Photographing Yellow Robins

Recently I have made some posts on niche photographic topics. While these are interesting, they aren't actually supposed to be the main focus of my website. Most of my photos are of wildlife and birds in particular, but I haven't written anything about either. Without engaging in apologetics too much the reason for this is because it is winter. Winter is bad for wildlife photography for a few reasons. Firstly, it is really hard to get out and photograph. Being cold is usually easy to deal with. The wind on the other hand can make outdoor activity a real chore. The days are short which limits the amount of available to time go out and photograph. This is an acute issue because the free time I normally go shooting, the morning and evenings, are severely curtailed. Secondly, the lighting in winter is generally very poor. It is often cloudy which lowers the available light. Bird photography requires fast shutter speeds so poor lighting forces you to use uncomfortably high ISO levels. Further the quality of the light is poor as the clouds soften it and thus degrades the quality of the pictures taken. Thirdly, birds are more difficult to find. As part of the seasonal cycle many birds die off over the winter before being repopulated in the spring/summer. Obviously this means there are less birds around. Some birds migrate away so there is simply no chance of seeing them. A few token birds like the Eurasian Coot migrate here in the winter, however they are intensely uninteresting.

With all that being true, it isn't impossible to get some good birds shots in winter. I tried a few times and failed miserably. This time I set out for Sherwood Forest, which yielded better results. I have been to Sherwood plenty of times and it was featured in an earlier article Infrared Photography - The Cure For Haze as the vantage point from where I took my photos. Sherwood forest in a fascinating place. It marks the change in geography of the region from open grassland to the foothills of the Australian Alps. The actual 'forest' is part of a pine forest plantation which has its own unique ecosystem. There are wild pigs which live in the forest although I don't have any pictures. Getting some would be somewhat dangerous. I found a dying Bassian Thrush there in the summer which was truly fascinating. All that is to say there is a lot to see there if you go looking for it.

Dying Bassian Thrush (7D Mk. 2 + Sigma 150-600 f/5-6.3 + Extension Tubes: f/7.1 ISO-500 1/250 sec. @600mm)

Dying Bassian Thrush (7D Mk. 2 + Sigma 150-600 f/5-6.3 + Extension Tubes: f/7.1 ISO-500 1/250 sec. @600mm)

I went back there this time to shoot Yellow Robins. I had noticed the last time I was there for the infrared haze article, a large number of both Yellow and Scarlet Robins jumping around on the Verbascum (a type of tall weed birds can perch on). That wasn't surprising to me. Most small birds move out of the mountains and bush towards the city in the winter searching for food. Robins don't. I am not sure why. Yellow Robins in particular aren't averse to human contact. I think it might have something to do with a preference for cooler climates as they are fairly common even at the top of mountains. I've had Scarlet Robins appear at the top of Camel's Hump before. Given this knowledge my plan was to take a chair up the hill at Sherwood Forest where all the Verbascum is and wait. So that is what I did.

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/7.1 ISO-160 1/500 sec. @600mm

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/7.1 ISO-160 1/500 sec. @600mm

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/7.1 ISO-250 1/500 sec. @600mm

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/7.1 ISO-250 1/500 sec. @600mm

Almost immediately the Yellow Robins came around. They hunt in groups and move from stalk to stalk looking for bugs to eat. Initially they kept there distance from me. Still, with a good 600mm lens I could get nice shots of them regardless. It helped that it was a nice sunny day and I had positioned myself with the sun to my back so the birds would be perfectly illuminated.

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/8 ISO-160 1/500 sec. @600mm

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/8 ISO-160 1/500 sec. @600mm

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/8 ISO-320 1/500 sec. @600mm

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/8 ISO-320 1/500 sec. @600mm

Waiting around was nice and easy with a chair to sit on. I had brought my monopod with me to rest my lens on making the task even easier. As I kept still and quiet the birds got used to my presence and slowly crept closer. Some Scarlet Robins did pop up now and then, but they are generally more timid than Yellow Robins and decided to keep there distance from me.

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/8 ISO-400 1/500 sec. @600mm

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/8 ISO-400 1/500 sec. @600mm

I got a few shots but given the distance they are of pretty poor quality.

