Aperture?

Aperture is one of those words that scares a lot of people. It’s something that a lot of us know is there but don’t want to deal with. After all, that’s why we bought an automatic camera. But aperture is something that every photographer should be aware of, amateur or not. It is one of the cameras functions that set out limitations for every photo we take.

The aperture in a camera is a function of the lens. It works the same way that the iris of our eye works. If you haven’t already experienced this phenomenon in science class then grab a flash light and go to a mirror. First turn out all the lights and wait for a few seconds. Turn the lights back on and look into the mirror. Your pupils should be wide open. Now, quickly, shine the flashlight right into your eyes. The pupils will close up pretty quick. This is because your eye is monitoring how much light it lets in, taking only what it needs.

This is the exact primary function of a lens’s aperture. An automatic camera will have a light sensor that measures how much light is entering the lens. In a situation where there is a lot of light it will close the aperture to a finer point because it doesn’t want to over expose the picture. For photos taken in doors or even at night, the aperture will be opened up.

This function of the aperture works hand in hand with the camera’s shutter. Imagine that the camera has an option to keep the shutter open—thereby exposing the film or CCD to light—for anywhere from a hundredth of a second to an entire second. That means the shutter can open and close really fast or really slowly. If too much light enters the camera during any one of these scenarios the picture would be exposed too much. Now let’s get back to the aperture. If the camera’s aperture is opened wide then a lot of light can get in and the shutter won’t have to be open as long. Conversely, if the aperture is closed to a fine point then not as much light gets in and the shutter will have to be open longer.

Before the days of automatic exposures a photographer had to do a bit of math to determine the best way to balance these things. These days the camera does most of the work for you. But it isn’t always right! Why? Because the aperture also affects the focus.

Imagine a billion rays of light racing into a lens. The narrower the opening, the more focused those rays will become. In practical terms this means if you took a picture of a person with a wide open aperture then the person may be in focus, but everything in front of them and behind them may be blurry. The more the aperture is closed, the finer the light entering the camera becomes and, in turn, more things get focused. All of a sudden the person is sharp as is the fence behind them and the tree, etc.

The aperture, therefore, acts as both a technical means of taking a photo and a way of adjusting the pictures aesthetics.

Note as well that in photography the aperture is represented by numbers known as F-stops. The higher the F-stop is, the more the aperture is closed.

Assignment #3 Colors

Our third assignment was themed as "Colors". Time for my trusty Nikon D40x, nikkor 18-135, extension tubes , table lamps, and DIY product table again!

First trial using jelly beans and sunflower seed chocolates

Jelly beans

Sunflower seeds (chocolate costed nuts) They are about
half an inch in length.

Combination on jelly beans and sunflower seeds

My final edition of jelly beans. I used the focusing in-out technique to get this
effect. You use a slow shutter and pre-focus on the subject.
Focus it in (Max focus) and click the shutter. Now while
waiting for the shutter to close you smoothly focus out until the shutter closes.
The jelly beans here were placed on top of a bond paper
on a glass table and I placed a table lamp under it and another one on top.
I won 2nd place here. :)

Assignment #2 Motion

Our professor asked us to shoot something in motion or freeze a motion. It took me quite some time to decide what to take. So I decided to shoot water droplets. So I took my Nikon D40x with 18-135mm and manual extension tubes I also got my trusty table lamps again and my daughters writing table and put it in front of our ref. My wife saw me when she got home and laughed at me and said I'm crazy! hehehehe! Don't have the budget to buy a decent product table but I believe it's really not the equipment to get great photos (although it really helps!) but the eye and imagination of the photographer that captures great photos!

My set-up! My own DIY product table. Our ref as my backdrop.

My first trial and didn't quite like it! :(


My final and winning shot! I won in our class! :)

Assignment #1 of my Photography workshop

Our professor gave us the theme "Single Light source" as our first assignment.

This was the set-up of my assignment. I was holding the table lamp
while my camera was on my tripod. I inserted the carton of our
toilet paper (the circular one that we usually imagine when we were
kids that it's a telescope :)) to the table lamp bulb to concentrate
the light. I used the glass table to reflect the subject (fruits) and put
a black thingy below the table for added reflection.


My final image entitled "In the Middle". There's no post processing
done here. What you see is the shot I took direct from the camera.
I got a special mention in class and won a photography magazine. :)

Concept of Permanent Photos

Conception of permanent images

A camera obscura box used for drawing images

Photography is the result of combining several technical discoveries. Long before the first photographs were made, Ibn al-Haytham (Alhazen) (965–1040) invented the camera obscura and pinhole camera, Albertus Magnus (1139-1238) discovered silver nitrate, and Georges Fabricius (1516-1571) discovered silver chloride. Daniel Barbaro described a diaphragm in 1568. Wilhelm Homberg described how light darkened some chemicals (photochemical effect) in 1694. The fiction book Giphantie (by the French Tiphaigne de la Roche, 1729-1774) described what can be interpreted as photography.

