What is it good for?
Hyperfocal focusing, or focusing at the hyperfocal distance, allows you to maximise your DOF and position the Near and Far Limits of your DOF so that all or part of the scene that you are photographing is acceptably sharp.
The Short and Sweet:
If you focus at the hyperfocal distance, then the image will be in focus for half the hyperfocal distance all the way to infinity. For example, if your hyperfocal distance is 5 m, then as long as your focal point is at 5 m from where you stand, your scene will be sharp all the way from 2.5 m to infinity. This is particularly useful in landscape photography, where you often want as much of the scene as possible to appear sharp. You can calculate the focal length and aperture setting for a particular hyperfocal distance with this downloadable hyperfocal chart.
Tell me more:
The hyperfocal distance is quite sensitive, since if you focus only slightly nearer than the hyperfocal distance, then the background in your image can appear too soft. As mentioned in our discussion of DOF , the sharpness of your image falls off with distance from your focal point and is just about acceptable at the Near and Far Limits. If the part of your image that is close to the Near or Far Limit needs to be particularly sharp, you may want to consider focusing at those points and blend the images taken at different focal points.
What is it good for?
The Depth of Field (DOF) is a crucial concept for controlling the part of your image that appears sharp and in focus.
The short and sweet:
Any discussion of DOF has to include two essential points. Note that the DOF is always defined w.r.t your focal point(s):
1) The DOF distance. This is the distance in the scene you photograph which appears acceptably sharp in the final image. Lets say your DOF is 2 m, then the part of your scene that is acceptably sharp will be the 2 m around your focal point.
2) The portion of the DOF distance which extends in front of and behind the focal point, which also may be referred to as Near Limit and Far Limit.
The calculations take into account several factors, including:
2) The distance of your subject from you, i.e. focal point
3) Focal Length
Tell me more:
You will notice that we used the term “acceptably sharp”. This is because the only part of your image that is close to perfectly sharp is that at your focal point.The remainder is blurry but if the blurriness falls below a certain amount, called the maximum circle of confusion, it will not be perceptible to the viewer. This “circle of confusion” depends on two factors, which fall under the discussion of the DOF, and are thus included as points 4 -6.
4) Camera Sensor Size
5) The final size of the displayed/printed image and the distance you are viewing it from.
6) The eye sight of the viewer.
The Near and Far Limits of your DOF are those points where the circle of confusion has reached the maximum size for acceptable sharpness. There thus always is a gradual increase in blurriness (or size of the circle of confusion) as you move away from your focal point.
For other, detailed discussions of DOF please follow this link.
Today was a big day. We were going to fly by helicopter right into the middle of the Tombstone Range. My first time in a helicopter and I sure was excited to set foot in the Tombstone range, the jagged mountains of which we had only seen and photographed from the Dempster highway. We got our backpacks ready, made sure we had all the supplies necessary, and before we were able to take the ride, visited the parks office to brief the staff on what we were going to do and to receive information regarding conditions and regulations. One rather sobering piece of information, was that they were not going to send in a search or rescue party for us if we did not return at our stated time unless we contacted them and asked for help. I sure hoped Marc’s satellite phone was not going to give up on us!
We were flown in in two groups and my group was picked up right on the side of the Dempster highway. Helicopter operators are quite common around this area – it is a profitable, perhaps even lucrative business, due to the needs of mining and tourism operations. Our pilot, an affable Australian, had given us a safety run down, including instructions such as not to walk down hill towards a helicopter when the blades are turning. I suppose these kinds of accidents have happened before! Soon after take off, the vast tundra and pine tree covered hills of the Yukon expanded before our eyes. There were some openings in the cloudy sky and the sun spot lit an already beautiful scene.
PLEASE CLICK TO VIEW LARGE.
However, it was truly breathtaking when we flew over the jagged, razor sharp peaks of the Tombstone range, and a tundra covered valley framed by these stunning mountains opened before us.
PLEASE CLICK TO VIEW LARGE.