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/7.1 ISO-160 1/500 sec. @600mm

7D Mk. 2 + Sigma 150-600 f/5-6.3: f/7.1 ISO-160 1/500 sec. @600mm

In the end they got pretty close. They flew nice and close but it was impossible to get a shot them flying around. At this distance you could see them rummage through the dirt looking for insects. The pictures of them doing that were fairly uninteresting though.

Fuji XE-1 + Sigma 150-600 f/5-6.3: f/7.1 ISO-640 1/500 sec. @600mm

Fuji XE-1 + Sigma 150-600 f/5-6.3: f/7.1 ISO-640 1/500 sec. @600mm

You might have thought they you'd escaped my obsession with infrared photography in this article. Wrong. On this trip I have brought my infrared XE-1 with me to see what I could do with it when trying to take bird photos. This is a dumb idea for many reasons. The first of which is that my telephoto Sigma 150-600 is a Canon EF mount lens. Using it on a Fuji camera means I have no autofocus, image stabilisation or aperture control. Having my monopod with me helped with keeping the lens steady but focusing was a nightmare. The focus ring on the Sigma is abysmal as it offer no ability to finely adjust focus which is so necessary on a telephoto lens with a tiny field of focus. Additionally the viewfinder on the XE-1 is terrible. It is good enough for landscapes when it is easy to nail focus, but here it was impossible to tell when I was or wasn't in focus. The photo above shows off the problems I had with focusing.

Fuji XE-1 + Sigma 150-600 f/5-6.3: f/7.1 ISO-640 1/500 sec. @600mm

Fuji XE-1 + Sigma 150-600 f/5-6.3: f/7.1 ISO-640 1/500 sec. @600mm

Alas I managed to get a good photo. It was a real miracle I did so give the constraints I was operating under. Even better it was the closest a Yellow Robin had gotten to me all day. It is a nice photo, but you wouldn't know it was infrared. Part of my motivation for bringing my infrared camera was too see if there was anything unique about shooting birds in infrared. Turns out there isn't. It looks pretty much like a black and white conversion of a normal photo. Even playing around with doing some false colour yielded poor results. Ah well, now I know.

Now I know

Now I know

Infrared Photography In The Moonlight

Something I've pondered since I converted my XE-1 to infrared has been the possibility of capturing infrared pictures in the moonlight. Most pictures in infrared are taken during the daytime. I've only been able to find a few cases where infrared has been used at night-time and a few rare cases where it has been used with the moonlight (example here). The problem is most infrared shooters use an external infrared filter to capture infrared pictures. Doing this is a cheaper and easier option compared to buying another camera and spending even more money to convert it. The problem with this method is that it requires very long exposure times; usually somewhere between 5-30 seconds and this is in full daylight. At night, when the available light is decreased dramatically, using an infrared filter in front of the lens would require exposures far too long to be practical. Given that, I was still curious to see what infrared photographs would look like in the moonlight.

Before I continue I should dispel a common misconception that infrared cameras are somehow 'night vision' cameras. For the most part the same sources that create visible light also create infrared light and conversely a lack of visible light comes with a lack of infrared light. When people associate infrared with night vision, they are usually thinking of enhanced spectral range or active illumination. Enhanced spectral range just means that the exposure is capturing more than just the visible spectrum of light. This either includes more ultra violet or near infrared light which is useful for night vision because it allows more of the light spectrum to be amplified (more signal). Night vision googles, scopes, etc. like those used by the military use visible and near infrared light for this very reason. Active illumination involves shooting infrared with a source of infrared light to expose the image properly. This is just like using a torch or a camera flash to take pictures in the dark, but it would be a misnomer to call this night vision. The reason why infrared is associated with active illumination/night vision here is because humans and animals can't see infrared light. If you've seen a nature documentary you might have seen footage in black and white at night of animals going about there business. This would have been done by using an infrared camera with active illumination to expose the picture without disturbing the animals. The military also uses this when coupled with their night vision equipment for similar reasons, except this time not to alert people.

