enough to be easily viewable and shareable.*
  • Virtually all devices and software are compatible with JPEG files.
  • The simple image editing software available on your cell phone, tablet or computer is designed to use JPEG images.
  • JPEG is supported by HTML, the language used in creating web pages.

*Note: JPEG files can be created using different compression levels. Lower compression levels lead to better quality but also larger file size. JPEG Fine files are the least compressed (4:1) but therefore the largest. At about 10MB each in the Large size they are not easily shareable.

JPEG Disadvantages

However, there are limitations to JPEG that you should consider. Most of these limitations result from the way the JPEG algorithm compresses the image file size.

The process by which JPEG compresses a file is highly technical bordering on incomprehensible, but in the simplest possible terms it reduces the size of the file by calculating average values for 8×8 blocks of photosites (thus each block replaces 64 sets of information with one). It then reduces the level of information about colour. Based on the understanding that humans have difficulty discerning small variations of colour, JPEG looks for areas that have similar hues and replaces these small variations with a single average colour.

This process can result in a much smaller image file, but the key thing to remember about the JPEG conversion process is that once the image is created any information that the conversion algorithm considered unnecessary is lost and unrecoverable.

This is why JPEG is classified as a “lossy” format. As noted, a certain amount of information is discarded when the image is originally created. Moreover, each time you recompress the image, by making a change and then re-saving it, some additional information is irrecoverably lost. And if you crop an image – for example to provide a close-up view – the parts of the image that you cropped out are lost forever.

A further implication of JPEG is that, because it produces a final image, the camera settings in use when the image was taken are “baked in”. If you realize afterwards that you had the wrong white balance or picture control settings for example it may not be possible to correct the image.

Raw

Raw is a generic term for a file that saves all of the information from an image, with only minimal processing. This information needs to be converted and edited at a workstation before an image is produced.

Raw format is not available on all cameras. All modern digital single lens reflex cameras (DSLRs) and mirrorless cameras can shoot Raw, but only a minority of bridge cameras have the capability and point-and-shoot cameras generally do not.

Raw Disadvantages

There are several disadvantages to shooting in Raw:

  • Raw files are big. With the camera set-up I currently use, each image file is about 29MB. So a 64GB card will hold about 1,300 Raw files instead of 13,000 JPEGs.
  • You need to process your Raw files at home in order to generate finished images. This is time-consuming compared to the instant image generated by JPEG.
  • To process the files you need specialized image editing software (though note that you can download free editing software from your camera manufacturer – all the major camera brands provide this).
  • Each camera manufacturer has its own a proprietary standard, so a for example a CRW file from a Canon camera is not compatible with a NEF file a Nikon generates.
  • For Raw files to be printed, shared on a mobile device or posted on the internet you need to create and export a JPEG image.

So why do most professional wildlife photographers shoot in Raw?

Raw Advantages

Lossless. Raw files are lossless. All the information your camera gathered is available to you. Nothing is averaged out or approximated. As an example, an 8-bit JPEG image is limited to about 16.8 million colours, whereas a 12-bit Raw image can show up to 68.7 billion. What this means in the real world is that you will get more even transition between colours, without the possibility of the pixilation that sometime happens with JPEG (remember that JPEG averages out colours into larger blocks).

Non-destructive. The adjustments you make in post-processing do not change the original file. All changes are saved in a separate hidden file called a sidecar. So regardless of how much you crop and adjust an image, you always have the original file available. With JPEG every significant change degrades the image, and things that are cropped out cannot be recovered.

Settings are not baked in. With Raw you have complete ability to adjust most of the camera settings during post-processing, including exposure, white balance, sharpening, colour gamut, picture control, and contrast.

Greater dynamic range. Raw files are typically created in 12 or 14-bit format, compared to 8-bit for JPEG. This may not seem like a big numerical difference, but remember we are looking at a file made up of millions of bytes. The math is somewhat beyond my ken, but the impact is that in each stop of a camera’s dynamic range there is far more information space available in a Raw file. At the bottom end of the dynamic range – areas of deep shadow in a photograph – there are 65 times as many gradations in a Raw file as in a JPEG.

This has important implications for wildlife photographers. We often find ourselves trying to capture images in areas where there is both bright light and deep shadow. Using JPEG, those shadows will tend to be featureless dark blobs, whereas with Raw we will be able to see the same details that our eyes would see.