We joined the first group which had already arrived, and after the obligatory group picture (which I had insisted on!), we were on our way. With my backpack, I was running camera in hand trying to get some nice pics of the group in action. It didn’t take me long to work up a sweat!
PLEASE CLICK TO VIEW LARGE.
The clouds were ominous and sure enough, shortly after we had started out on our hike, we saw lightning in the distance. Marc was stunned: Lightning in autumn is virtually unheard of, he exclaimed. We put on our rain gear and could see the rain showers quickly approaching us. But rain showers soon turned into a painful wall of wind blown sleet and it was not long before we were wishing for some kind of shelter – unlikely in this tundra covered valley! Yet, there it was: a huge boulder right at the area we were going to camp for the night. We huddled behind the boulder and waited for the storm to let up. But to every cloud there is a silver lining, and not only did the storm let up, the sky opened up too. There was some real promise of wonderful, post storm light, and upon Marc exclaiming ”Let’s do it!” we packed out our camera gear and rushed down to the river and back up a ledge in the search for compositions. The light was changing rapidly and I was trying to incorporate the river in a compelling composition with the dramatic peaks as a backdrop.
PLEASE CLICK TO VIEW LARGE.
I worked my way further up the ledge and began photographing some more dramatic mountain peaks, backlit by the setting sun. Suddenly the remaining storm clouds swooped down and crowned these spectacular mountains in some wonderfully dramatic light. I frantically tried to frame the image the best way I could, given my location, before the beautiful conditions disappeared as quickly as they had first appeared.
PLEASE CLICK TO VIEW LARGE.
Although we had endured some tough conditions, we were also rewarded by some beautiful light. The two tend to go together, but don’t always count on the light following the storm! Exhausted, we trundled back to our campsite to set up our tents and gulp down a delicious dinner cooked up by Marc.
What a day!
A camera’s aperture is the opening through which light, after it has traveled through your camera’s lens, enters the camera body.
The size of your aperture determines:
1)The time it takes for you to expose your image properly
2) The Depth of Field (DOF) of your image, which is the extent to which your image is sharp around the point at which you have focused with your lens.
3) The sharpness of your image, and the ideal aperture size for sharpness depends on the lens you are using.
The aperture size is regulated by a diaphragm, much the same way the eye’s iris functions. One should therefore speak of the effective aperture size.
The opening of the aperture is expressed in terms of an f-number. To calculate the f-number, one takes the ratio of the diameter of the aperture opening to the focal length used. For example, if the focal length of your lens is set at 100 mm, and the diameter of your aperture opening is 25 mm, then the f-number for the aperture is f/4 since 25 mm/100 mm = 1/4. If you reduce your aperture opening to 12.5 mm, but keep the focal length at 100 mm, then the corresponding f number would be f/8, since 12.5 mm/100 mm = 1/8. For the same focal length, an increase in f-number,e.g. from f/4 to f/8, thus corresponds to a decrease in the aperture opening. Alternatively, if your aperture is at f/4 but you change your focal length from 100 mm to 200 mm then the opening of the aperture increases from 25 mm to 50 mm.
From the figure below, you will note that the f-numbers increase by factors of 1.4. The area of the aperture is proportional to the square of its opening,and thus a change by a factor of 1.4 in its opening corresponds to a change of 1.4² = 2 in its area. Each step in the f-number is called an f-stop. If you increase the f-number by one stop, e..g from f/1.4 to f/2,then you are halving the amount of light that enters the camera – this is also called stopping down. This is also where the term f-stop comes from – one stop corresponds to a factor 2 change in the amount of light that enters your camera, and this also corresponds to one exposure value (EV).
Besides controlling the amount of light that enters your camera, the aperture opening is critical to the Depth of Field (DOF) of your image. The smaller the aperture, the greater the DOF and the less blurry your image is around your focal point. However, this can negatively influence the sharpness of your image (not related to DOF), due to an optical effect called diffraction. For each lens, there is a so-called sweet spot aperture opening, where the image is the sharpest. If your aperture is larger than that, the sharpness is negatively affected by aberration effects. If it is smaller than that, the sharpness is negatively affected by diffraction effects.