For centuries, images have been projected onto surfaces. According to the Hockney-Falco thesis as argued by artist David Hockney, some artists used the camera obscura and camera lucida to trace scenes as early as the 16th century. However, this theory is heavily disputed by today's contemporary realist artists who are able to create high levels of realism without optical aids. These early cameras did not fix an image, but only projected images from an opening in the wall of a darkened room onto a surface, turning the room into a large pinhole camera. The phrase camera obscura literally means dark chamber. While this early prototype of today's modern camera may have had modest usage in its time, it was an important step in the evolution of the invention.

History of camera and Digital Photography

History of the camera

Camera obscura

The first permanent photograph was made in 1826 or 1827by Joseph Nicéphore Niépce using a sliding wooden box camera made by Charles and Vincent Chevalier in Paris. Niépce built on a discovery by Johann Heinrich Schultz (1724): a silver and chalk mixture darkens under exposure to light. While this was the introduction of photography, the history of the camera itself can be traced back much further. Photographic cameras were a development of the camera obscura, a device dating back to the Book of Optics (1021) of the Iraqi Arab scientist Ibn al-Haytham (Alhacen), which uses a pinhole or lens to project an image of the scene outside onto a viewing surface.

Before the invention of photographic lapel processes there was no way to preserve the images produced by these cameras apart from manually tracing them. The earliest cameras were room-sized, with space for one or more people inside; these gradually evolved into more and more compact models such that by Niépce's time portable handheld cameras suitable for photography were readily available. The first camera that was small and portable enough to be practical for photography was built by Johann Zahn in 1685, though it would be almost 150 years before such an application was possible.

Digital Photography

The charge-coupled device (CCD) was invented in 1969 by Willard Boyle and George E. Smith at AT&T Bell Labs. The lab was working on the Picture-phone and on the development of semiconductor bubble memory. Merging these two initiatives, Boyle and Smith conceived of the design of what they termed 'Charge "Bubble" Devices'. The essence of the design was the ability to transfer charge along the surface of a semiconductor.

• 1973 - Fairchild Semiconductor releases the first large image forming CCD chip; 100 rows and 100 columns.
• 1975 - Bryce Bayer of Kodak develops the Bayer filter mosaic pattern for CCD color image sensors
• 1986 - Kodak scientists develop the world's first megapixel sensor

Taken from Wikipedia.

Camera shutter

Camera shutters can be fitted in two positions:

• Central shutters are mounted within a lens assembly, or more rarely behind or even in front of a lens and shut off the beam of light where it is narrow. A leaf mechanism is usually used.
• Focal plane shutters are mounted near the focal plane and move to uncover the film or sensor.

Shutters immediately behind the lens were used in some cameras with limited lens interchangeability. Shutters in front of the lens were used in the early days of photography.

Focal-plane shutters are usually implemented as a pair of cloth, metal, or plastic curtains which shield the film from light. For shutter speeds slower than a certain point (known as the X-sync speed of the shutter),which depends on the camera, one curtain of the shutter opens, and the other closes after the correct exposure time. At shutter speeds faster than the X-sync speed, the top curtain of the shutter travels across the focal plane, with the second curtain following behind, so that each section of the film or sensor is exposed for the correct amount of time. The effective exposure time can be much shorter than for central shutters.

Focal plane shutters have the advantages of enabling much shorter exposures, and allowing the use of interchangeable lenses without requiring the expense of a separate shutter for each lens. They have the disadvantage of distorting the images of fast-moving objects: although no part of the film is exposed for longer than the time set on the dial, one edge of the film is exposed an appreciable time after the other, so that a horizontally moving shutter will, for example, elongate or shorten the image of a car speeding in the same or the opposite direction to the shutter movement.

Other mechanisms than the dilating aperture and the sliding curtains have been used; anything which exposes the film to light for a specified time will suffice.

The time for which a shutter remains open, the exposure time, is determined by a timing mechanism. These were originally mechanical, but since the late twentieth century are mostly electronic.

The exposure time and the effective aperture of the lens must together be such as to allow the right amount to reach the film or sensor. Additionally, the exposure time must be suitable to handle any motion of the subject. Usually it must be fast enough to "freeze" rapid motion; sometimes a controlled degree of blur is desired, to give a sensation of movement.