Moreover, the greater ability of Raw to capture detail in shadow allows us to apply shadow reduction – a very useful capability that I will talk about in future articles on post-processing.

Exposure Correction

But perhaps the most striking advantage comes when we shoot images at incorrect exposures. The perfect photographer would never do this, but for the rest of us there will be numerous situations were we have the camera set up for bright daylight only to have a momentary glimpse of a bird – and typically it’s a good one – peeping out of a dark corner.

The higher dynamic range of the Raw format means we can correct a badly underexposed shot in post-processing and end up with a good image.

Consider this example. I deliberately underexposed this shot of an American Goldfinch in my garden.  I did this as an experiment, so please ignore the uninteresting composition. The camera took two simultaneous images – one in Raw and one in JPEG Fine.

Original image

The images were very dark – I had to increase exposure by about four stops. But the results are clear. The quality of the Raw image is pretty good: there is full feather detail and the colours look right . The JPEG image on the other hand is dreadful. The colour is over-saturated, green blobs have appeared in the breast and belly plumage, and the whole bird looks flat and dull.

Recommendations

If you have read this far, you have probably realized that I am a fan of the Raw format. I believe that in wildlife photography the aim is should be to produce an image that replicates as closely as possible how the creature (bird/animal/plant/butterfly/reptile) looked in the wild. I have found that using Raw format and carefully post-processing the image gives me the best chance of doing that. And there is an element of craftsmanship involved that I find appealing – I prefer to make my own choices rather than having the camera make decisions on my behalf. I am also not worried about file size given that hard drive storage capacity has become increasingly inexpensive.

So is there an argument for using JPEG? The fact remains that some very good images have been created using JPEG. You may well decide that you prefer the simplicity and efficiency of JPEG. If so, I would recommend that you use the lowest compression setting: JPEG Fine. This setting creates a 4:1 compression, so the files are still fairly large, but at 4:1 you will not see any of the artifacts or errors that can creep in at higher compression ratios.

Other topics in this series

Wildlife Photography Tips #1 – Exposure Compensation

Wildlife Photography Tips #2 – Shutter Speed

Wildlife Photography Tips #3 – Back-Button Focus

Birding Colombia’s Llanos – Hato la Aurora

Llanos Birding

Birding Colombia's Llanos

When we last saw our heroes, they were being bird-bedazzled during the long march into the grassland plains of the Llanos…

After a long, hot and bird-filled journey we rolled into the lodge in the late afternoon. Our options were: (a) have a well-deserved siesta, relax and await dinner, or (b) bird the local area. A difficult dilemma, one might imagine.  So by dinnertime Pale-headed Jacamar, Southern Beardless Tyrannulet and Pale-eyed Pygmy-Tyrant among others had found their way onto the trip list.

Red Howler Monkey
Birding Colombia's Llanos
Pale-eyed Pygmy-Tyrant
Capybara on the move.
Continue reading Birding Colombia’s Llanos – Hato la Aurora

Exposure compensation: Don’t Blow Up Your Gulls

WILDLIFE PHOTOGRAPHY TIPS #1

Originally published in The Blue Bill – the quarterly journal of the Kingston Field Naturalists

I am not an expert photographer and this post is not intended for experts. I became interested in wildlife photography when I was planning a trip to Tanzania in 2015. It was likely to be a once-in-a-lifetime trip and I wanted to come back with some good wildlife photos. So I obtained a decent camera and lens and took a short photography course before we left. The results were encouraging, and I could see that with more knowledge and experience I ought to be able to capture even better images.

In a way photography is like birding: the is an infinite amount of information, so there is always something new to learn. And like birding, photography rewards both study and practice. Through trial and error I have learned a fair amount about the craft of photography over the last few years. This post is intended to share things I have learned on my journey that may be of use to other aspiring photographers.

Understanding Exposure Compensation

In this first installment I want to talk about exposure compensation. It’s a camera function that many amateur nature photographers I have met seem unaware of, but in certain situations it is a really important tool to ensure you get the image you want.

I won’t get into a long explanation of how camera light metering systems work. Suffice it to say that most of the time they work very well. But there are a few situations in wildlife photography where left to its own devices the camera will make the wrong decision. Knowledge of how to compensate for this will help you get the right exposure and avoid disappointment. Those situations are:

  • Backlighting
  • Shadow
  • Wetness and Whiteness

Backlighting

Let’s start with a common situation: birds up in the treetops, or in the case, a bird on a wire. You see a Mourning Dove; your camera sees a mostly light background with one dark object. So it averages out the exposure and you are left with something like the image in photo 1 – a dark blob. After I took the first image I adjusted the exposure compensation two steps to the left (to -0.7) and photo 2 was the result. The bird is correctly exposed and all its plumage details are visible (e.g. the thin blue eye ring).