The ideal aperture for most lenses unfortunately allows for a rather shallow depth of field. However, nowadays one can still achieve almost perfect DOF for rather large aperture openings by being able to blend a series of images taken at different focal points.
For more detailed information, please visit http://en.wikipedia.org/wiki/Aperture
This is my second in a series of posts and images documenting my travels to Canada’s Yukon and the Canadian Rockies.
After a hearty breakfast, we had to wait for the remaining tour participants to arrive in Dawson. Marc had to wade through several urgent E-mails, something he gets the chance to do every now and then when he is back in civilisation. He suggested we visit an area close to Dawson City, which we would have to access via the fittingly named Bonanza Creek road. Dawson City was at the center of the Klondike Gold Rush which lasted only three years (1896-1899). Gold Nuggets were to be found in river beds along the Klondike river and explained the many dredge ponds and huge, antiquated Gold Dredge facilities, which we saw during our drive. In fact, the current high price of gold has made mining here profitable again.
We took a turn into the mountains and soon were surrounded by the most beautiful, lush and colorful autumn foliage. It was early afternoon, and the light not necessarily ideal, but thanks to some spotlighting, and the use of a polarizer and a long lens, I could still get away with some nice images.
Some of the intensely colorful deciduous autumn foliage that covered the hillsides in the vicinity of Dawson city.
We drove further up hill and the vegetation changed to a striking combination of tundra interspersed with pine trees. Encountering this kind of vegetation in the Yukon certainly counts as one of the highlights of my trip. Using a long lens I was able to simplify the scene and isolate the patterns, layers and textures and their beautiful interplay with light. The sloping hill side certainly helped too.
PLEASE CLICK TO VIEW LARGE. Capturing the unique vegetation of the Yukon and beautiful interplay with light certainly counts as one of the highlights of my trip.
We returned to Dawson City to meet up with the remaining participants. Both of them turned out to be medical doctors. Richard was based in Seattle and Mike in Spokane, Washington. We had a short early dinner and Marc excitedly suggested we drive up the Dempster highway to catch the warm late afternoon light spotlighting the foothills of the Tombstone mountain range. And what light it was!
When we arrived, we saw the potential for some great photography. The sky was covered in dark grey clouds, however not continuously, allowing for some dramatic spotlighting of the magnificent tundra covered foothills. We scouted the area in a rush, since we did not want to miss out on the great light. Marc backed his FJ into a particularly promising viewpoint and told us all to climb on top for a better view. Soon there were 6 photographers on the top of a SUV happily clicking away. What a sight that must have been! Since we were obviously not standing on steady ground, there was no point in using a tripod. Fortunately my lens had image stabilisation and using the inverse focal length rule ( Camera shake is barely visible if you expose at a shutter speed smaller than the inverse of the focal length you are using ) I was able to get away with sharp shots which look great when printed large. My long focal length once again allowed me to simplify the scene and I came away with the following image, one of my favourites of the trip.
PLEASE CLICK TO VIEW LARGE. A scene of vast proportions, the foothills of Tombstone National Park’s jagged mountain range, covered in colorful autumn tundra, glow as they are spotlit during a cloudy late afternoon. For a sense of scale, note the pine trees on the second ridge from the front. Tombstone mountain itself lurks ominously in the background, only to be pointed out by a short opening in the sky almost right above it.
We continued snapping away, most of the time not on the roof of the FJ! As we were capturing the beautiful light I looked around (always look around you!), and noticed that behind me the late afternoon sun was spotlighting a hill side painted in colorful tundra. Using my long lens, I was able to simplify the scene into two seemingly counterpropagating elements, with the veins of the hill side pointing to the left ending almost perpendicularly on the diagonal of a downward sloping triangle of dense, intensely colored tundra:
PLEASE CLICK TO VIEW LARGE
It turned out to be a particularly productive day and we were all looking forward to the next day, when we would be helicoptering into the Tombstone range. That night we missed out on the Aurora, again due to the cloudy skies. A sign of things to come?