From: Michael Nichols at National Geographic.  Link for a brief explanation of active illumination infrared

From: Michael Nichols at National Geographic. Link for a brief explanation of active illumination infrared

Moving back to the main topic, I was still curious how infrared light would behave at night without active illumination. At night the moon reflects light from the sun back to earth and this small amount of light can be used to take interesting pictures. Those familiar with the characteristics of infrared photography know that the reflecting properties of visible light often different dramatically from infrared light. Foliage for instance glows white with infrared white whilst appearing the normal green in visible light. The effect is due to the dramatic increase in the reflecting properties of leaves beyond 700nm although this can vary between species. The curiosity of mine centered around whether moonlight might differ in any way that would impact photography. If the moon didn't reflect enough infrared light for instance, it would make night photography difficult. So I decided to test this out for myself.

The first difficulty of photographing in the moonlight is you actually have to find a night when the moon is out. The moon moves in phases where it is more or less illuminated which in turn influences how much light is reflected back to earth. Ideally the time for moonlight photography would be at a full moon, when the moon is brightest. This narrows the available shooting days to around 5 out of the moon's 30 days cycle. Coupled with the chance of cloud cover it can be difficult to get good conditions to even start taking moonlight photographs. A month ago I managed to find a day when the full moon was out. I grabbed my equipment and headed up on of the local hills to take pictures of the mountains in the moonlight.

Fuji XE-1 + Super Takumar 50mm f/1.4 + Zhongyi Lens Turbo II: f/8 ISO-800 30 sec.

Fuji XE-1 + Super Takumar 50mm f/1.4 + Zhongyi Lens Turbo II: f/8 ISO-800 30 sec.

This first trip didn't turn out well. I had two troubles to do with camera focusing and a light leak. At night there is very little light and looking through the camera's viewer finder reveals a pitch black image. This isn't a problem for exposure because you can do a simple trial and error to narrow down the correct exposure. The big problem is that you can't see what you are taking a picture of and whether of not it is in focus. In this case I was using a manual focus Super Takumar, but if I were using a auto focus lens I would still have to have manual focused because of the lack of light. With visible light you can use the focus markings of the lens to find infinity focus, but because infrared light focuses closer than visible light (a topic I will definitely cover later), that was inaccurate. The Super Takumars are nice in that they have infrared focusing marks, but these were thrown off by my use of a focal reducer. Focusing then was hit and miss as I tried to slightly adjust focus between shots to find the correct position with little success. The focal reducer also created a light leak. I double adapted my m42 lens onto a EF to Fuji X mount Zhongyi focal reducer which works great for normal photography. Double adapting like this isn't ideal and this situation showed off why as the small gap between the m42 to EF adapter and the focal reducer was letting in a some light. This light was showing up in the pictures because the exposure time was so long (30s). Looking at the top left hand side of the picture shows off the light leak. The rest of the image is off focus too.

Fuji XE-1 + Pentacon 50 f/1.8

Fuji XE-1 + Pentacon 50 f/1.8

Despite this setback a month later when the moon returned I set out to try again. This time I traded in my Takumar with a focal reducer for a Pentacon 50 1.8 with a dumb adapter (no elements inside). Removing the focal reducer would remove the source of the light leak, but it would also slightly lower the light getting to the sensor (-~2/3 of a stop). This wasn't much of an issue because I could simply increase the ISO to compensate. The other important thing I did was to put some masking tape over the focusing ring and the rest of the lens when the lens was focused to infinity. I then cut the tape down the middle so the lens could be focused normally. When I needed to focus to infinity in the dark however, all that was required was to line up the two parts of the masking tape. (I switched to the Pentacon from the Takumar because the grip on the Takumar would have been in the way).

Masking tape over the focusing ring. When the two pieces align, infinity focus is achieved.

Masking tape over the focusing ring. When the two pieces align, infinity focus is achieved.

So I set out of a cold winter's evening to get some photos in infrared and here are the results.

Fuji XE-1 + Pentacon 50mm f/1.8: f/1.8 ISO-800 30 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/1.8 ISO-800 30 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/4 ISO-800 30 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/4 ISO-800 30 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/4 ISO-800 30 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/4 ISO-800 30 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/5.6 ISO-200 3 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/5.6 ISO-200 3 sec.