Of course I could have adjusted the exposure of photo 1 in post-processing, but the best-looking images start with a file that is correctly exposed in the first place. This is particularly important if, like most photographers, you shoot in a lossy format such as JPEG. Each time you edit a JPEG file more data is lost, so the closer you get to correct exposure in the first place, the better your final image will look.[1]

Shadow

Metering systems also struggle to correctly expose objects in shadow. Photo 3 shows a pair of Hadada Ibis from that trip to Tanzania. The birds are underexposed because they are in shadow and there is bright sunlight on the right side of the image. The metering system tried to average out the exposure, which left the birds in the dark. In this case positive exposure compensation – moving the exposure one or two steps to the right – would have produced a better image (photo 4).

Wetness and Whiteness

Bright spots also cause trouble for the metering system. In wildlife photography this often shows up when photographing in bright sunlight. Anything white or wet can end up being overexposed even if the rest of the exposure is good. So gulls, terns and white pelicans are a problem, and so too are turtles and frogs when the sun is shining on their shells or skin.

In the case of bright spots, the issue is that the image may look properly exposed, but on closer examination the highlights are blown out. Blowing out, also known as clipping, happens where the intensity of light in a certain area exceeds the camera’s ability to capture information. So a blown highlight may look white, but if you look closely you will see that there is no detail in that part of the image.

Consider photo 5 – a Ring-billed Gull in sunlight. The image looks properly exposed, but if you zoom in (photo 6) you will see that there is no feather detail – it’s just a blank field of white. Sadly, blown highlights are on thing that cannot be corrected in post-processing, as there is no data to work with.

Here again, exposure compensation comes to the rescue. In photo 7 I deliberately underexposed the image by adjusting exposure compensation two steps to the left (-0.7). In post-processing I was able to increase the exposure so the gull is properly exposed, but as a blow-up shows (photo 8) the plumage details in the white area are fully visible.

Using Exposure Compensation

If you want to experiment with exposure compensation, the first step is to find how to adjust exposures on your camera. I recommend reading the relevant section of the manual, which will show you where the adjustments are made. On most DSLR camera bodies you will find a button that looks like photo 9. On bridge cameras, it is more likely to be a multi-function button. Typically you will need to hold down this button while moving one of the rotating dials or switches to adjust exposure up or down. In either case you will be able to see your adjustments on the exposure compensation slider, which is usually visible in your camera viewfinder.

Photo 9

Three Important Tips

1. The monitor (LCD viewscreen) on the back of your camera allows you to test and adjust. So when you come across your quarry and the lighting may be problematic (backlit, shadow, wet or white) take a photo to start off, then if the bird or beast stays around, look at your monitor to see if the exposure is good. If not, try an adjustment of two steps, reshoot, and check the monitor. Continue testing and adjusting until you either get the perfect exposure, or more likely, the bird of beast absconds.

2. Most cameras have a function that will show blown highlights in the monitor. For Nikon cameras it is cunningly named Highlight Display. Again, check your camera manual to see how to activate this function. When activated, if you take an image and look at the monitor you will see flashing lights (photographers call these “blinkies”) in areas where there are blown highlights. This quick check will let you know whether you need to adjust the exposure. Note that for backlit objects, if the object itself is correctly exposed there will probably be blown highlights in the sky behind it. This is not really a problem other than the fact that the sky tends to end up white rather than blue.

3. In most cases your camera will not automatically default back to the zero position once you have taken an image. I won’t tell you how many times I have forgotten to take account of this and taken a quick snap of a rapidly-departing bird only to find that exposure compensation was set for shadows and the image was mostly blown out. It seems that the rarer the bird, the more likely it is that this happens!  So you will want to keep exposure compensation in mind as part of your mental checklist.

Happy photography!


[1] Wikipedia has a good article on JPEG. See the section entitled Typical Usage at https://en.wikipedia.org/wiki/JPEG

Costa Rica

Why Costa Rica?