Thanks for visiting, and perhaps leaving a comment. The next in a series of posts on my travels will be up soon!
I spent the month of September backpacking and camping in Tombstone Territorial Park in Canada’s Yukon Territory (on a photography tour with legendary landscape photographer Marc Adamus ) as well as in the Canadian Rockies. It truly was a magical time. In this series of posts, I would like to share with you the amazing experience I had, illustrated by a number of images which I hope convey the majesty and beauty of the wilderness I had the privilege of exploring.
Travelling to the Yukon, I quickly realized how gigantic and wild Canada is. Soon after my flight left from Montreal, I found myself looking down in wonder on an unbroken landscape of thousands of lakes and forests. No sign of civilization, a dream come true. I always wondered what North America would have looked like before anybody settled it – and there it was! I was amazed by how close this wilderness was to a major city like Montreal.
The flight from Montreal to Calgary, both cities significantly inland, took around 4 hours. To put this in perspective, flying from New York City to Seattle takes around 3 hours, and the United States is no small country! During the last leg of my flight, from Vancouver to Whitehorse in the Yukon, I found myself looking down on eternal, unbroken, wild coastal mountain ranges, some of their peaks sticking out above the cloud cover -an awe inspiring sight. Canada is not only gigantic, but it also is one of the very few remaining countries where the majority is wild and virtually untouched, by some estimates as much as 80%.
In Whitehorse, I met up with another participant, Nagesh Mahadev. Nagesh hails from India, lives in mild weathered Texas, has never been on a backpacking trip, and decided to jump in at the deep end – we struck it off immediately. The following day we finally met Marc – a man of slender build and not that tall – certainly belying the strength and endurance of someone who spends the majority of his time hiking huge distances, camping under abhorrent conditions, all at the same time carrying backpacks at least 80 lbs in weight. We shared a ride to the town we would use as our base, Dawson city, in his growling, custom modified Toyota FJ Cruiser. The car was scratched and quite beaten up, especially so considering that it was only a little more than a year old. Marc’s philosophy, he told us, is that his car simply is a tool for his many trips and expeditions, and he did not concern himself with things like resale value. The drive was a taste of things to come – a vast, virtually uninhabited landscape of hills covered in boreal forest and wonderfully colorful tundra. This combination of elements was particularly striking- something I had never seen before, and very photogenic too.
An aerial image of the landscape so typical of Canada’s Yukon Territory. A vast, virtually uninhabited landscape of mountains and hills covered in tundra and pine trees. Note the road that meanders alongside the river through this image – the so-called Dempster Highway, in the vicinity of our base town, Dawson City.
Marc shared many a story of his travels and experiences, especially the crystal clear, blue colored ice caves he encountered on his month long solo backpacking trip through Alaska’s and British Columbia’s Boundary range, which he had just returned from. He is also planning to photograph the towering mountains of Baffin Island in 2013, and was wondering how he would be able to bring in a shot gun, for any aggressive polar bears he might encounter. We were joking that Marc was on his way to becoming one of the prolific documenters of Canada’s wilderness, and yet he lives in the United States!
The spectacular and unique combination of tundra, shrubs and pine trees is part of what makes the Yukon so special to me.
As we were approaching Dawson City, Marc excitedly pointed out snow on the distant mountains - a promising indicator of snow covered mountain tops in Tombstone Territorial Park, our final destination. Since snow is such a great reflector of light, this would make it much easier to maintain detail in the landscape when photographing the Aurora at night. We finally arrived in Dawson City and it immediately struck us as a Wild West Town straight out of the movies. Sand roads, the architecture and some very dodgy bars with even more sketchy characters languishing outside. The first night we went out on the s0-called Dempster highway, in search of compositions to keep in mind should the Aurora materialize. When shooting the Aurora, so Marc told us, one needs to scout for good compositions during the day so that one can settle in on a chosen composition during the night,and wait for the Aurora to appear above. Unfortunately it was cloudy that night but that did not prevent us from enjoying an evening of surprisingly good food and beer at our hotel’s restaurant, the aptly named Eldorado.