Most shutters generate a signal to trigger a flash, if connected. This was quite a complicated matter with mechanical shutters and flashbulbs which took an appreciable time to reach full brightness, but is simple with electronic timers and electronic flash units which fire virtually instantaneously. When using a focal-plane shutter with a flash, a photographer will typically operate the shutter at its X-sync speed or slower; however, some electronic flashes can produce a steady pulse compatible with a focal-plane shutter operated at much faster shutter speeds.

Cinematography uses a rotary disc shutter in movie cameras, a continuously spinning disc which conceals the image with a reflex mirror during the intermittent motion between frame exposure. The disc then spins to an open section that exposes the next frame of film while it is held by the registration pin.

Leaf shutters

A leaf shutter is a type of camera shutter consisting of a mechanism with one or more pivoting metal leaves which normally does not allow light through the lens onto the film, but which when triggered opens the shutter by moving the leaves to uncover the lens for the required time to make an exposure, then shuts.

Simple leaf shutters have a single leaf, or two leaves, which pivot so as to allow light through to the lens when triggered. If two leaves are used they have curved edges to create a roughly circular aperture. Simple leaf shutters typically have only one shutter speed and are commonly found in disposable cameras and cheap point-and-shoot cameras. Some have more than one speed.

Simple leaf shutter
(1. Shutter plate
2. Aperture covered by leaf shutter
3. Aperture during exposure
4. Leaf blade
5. Catch mechanism
6. Butterfly spring)

The main advantages of the leaf shutter are:

• Relatively simple construction is possible.
• No cocking mechanism
• Simple to use as the shutter speed is fixed
• Less costly than a focal plane shutter or diaphragm shutter
• Flash synchronization possible at all speeds.
• Small size is achieved by placing the shutter at the focal convergent point either inside the lens or inside the camera body.

Some of the disadvantages of the leaf shutter are:

• Shutter speeds are limited to 1/500th or 1/250th of a second.
• In practice speeds of these inexpensive shutters may be inaccurate

Diaphragm shutter

One diaphragm shutter opening over another in an Akarex camera

Entries in Cassell's Cyclopedia of Photography, 1911. The terminology diaphragm shutter has since fallen from common use.

A diaphragm shutter is a type of leaf shutter consisting of a number of thin blades which briefly uncover the camera aperture to make the exposure. The blades slide over each other in a way which creates a circular aperture which enlarges as quickly as possible to uncover the whole lens, stays open for the required time, then closes in the same way. The larger the number of blades, the more accurately circular is the aperture. An odd number of blades is usually used: 3, 5, or more.

The term diaphragm shutter has also been used to describe an optical stop with a slit, near the focal plane of a moving-film high-speed camera.

Central shutters

A central shutter is a camera shutter normally located within the lens assembly where a relatively small opening allows light to cover the entire image. The term is also used for shutters behind, but near to, the lens. The alternative to a central shutter is a focal-plane shutter.

Interchangeable lens cameras with a central shutter within the lens body require that each lens has a shutter built into it. In practice most cameras with interchangeable lenses use a single focal plane shutter in the camera body for all lenses, while cameras with a fixed lens use a cheaper central shutter.

Film cameras, but not digital cameras, with a central shutter and interchangeable lenses often have a secondary shutter or darkslide to cover the film and allow changing lens in mid-roll without fogging the film.

Central shutters usually use either the simple leaf mechanism or the superior diaphragm mechanism.

The main advantages of the central shutter compared to a focal-plane shutter are:

• Relatively simple construction is possible.
• Less expensive to produce than a focal-plane shutter.
• Flash synchronization is possible at all speeds because the shutter opens fully.
• Small size is achieved by placing the shutter where the bundle of rays is smaller, either inside the lens or inside the camera body.
• Many versions have no connection between the cocking mechanism and the film advance mechanism, making multiple exposures possible.
• Generally much quieter operation because of fewer and less bulky moving parts
• More realistic photographs in high speed follow-through—lateral focal plane shutters compress or elongate the image in such cases.

Some disadvantages of the central shutter are:

• For an interchangeable lens system, each lens has to have a shutter built into it.
• Leaf shutter speeds are limited by the speed at which the leaves can move: normally 1/500th of a second for a diaphragm shutter and 1/125th of a second for a simple leaf shutter.
• Some versions may have no connection between the cocking mechanism and the film advance mechanism, making accidental multiple exposures a common problem, although this is a feature of camera manufacture rather than the shutter itself.

Shutter lag

Shutter lag is the time between pressing the shutter release and the camera responding by taking the picture. While this delay was insignificant on most film cameras, some digital cameras have shutter lag times on the order of hundreds of milliseconds, which may be a minor annoyance to the user.