Pretty interesting stuff. All these photos as you'll notice are black and white conversions. Doing false colour infrared conversions adds some interesting detail to the mix.

Fuji XE-1 + Pentacon 50mm f/1.8: f/4 ISO-800 30 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/4 ISO-800 30 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/4 ISO-800 30 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/4 ISO-800 30 sec.

Also so very cool stuff. I should mention though that these pictures were taken not long after sunset. This meant that there was still sunlight coming from behind the mountains. This made colour separation as easy as the normal process. Taking pictures that didn't face the mountains found issues with colour separation. If you look at the following image that faced south rather than west there was some blue separation near the horizon, but further up the sky it started to turn red.

Fuji XE-1 + Pentacon 50mm f/1.8: f/1.8 ISO-800 30 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/1.8 ISO-800 30 sec.

This phenomenon started to occur in the west too as the night went on. The last photo I took which faced west exhibited the same problem.

Fuji XE-1 + Pentacon 50mm f/1.8: f/4 ISO-800 30 sec.

Fuji XE-1 + Pentacon 50mm f/1.8: f/4 ISO-800 30 sec.

This shows that the colour separation ability of infrared was deteriorating. Although red and yellow are different colours, in the separation they are both part of the red channel (720nm really only allows for 2 colour channels, blue and red). What we are seeing is that the infrared light is becoming more uniform as the sun retreats and the moonlight takes over. It might suggest that there is a difference in the infrared light that the moon is sending out compared to the sunlight. This is curious and something I will look into further.

One other thing of note is that shooting wide open (in this case at f/1.8) looked quite nice even though sharpness fell. I think the soft dreamy quality of the focus suits the soft moonlight quite well. (Note: than the exposure has been changed in post so the ISO measure is approximate)

Left: f/1.8 ~ISO 640 30 sec. Right: f/4 ~ISO 2500 30 sec.

Left: f/1.8 ~ISO 640 30 sec. Right: f/4 ~ISO 2500 30 sec.

To conclude it is obvious that you can get interesting photos shooting infrared in the moonlight. In addition shooting wide open creates a nice dreamy effect in the moonlight and false colour infrared becomes difficult as remnants of the sunlight wane. What still isn't clear is why this second phenomenon is occurring. A possible answer is that the moon is reflecting light in a special way, but I can't be sure. I have not doubt in the future I will find myself on top of a hill again trying to answer that question. For now though, this will remain a mystery.

Infrared Photography - The Cure For Haze

Haze is really frustrating. This is not just my personal opinion, but having read countless forum posts about how to reduce haze in landscape photography, it seems to be the consensus. In this context haze refers to atmospheric distortion that affects the image quality of pictures. Haze can refer to different things such as smog or fog, but here the main issue is haze created by a phenomenon known as Rayleigh scattering. Rayleigh scattering (this is a basic, uneducated explanation) occurs when light passes through the atmosphere and scatters when it interacts with particles of gas, water vapour, dust, etc. Rayleigh scattering particularly affects light with a shorter wavelength (i.e. blue light). This scattering gives the sky its blue colour as blue light passing through the atmosphere is scattered whilst other parts of the light spectrum pass with less obstruction. For a proper scientific explanation of Rayleigh scattering check the video below.

Unfortunately Rayleigh scattering doesn't just give us a nice blue sky, it also creates haze in landscape photos. Landscape subjects such as mountains, valleys, rivers, canyons, etc. are typically photographed at a distance; they are too big to do otherwise. This distance introduces scattering as the distance between camera and subject introduces more atmosphere for the light to pass through. Added to this is the changes in the quality of the atmosphere such as dust and water vapour due to weather patterns, bodies of water, time of day, etc. In my experience the most pernicious of these influences is vegetation. Vegetation can influence the water vapour content through dew, but in Australia this is particularly bad because of eucalyptus trees (the most common of trees in Australia). Eucalypts disperse eucalyptus oil into the air which further increases Rayleigh scattering. The Blue Mountains, located on the eastern seaboard, are named after their blue colour created in large part by the large volumes of eucalyptus trees.