Thank you for visiting. Part II will follow shortly!
Well, after some extensive research I finally have purchased a new camera . My trusty Canon 5D now is more than 6 years old and besides the fact that, after a few hard falls, it is about to draw its last breath, there is also some amazing technology out there which greatly expands what is doable and opens up a whole world of creative opportunities.
For me, one of the most important developments is the ability to shoot relatively clean images at very high ISO (film sensitivity), something which would have been unthinkable 5 years ago. This has resulted in a surge of night photography where spectacular images of the milky way abound. The sensitivity of the sensors is so high, and the noise so low, that taking high ISO images for as little as 10 s reveals detail not visible to the eye. In addition, a 10 s exposure is short enough for the motion of the stars to be imperceptible – no more need for star trails!
Nikon originally priced their D800 at $ 3000 as compared to the $ 3500 5D MK III. The price for the MK III has now dropped to around $ 3000. The D800 boasts a substantially higher pixel count, 36 MP vs 22 MP, thus catapulting it into the domain of medium format cameras. Its high dynamic range (the amount of separation between highlights and shadows it can capture without blacking out the shadows or blowing out the highlights) is comparable to the MKIII, it has very good high ISO performance, only slightly less than the MKIII, and it excels in shadow noise (the amount by which one can boost the exposure in the shadows in postprocessing without introducing excessive noise). In addition, the best ultrawide lens out there is the Nikon 14-24 and when used with a Canon, the automatic functions such as exposure and focus do not work.
So I chose the D800, right?
The D800 is too slow for my purposes. I like to shoot wildlife and I am constantly adding to my adventure portfolio. This often requires shooting many frames at as high a rate as possible. The relevant technical citeria for this would be the burst rate (the maximum number of frames per second), the number of frames until the camera’s buffer is full, the burst rate when the buffer is full, and, very importantly, the time it takes for the files to be written to the memory card and the buffer to clear out. It is in the two latter criteria where the MKIII truly excels: The time for files to be written to memory is 4s for the MKIII compared to 21 s, and the frame rate at full buffer is 2.7/s continously while that of the D800 is 1/s for 3 shots before one has to wait another 0.9s to repeat. For full details, please see the test results for the MKIII and the D800. I have often been in situtations where I had to wait several seconds before I could shoot again at the full rate, and by that time the scene I wanted to capture would already be over.
Choosing between the D800 and MKIII was not easy, but the MK III clinched the speed category by a long shot. The reduced price helped too!
In this post, I will write about what I feel is one of the main strengths of digital photography: Exposure blending. As we know, the digital sensor/photographic film can capture both shadow and highlight detail as long as the range in exposure values falls within its dynamic range. In cases such as sunrises or sunsets, with the sun included, this is almost never possible. In those cases, if exposing for the sun, shadows will be blacked out and detail lost, while exposing for the shadows, the sun will be blown out.
Although a significant number of digital and, by implication, film camera users, swear on Neutral density gradient filters (NDGs), I prefer exposure blending in most cases, since I feel it gives the photographer a much richer tool set for technical perfection and creative outlet.
I prefer exposure blending for two reasons:
1) Mind the line: No transition lines/obviously darkened areas of the image. Although NDGs keep exposure in check, in tricky scenes, which arise surprisingly often, the NDG line (the border between coated and uncoated regions of the filter) may be obvious in the final image. This is especially so for hard stop NDGs. These lines can be very hard and time consuming, if not impossible, to remove in post processing. Alternatively, you would have to be very skilled, since such lines could be avoided with 2 or 3 carefully arranged NDG’s, a time consuming effort. With exposure blending one can carefully combine exposures that were taken. One only needs to use the proper masks (which will be a topic of future posts). I manually blend my images and avoid the HDR approach, which in my opinion is seriously lacking, especially for landscapes.
