Contact

Name

Email *

Message *

Sunday, October 15, 2023

A strange phenomenon

The other day I happened to come across profile of a fellow bird photographer who has mentioned a quote by Magnum Photographer Inge Morath as having said, “ Photography is a strange phenomenon, you trust your eye and cannot help but bare your soul”. Yes, we trust our eyes without paying too much attention to technical issues as these can interfere with creative aspects. No doubt a good photographer makes image with his feelings and some images do touch our soul.

Inge Morath has rightly mentioned her feelings, but her emphasis on trusting our eyes made me ponder over a question does camera sees more than our eyes. If so, how and why. The answer to this question holds more significance for bird photographers and birders who keenly observe not only behaviour and anatomy of birds, but also their morphology.

An inquisitive mind may question similarities as well as differences between the camera and the human eye. Those who have better understanding of functions of optical devices also know that camera sees more than the human eye.

I have seen many birders who first see birds with their bare eyes, then through their binocular or monocular and then make a ‘record’ photo of the bird with the help of a long lens in the given situation so as to observe and study bird’s distinctive markings. They all understand that bare eyes or say ‘unaided eyes’ need modern gadgets to see beyond their limiting factors.

The technology is fast developing thus widening the gap between the functions of human eye and the camera. While the human eye has always remained as such, the technological developments that have taken place since the invention of camera obscura have unfolded a whole new world of visual media. This process is unending and future inventions may be more startling.

When we capture an image, only a visual record is made, which is flat and has  two dimensions, but when we see the visual impact remains in our memory for a longer period of time and is of three dimensions-- length, height and has depth of field. Also, a camera can create a brighter picture as it has the potential to collect light for a longer period.

We all know both the eye and the camera have a lens and both receive light through an aperture device.  They also have a method to interpret that light as an image. In camera we can adjust light through aperture, automatically or manually whereas eyes have pupil, a round area in the iris, which controls light. In both, the camera and our eyes, the light and image are inverted by the receiving mechanism.

In eye, light is received by retina, which is almost of the same size of  sensor of a full frame(35mm) camera and is an extension of brain. Light is transmitted to the back portion of brain and image is perceived. It is because of curvature of retina that its edges are about the same distance from the lens as the center. Therefore, unlike camera lenses, the retina has corner sharpness and we also see more in corners. On the other hand the flange distance, the space between where the lens is mounted to the camera body and to the camera’s image sensor, is comparatively larger. The shorter a flange distance, the smaller and lighter a camera body can be. The mirrorless cameras have, therefore, shorter flange distance thus are lighter and smaller than the DSLRs.  In case of lenses generally the corners are not as sharp as the center of an image is.

The question remains why camera sees more than our eyes. We know the camera sends every pixel data from sensor to the computer which may result in certain distortions like barrel distortion, colour variation and vignetting. Contrary to it, eyes are not so capable because data passes through optic nerve. Eyes adjust their sensitivity to see naturally, but cameras have a feature to adjust ISO manually or let it get adjusted automatically.

Camera sensor has regular grid of pixels with every square millimeter having exactly the same number and pattern of pixels. In cameras the field of view depends on the kind of lens. On the other hand, retina, a small central area of about 6 mm, has dense concentration of photo receptors. Interestingly this portion has best resolving ability than any camera.

Although our peripheral vision has high refresh rate, our eye is sensitive to moving objects, but has not much resolution to read letters. The focal length of the human eye is the distance between the retina and the eye lens and this focal length varies from person to person. Not many know that 50 mm camera lens closely matches the human eye as the angle of view created by the 50 mm focal length is almost the same as the viewing angle of the human eye. The built-in technology of eye can’t match the ever-improving modern technology of camera.

The old saying goes, ‘eyes are the windows to the soul’. Photography makes us trust our eyes, but it is also such a magical phenomenon where silence speaks louder than words. At times its sound is more deafening than words. Let’s keep enjoying the sound of silence of this strange phenomenon of photography.

As I conclude, I am reminded of another female photographer, Maggie Steber, who has also rightly said, “The camera can open many doors, but sometimes you need to put it down and live."

--Subhash Sapru

 

 

 

 

 

 

 

 

 

Monday, March 7, 2022

MIRROR TO MIRRORLESS

 

The ongoing transition from DSLR to the mirrorless may be gradual, but it reminds of the earlier transitions, especially of “manual” to “auto focus” and “film” to “digital”. While both the “manual” as well as  “film” are still being accepted and used, they are now more of a hobby. Technology keeps rolling out new developments and many innovations get accepted. Reports indicate that Canon no longer intends to produce any more flagship DSLR and Nikon has discontinued its popular D500 and no replacement has been announced.

In the recent years, the mirrorless cameras have undergone tremendous technological improvement that has given push to the camera market thus setting the pace for gradual phasing out of DSLR cameras. But this hard task master will not die at least in the near future. Let’s try to understand how good is the mirrorless, especially for wildlife photographers, who like photojournalists often question its parity with the one they have been using with trust for decades. They have accumulated an array of lenses and accessories for their DSLRs which would be hard to part with.

One of the basic observation is that  it is easy to switch from a Canon or Nikon or  any other DSLR brand to its mirrorless sibling because the menu is structured in their well-known  style with almost similar buttons as previous cameras. Therefore,  finding and using the basic functions takes hardly any adaptation time. However as mirrorless camera offers quite a few more functions and options. To some the menu may be slightly different and a little hard to find a few of its functions.

The latest mirrorless cameras are packed with a lot of new and impressive features into their rugged  bodies having drip and dust resistance. They can also be operated in extremely low temperature. Now these cameras are up-to-date in every aspect. Like a smart phone, we can easily touch their screen to focus on our subject. The Wi-Fi and Bluetooth features make it easy to pair these with other devices such as smartphones to transfer large amounts of data without any wire.