Canon 700D + 55-250mm Kit Lens @ 143mm: f/8 ISO-125 1/125 sec.

Canon 700D + 55-250mm Kit Lens @ 143mm: f/8 ISO-125 1/125 sec.

Here is a picture I took a while ago at the Blue Mountains. Notice the blue cast, but also the strong haze effects. This picture shows off the three main problems with haze 1) a lost of detail 2) a loss of contrast and 3) a colour tint (usually blue). Haze is a common problem for landscape photographers around the world, but here in Australia we have it particularly bad due to the abundance of eucalyptus trees. There are some methods to get around haze which usually involve manipulating colours to get rid of the blue tint or increasing the contrast. These solutions are far from ideal and can create images that look unnatural or garish. Here's the last image with Photoshop's dehaze slider set to +40. Not a great result.

Dehaze +40

Dehaze +40

A more perfect solution to this problem comes with infrared photography. Referring back to Raleigh scattering the effects are more severe the shorter the wavelengths of light. Near-infrared (700nm-~1000nm) are the longest wavelengths of light that a digital camera's sensor can detect and are least afflicted by Rayleigh scattering. Getting a camera to shoot infrared is a bit complicated to explain but here it should be sufficient to demonstrate how much difference shooting in infrared makes on haze.

To compare I have two cameras, the Fuji XT-1 and the Fuji XE-1. The XT-1 is a normal visible light camera whilst the XE-1 has been converted to shoot infrared (720nm). Conveniently for this comparison both cameras use the same 16.3 megapixel X-Trans II sensor for an apples-to-apples comparison. Added to this each picture uses the same lens with the same exposure settings of the same scene (taken from a tripod and aligned properly in Photoshop). The only post processing done was to lower the highlights in the visible light pictures and doing a black & white conversion for the infrared pictures.

Fuji XT-1 & XE-1 + Pentacon 50 f/1.8 + Zhongyi Lens Turbo II: f/8 ISO-200 1/500 sec.

Fuji XT-1 & XE-1 + Pentacon 50 f/1.8 + Zhongyi Lens Turbo II: f/8 ISO-200 1/500 sec.

Fuji XT-1 & XE-1 + Tasman 135mm f/2.8 + Zhongyi Lens Turbo II: f/8 ISO-200 1/500 sec.

Fuji XT-1 & XE-1 + Tasman 135mm f/2.8 + Zhongyi Lens Turbo II: f/8 ISO-200 1/500 sec.

Fuji XT-1 & XE-1 + Pentacon 50 f/1.8 + Zhongyi Lens Turbo II: f/8 ISO-200 1/500 sec.

Fuji XT-1 & XE-1 + Pentacon 50 f/1.8 + Zhongyi Lens Turbo II: f/8 ISO-200 1/500 sec.

As you can see the haze present in the visible light pictures is effectively eliminated when the same shot is taken in infrared. This results in an astounding difference in fidelity of the images.

100% crop on the house

100% crop on the house

Cropping in on the picture taken with the 135mm lens furthers illustrates the point. The top image is clear, clean and well defined whilst the one of the bottom is rather ugly and milky.

Clearly infrared has its advantages. These pictures, of a fairly common sort of landscape subject, exhibit haze at levels that is typical for the region (trust me it doesn't get better). Taken in the visible spectrum the pictures are pretty ghastly and even with some time spent cleaning them up, they would only approach the 'ok' territory. The infrared images on the other hand show how much better the scenery looks when the haze is removed. Using infrared sacrifices colour (unless you opt for false colour infrared which is another story) and introduces some of the unique characteristics of infrared like the glowing white foliage. That is a trade off I am more than willing to make given just how bad visible light cameras perform under these conditions.

This is the reason I got into infrared photography in the first place. Australia has some great vistas that look pretty bad when photographed. The Canberra region (where I live) is overlooked by the northern stretches of the Australian Alps and these particular photos were taken at the foothills of said alps. They are beautiful to behold, but only infrared can really do them justice.

 

" only infrared can really do them justice "

"only infrared can really do them justice"