Projector shutters

In movie projection, the shutter admits light from the lamphouse to illuminate the film across to the projection screen. To avoid flicker, a double-bladed rotary disc shutter admits light two times per frame of film. There are also some models which are triple-bladed, and thus admit light three times per frame

Shutters are also used simply to regulate pulses of light, with no film being used, as in a signal lamp.

From wikipedia.

DSLR?

The term digital SLR is short for digital single lens reflex, so named because these types of cameras use a mirror positioned behind the camera lens to direct light toward the viewfinder when you're composing a photo. When you release the shutter, the mirror swings quickly out of the way, letting light from the lens travel straight to the sensor and momentarily blacking out the viewfinder. The viewfinder in an SLR incorporates a prism--usually a pentaprism--that flips the incoming image around so that you can see it right side up and bounces it onto the focusing screen where you see it.

The SLR design allows one camera to accommodate a very wide range of lens focal lengths, and that's the biggest reason that SLRs dominate serious photography. The explanation? With a non-SLR camera, you have to match the angle of view of the "taking" lens with that of the "viewing" lens. That's easy with a fixed lens or a short-range zoom, but it requires increasingly complex and expensive viewfinder mechanisms as you try to cover a wider range of focal lengths. With an SLR, you avoid this problem because the taking and viewing lens are one and the same.

Some newer dSLR models incorporate a Live View mode, which allows the photographer to use the LCD to compose shots the same way you can with a snapshot camera. These modes generally lock up the mirror, with the prism diverting the image to a small sensor that feeds through to the LCD rather than to the capture sensor. This does tend to hurt performance, however, and you usually must focus manually when in Live View mode.


Hope I imparted my knowledge to you my readers. :)

Macro 2

From my nikkor 18-135mm lens hood

This insect is about half an inch in size

I got a headache taking this shot! The spider was camouflaged
by the wall and keeps on moving! BTW this is a jumping spider!

Random shots

Sniper shot with my 55-200mm VR. Taken during a
children's party that my daughter attended.

Lansones
From Tiendesitas Pasig city.

First macro trial

I used the reverse lens technique. I used my 18-55 mm kit lens.

Original size is about an inch in diameter.

I took the class!

I got frustrated in reading and learning photography skills through the internet and decided to enroll in a workshop! I registered in sir Nathaniel Salang's workshop in UP (University of the Philippines). And boy I learned a lot! I will be sharing a few things (to be fair with sir Nathaniel) to my readers. This is our class.

I'm the one wearing a blue polo shirt. Lower left. Sir Nathaniel is the
one with cross eyes (Jokingly) far right.

Trial in B & W

My Mom

My wife

Fountain

La Mesa Eco park photo shoot EB w/ fellow pinoy photographers

You can visit the whole preview of the park here: http://www.lamesaecopark.com/

Flowers Galore

"Lonely flower"

"Lonely soldier"

"Caution!"

Lunch break with fellow Pinoy Photographers

Hey kid! Wanna exchange camera?

Saw these koreans taking photos. Took picture of them,
one of them saw and fired back! I guess rules of
engagement exist in photography also!
"Don't fire unless fired upon!" hehehehehe!

Karl bending to shoot good macros!

My other hobby

Slalom racing is my other hobby. It also started when I tried the sport and got addicted to it specially when I was winning in my class category (Front wheel injected class). Here were some photos last December 8, 2007 held in a parking lot in Robinson's mall Fairview.

Me lining up to race. My 93 mitsubishi lancer with its stock engine. :)

Douglas Maningding in his souped up Toyota starlet.
Equipped with a 4AGE hi-horse engine. This Boy started
his slalom career when he was just 8 years old. Now he is 12 years old and still winning.
He is the reigning over-all novice prototype champion. Heck he beats
my time!

The Over-all champion and Slalom king, Noel Rivera.

My team mates. Team MMPH (MYMITSU).
We race with our mitsus. My car is the blue one in the middle
of the photo.

My team mate JR who drives a Mitsu Lancer with a 4G67 engine 1800 cc.
Cleanshine master is his company which manufactures cleaning
products. JR is the one who makes the products (Chemist/Racer/loverboy) hehehehe


An MX-5 Mazda Miata lining up

Joema Montanier with his Frankenstein Toyota Corona
with Nissan SR20 engine under the hood!

B-16 power!

Another Starlet racer

Toyota corolla with a 3SGTE engine. Wapppiissshhh!
Turbo power! Nothing beats the sound of a turbo and a Blow-off valve!

Old school power!