Although both the DSLR and the mirrorless cameras do differ in their construction and design, yet they have similar sensors, image quality, technologies and basic features. With removal of mirror and prism, camera size and weight have been considerably reduced. Those who are used to bigger size of camera bodies to handle long lenses may find these smaller bodies inconvenient, especially if they have to wear gloves. Adapters are available for mirrorless systems so that photographers  are able to use most of their SLR lenses with full autofocus and aperture control.

In both the DSLR and the mirrorless  cameras, we see through the lens, but they have different ways to show us how will be the image. In DSLRs the optical image is reflected by the mirror and we see it through the view finder. With the release of shutter, the mirror flips upward and sensor gets exposed to the image. On the other hand, mirrorless camera being without a mirror, a live view is created and we see the image either on back screen or through the Electronic View Finder (EVF). Nowadays the EVFs are much improved with high resolution and clarity of the optical view finder. The fast refresh rate has eliminated viewfinder lag to quickly follow moving subjects. The blackout effect that we used to see while shooting continuous bursts of images is now a thing of the past. In a mirrorless camera, what we see in EVF is what we get.This  ability to see our exposure while composing an image is a significant advantage of these cameras. It also enables us to see in real time how our settings change our exposure, depth of field and more. If required, changes can be applied instantly while looking through the viewfinder. It is something optical viewfinder cannot do. The EVF is good enough to show a more clearly visible view of a scene even in low light.

The autofocus system too has been further improved and its features either match or surpass DSLRs for autofocus speed. Although the DSLR cameras are fast yet the focusing speeds on most mirrorless camera can be just that bit faster. This comes down to the fact that mirrorless cameras use many more focus points than DSLRs. In the absence of mirror, they can read sensor while performing autofocus and this is a significant advantage. Therefore, mirrorless camera’s focus is more accurate than DSLR. Also, they neither suffer from lens alignment issues nor back or front focusing issues. The Face/Eye Detection AF and Animal Face/Eye-Detection AF  are interesting features. Unlike the DSLRs, the AF sensors in mirrorless AF systems can go right upto the edges of the frame. When live-view is engaged in a DSLR, it behaves the same way as a mirrorless camera, but does not always have the same features of a mirrorless.

Before you go in for a mirrorless camera, its better to ensure that it has no trouble in achieving subject auto focus that is  AF-C in low contrast situations. Although many new mirrorless cameras have quick start up and no viewfinder blackout, yet some  mirrorless cameras take a moment to start up. It can be half a second or so to come out of standby mode.

A more prominent feature of mirrorless cameras is the responsiveness of the shutter release button. These cameras instantaneously capture photos as there is no mirror to move out of the way when the shutter release button is pressed. This is useful especially in capturing fast action, such as a fast  flying bird or any other fast action taking place. Their frame rate is also very high and the silent mode is appreciably silent. Some mirrorless cameras can record 10-bit 8K UHD video at 24, 25 or 30 FPS for extended period of time, which can be two hours in some cameras. So is the capability of sustained fast continuous shooting bursts with very high FPS  burst speed for both JPG and RAW files.

As compared to the DSLRs, the  size and life of a mirrorless  camera battery is short. The  functions like LCD display or the electronic viewfinder and built in image stabilization in camera bodies make them dependent on battery. When using long lenses, their long focal length having larger and heavier focusing elements, require a lot more power to move than the typically smaller and shorter focal length lenses. The best solution is to keep extra batteries in your bag. Some mirrorless cameras support USB charging thus having  the advantage of charging the battery  within the camera body. For this there are three options to charge--with a wall plug or a power bank or with a computer.

The wildlife photographers and photojournalists look for parity of the mirrorless cameras with the DSLRs. The hard core DSLR users may feel that the mirrorless has neither yet replaced the DSLR nor has fully reached parity with it. For many their concern is availability of lenses and focus performance while tracking subjects. The fact is they have not only attained parity, but have even surpassed the DSLR in some significant areas. Therefore, you aren’t losing out in any way if you opt for a mirrorless camera. This replies the much talked about question “does mirrorless holds key to the future”, ‘yes’ future belongs to the mirrorless.   

DSLR Camera
DSLR Camera


Subhash Sapru
Mirrorless Camera

*******

 

Sunday, January 9, 2022

Why some birds roost in peg-legged stance ?

 



Its common to see some birds relaxing or sleeping on one leg. But why ? This simple question had always baffled me till I took to bird photography seriously and began to observe their behavior. I remember in childhood whenever I asked the elders that why birds, especially egrets  stand of one leg, pat would come the reply, “its prayer time”. During my recent visit to Siswan dam, I saw a large number of Ruddy Shelducks basking while standing on one leg. Now I know these species  understand  better why to relax on one leg. They seem to be aware that they have adaptations to manage heat loss.

We all know most of  the birds have naked legs without insulating feathers. Their feet being closer to environmental temperature, they don’t lose as much heat as they would if they were at body temperature. The widely known theory is that by standing on one leg, they conserve heat and prevent at least it from heat loss. A bird with its one foot tucked up reduces by half the amount of heat lost through its unfeathered  limbs. In other words, the arteries that transport blood into the legs of birds are in contact with the veins that return blood to their heart. The warm arteries heat the cooler veins which also cool the arteries. Also, during winter some species  flutter  their feathers to cover both legs. Interestingly, to get extra warmth, they tuck their beaks under their shoulder feathers, but not under their wings.

Ever thought what makes birds comfortable in this posture of standing on one leg for a long time. Birds don’t have muscles in their feet or legs. Each of their leg has two flexor tendons that run from shoulder to the toes. With change in angle of their ankle they are able to close and lock their feet around a perch. Therefore they are able to sleep while standing on one leg.