Well, that’s not really a question people ask. More like “when are you going to Costa Rica?” We went for a look around in March, just the latest in a long line of tourists lured in by Costa Rica’s rare combination of a warm climate, huge amounts of biodiversity, friendly people and – almost unique in Central America – stable, democratic government. No wonder they are the Happiest People on Earth![1]

It’s a popular destination for beach vacations, adventure travel and surfing, but the variety and density of wildlife makes it a very compelling destination for nature trips. For the record: Costa Rica accounts for 0.03 percent of the earth’s surface (51,100km2), but contains nearly 6 percent of the world’s biodiversity.[2],[3] Costa Rica was also an early adopter of the notion of eco-tourism, and has made major efforts to ensure that all that biodiversity is protected and made accessible to nature-lovers, both foreign and domestic.

White-faced Capuchin - Costa Rica
White-faced Capuchin

Background

During the 1960s the growing demand for agricultural land, mainly cattle pasture, was leading to widespread deforestation.  The resulting pastureland was not particularly productive, and the usual results of deforestation – flooding, erosion, loss of wildlife – were becoming increasingly evident. Unlike many developing countries, it seems that Costa Ricans, or Ticos as they call themselves, were unwilling to sacrifice their natural resources for short-term economic gain. Starting in the 1980s, programmes were established to protect large areas of the different ecosystems. The National Parks and Reserves now cover 12 % of Costa Rica’s land area, with another 16% protected by various refuges, indigenous Indian reserves, and nature reserves. So Costa Rica stands proudly with Colombia and Tanzania in the select group of countries that have preserved significant parts of their natural environment against the depredations of developers.

Key Sites

I’m not going to bore you with a minute-by-minute account, instead focus on a few sites that were highlights of the trip.

Butterfly Ranch

On Day One, enroute from San Jose to Arenal, one of our stops was the Pierella Ecological Garden – a butterfly ranch. Twenty years ago the proprietor of the garden was seized with the notion that he could make a business out of selling butterflies in chrysalis stage to zoos and butterfly sanctuaries (such as the Butterfly Conservatory in Cambridge, Ontario). He acquired some marginal pastureland and began planting the native trees and shrubs favoured by different butterfly species.

William, the butterfly rancher - Costa Rica
William, the butterfly rancher

Of course as the garden grew into a forest lots of other wildlife recolonized it, so in addition to seeing the whole process of raising butterflies we had great opportunities to see birds, poison dart frogs, exotic insects, a caiman, and a sloth. We were completely entranced by a clutch of Honduran White Bats – tiny creatures that make a tent to roost in by clipping a seam in a heliconia leaf so it forms an inverted V. After our nature walk we had an excellent lunch while enjoying close-up views of birds gorging themselves on fruit at the nearby feeders. The proprietress also demonstrated the laborious process by which cocoa beans are turned into chocolate – with appropriate samples at each stage.

Honduran White Bats in their tent. Costa Rica
Honduran White Bats in their tent. (Dodgy cell phone photo)

Arenal

Sunset on the deck - Arenal Observatory Lodge. Costa Rica
Sunset on the deck – Arenal Observatory Lodge

Our first two nights were at the Arenal Observatory Lodge and Spa, which sits at the foot of an active volcano. Fortunately it has not had a major eruption since 1998, and it continued to behave during our visit. The lodge is extremely comfortable, and well equipped with a swimming pool, a large whirlpool bath/hot tub, and a good restaurant. The large viewing platform next to the restaurant provided an excellent observation point where we could watch masses of birds in the trees and on the feeders and coatimundis patrolling below, all whilst sipping a refreshing Guaro Sour.

Arenal, venting a little steam. Costa Rica
Arenal, venting a little steam.

We spent two days exploring the network of nature trails that emanate out from the lodge and provide access to the rain forest. We also took a night walk to investigate the frog pond and were rewarded with good views of the iconic red-eyed tree frog.

Red-eyed Tree Frog, Costa Rica
Red-eyed Tree Frog and friend.

The highlight of our time in Arenal was seeing a Margay (aka Tree Ocelot)– a rare and secretive jungle cat not much larger than a house cat. I had wanted to see one since I saw a photo when I was about 12, but never really expected to realize that dream. ¡Me quedé con la boca abierta! Fabulous.

Margay - Costa Rica
Margay, trying not to be seen.