2) Chase the light: With transition lines no longer a worry, you can now follow rapidly changing light conditions from different vantage points and with varying compositions, and still end up with technically excellent images. You won’t loose out on precious seconds of beautiful light as you fidget around with filters. You only need to ensure that the highlights and shadows are captured in correctly bracketed exposures, which can easily be checked with the exposure histograms on your camera LCD. The uninitiated will be pleasantly surprised by how rapid and simple this procedure is.
The two images below illustrate particularly tricky scenes which I was able to capture within a matter of seconds, allowing me to move on to the next subject/composition, and still come away with technically sound images. This would have been very difficult and lengthy, if not impossible, to achieve with NDGs, unless I was happy with some fat transition line through my work.
The image above was taken on the frozen shores of Lake Ontario, Canada. This scene had a rather high dynamic range, from shadows within the “ice cave” to strong highlights associated with the rising sun and the bright snow. Had I used a NDG to keep the sky and shadows in check, a transition line likely would have passed through the top of the cave and/or part of the frozen lake surface. Instead, I took three exposures to capture the dynamic range, and then was able to blend these images with suitable masks in a way which I felt best reflected the scene as I remembered it.
The second image, above, is an image of High Falls on the East Side of Algonquin Provincial Park in Ontario, Canada. This scene exhibited an extreme dynamic range, since it was taken in the late afternoon when the sun was still strong, and a number of areas in the image were in deep afternoon shadows. In this case, a strong NDG filter would have put parts of the trees on the top of the waterfall in deep shadow and artificially darkened the sky, just to keep the sun in check. The transition from the lighter bottom part of the trees to the darker top part would have been particularly obvious. In this image I blended only two exposures, but had to double process one exposure and tripple process the other. Although it was a lot of work, it certainly was worth it!
There are however cases where blending exposures may not be the best approach. When bracketing for exposure, images are taken at different points in time. This is problematic if there are areas of the image which incorporate moving objects and which need to be blended. Typical examples would be moving clouds or water; even a lake’s shimmering surface would be a case in point. For this a NDG comes out tops, since the exposure is kept in check in one single shot.
A strength of the NDG that is often overlooked, is the fact that it reduces flare in the camera. By flare I do not mean the obvious streaks or lines that are introduced, but the more subtle aspect of light bouncing around in the lens, thereby reducing contrast and sometimes seemingly changing the color temperature of the scene – light will appear a lot warmer than what it actually was. This can happen even if the sun is not included in the scene. The photographer will place the darker areas of the NDG over the brighter region of the sky and thereby will reduce the total amount of light hitting the lens, reducing flare. With exposure bracketing one needs to be particularly careful, since when one exposes for the shadows a large amount of light from the brighter part of the scene will enter the lens and thereby introduce flare, even in the shadows! One should shade the lens from the brighter part of the sky with one’s hand (flare caps as supplied by lens manufacturers are in my opinion quite useless), and then blend accordingly. If there is flare, the effect of blocking out the light can easily be seen in the view finder. The image below is an example where I used my hand to block out the sun when exposing for the shadows.
The image above is a view, taken in later afternoon, of islands surrounding the Greek Island Amorgos, which forms part of the Cyclades in the Mediterranean. This also is a blended exposure. However, when exposing for the foreground, a significant amount of light from the setting sun entered the lens and introduced flare throughout the image. This killed the contrast necessary to convey the beautiful golden glow on the foreground shrubs. By shielding the lens from the sun (this meant my hand was blocking the top part of the image), I eliminated flare, and by blending with an exposure for the sky and sun I was able to realize this image. In future posts I will describe in detail how this image came about.
That’s all for this post. In the next series of posts I will give some examples of manual blending, mask generation and will introduce the reader to an extremely powerful tool, luminosity masks.