Mangrove Boat Tour

On the southern end of Costa Rica’s Pacific coast lies the Osa Peninsula, a thinly-populated area mostly comprised of mangrove swamps. We took a small boat out of Sierte for a cruise of about two hours.[4] Our skipper, Eagle-Eye José, was adept both at spotting wildlife and at manoeuvring the boat for close-in views. In addition to some highly sought-after birds, we also saw all three species of Costa Rican monkeys along with a selection of bats, lizards, a river turtle and the only snake of the trip. José’s ability to bring the boat in close meant that everyone was able to see all the wildlife without having to struggle with binoculars, and to take good photos even if they didn’t have a long telephoto lens. Being “all in the same boat” we moved at the same pace, and could all see the wildlife at the same time. It was hot and steamy on the river but the boat had a canopy and cold drinks were available so it made for a very pleasant excursion.

Central American Squirrel Monkey, Costa Rica
Central American Squirrel Monkey, chilling.

Eagle-Eye José, Costa Rica
Eagle-Eye José

Scarlet Macaw, Costa Rica
Scarlet Macaw

Bosque del Tolomuco

Bosque del Tolomuco, Costa Rica
Bosque del Tolomuco

Up in the cloud forest near San Isidro is a scenic nature reserve and lodge owned by two ex-pat Canadians. Over the years they have planted a wide variety of native plants that are favoured by butterflies and hummingbirds, and the results have been spectacular. We stopped at Bosque del Tolomuco for about an hour and had close views of 14 species of hummingbird including the scarce White-crested Coquette and the stunning Violet Sabrewing. Silver-throated and Flame-coloured Tanagers and pair of Red-headed Barbet were features among the non-humming birds. Parrots and parakeets are apparently regular visitors as well. Sadly we were only passing through, but I have a strong desire to go back, rent one of their peaceful cottages and just hang out for a week or so.

Violet Sabrewing, Costa Rica
Violet Sabrewing

The Trip

Our trip was organized by Worldwide Quest, a Toronto-based firm that specializes in trips that combine excellent wildlife experiences with relatively luxurious accommodation. We had been to Tanzania on a Worldwide Quest tour so we knew that we could expect to be coddled … and we were not disappointed. However there are numerous other travel companies that can offer the same level of wildlife viewing and perfectly acceptable accommodation at a lower price. And it would be entirely possible to rent a car and do a self-guided trip. Once outside of San Jose the traffic is reasonable and most of the roads are in good condition. It is also possible to hire a vehicle and driver, and firms such as Tico Rides will help you plan your itinerary to make best use of your available time.

The List

“It’s all about the list” – The Birdfinder General

My species list for the tour includes:

Birds: 262 species. Click here for a photo gallery.

Mammals:

– Monkeys: White-faced Capuchin, Mantled Howler Monkey, Central American Squirrel Monkey

– Sloths: Brown-throated Three-toed and Hoffman’s Two-toed

– Central American Agouti

– Variegated Squirrel

– White-nosed Coati

– Alston’s Mouse Possum

– Margay

– Bats: Long-nosed, Honduran White

Frogs: 7 species

Lizards: 7 species

Snakes: Rainbow Boa

Turtles: Black River Turtle

Crocodilians: Spectacled Caiman, American Crocodile

Butterflies: 21 species

So… only about 600 bird species to go!Costa Rica

[1] The happiest country in the world according the Happy Planet Index, though merely the 13th happiest according to the UN’s World Happiness Report.

[2] Biodiversity can be defined as the totality of genes, species and ecosystems of a region. – Young, Anthony. “Global Environmental Outlook 3 (GEO-3): Past, Present and Future Perspectives.” The Geographical Journal, vol. 169, 2003, p. 120, from https://en.wikipedia.org/wiki/Biodiversity

[3] For comparison purposes, New Brunswick is 72,908 km2.

[4] Not the dreaded three-hour cruise.

New additions

OK, so I haven’t been posting much lately for a variety of reasons. This is just to advise my vast readership 😉 that I have put up a number of new pages, grouped under the Creatures tab. They include photo galleries of Arizona Wildlife, Birds of Cuba and Butterflies. I’m pestering you with this post because when I create a new page the system does not advise subscribers like it does when I post something. And of course you have been waiting with bated breath for more animal photos to brighten up your day!

Such as this one…

Lion Attack!

Warning: this post contains some red-in-tooth-and-claw images.

Wildbeest drinking, Serengeti NP
Wildbeest drinking

I have been (finally) going through our pictures from the Tanzania trip and I though you loyal readers might find these ones interesting. We were fortunate enough to see a lion attack play out right in front of us, thanks to some expert positioning of the vehicle by our driver/guide Fredrick Kissenga.

Continue reading Lion Attack!