Why is there a mirror inside an SLR?

All SLR cameras use a mirror and a penta prism model to reflect light through the camera body and the photographer can see the scene through the view finder. The below video demonstrates the light path through a SLR camera.

How SLR camera work

Since the light reflects of the mirror it gets the term Reflex. Combining the definitions based on how light enters and reflects its called a Single Lens Reflex or simply SLR.

How can I become a photographer?

This is a typical question asked by any one aspiring to be a photographer. However there is no shortcut or straight forward answer to this. It requires lot of passion and dedicated study of art and science. This will also require to identify the subject that interests one a lot. There are many professional courses that are concentrated on grooming aspiring professionals in to professional photographers by giving sufficient knowledge on the subject and also on other varied subjects required to be a successful photographer. As a colloquial saying goes “A mediocre photographer with strong business skills outperforms a great photographer with mediocre business skills”.

The below video depicts a typical path any photographer undergoes during the course of the time.

What is a DSLR and is it different from SLR or Film SLR?

 SLR and DSLR are very similar or we can even say same in functionality. The only major difference between them is the medium on which the light is captured. The film SLR uses films as the light sensitive medium and the digital SLRs or DSLRs have digital sensors to capture the light. Other differences include the massive menu systems and the screen provided to review the images on a DSLR. Film SLRS have very simple menu systems and mostly mechanical controls using knobs and dials. After digital revolution came to being lots of functions are being controlled using menu systems and some of them very typical to the digital photography which were not required for film camera.  But both these cameras work using the same philosophy.

What is an SLR ?

SLR stands for Single Lens Reflex. As the name suggests it has only one (single) lens attached to the body of the camera. An SLR camera can be broadly considered to have two major components. The lens and camera body. The Lens can be attached or removed from the camera body. Since there is only one lens attached to the body of the camera the term Single lens is used. All SLR cameras use a mirror and a pentaprism model to reflect light through the camera body and the photographer can see the scene through the view finder. The below video demonstrates the light path through a SLR camera.

Since the light reflects of the mirror it gets the term Reflex. Combining the definitions based on how light enters and reflects its called a Single Lens Reflex or simply SLR.

Are there any short cuts to become a photographer?

As with any other discipline for photography also there is no short cut in this world for success. Short cuts may be there but it will not weather the test of time. So it’s time to make the fundamentals right and climb the ladder slowly to achieve your artistic goal. The below video give a birds eye view of how to lay the foundation to photography and how to build on the foundation. Good luck.

The photographer's foundation of knowledge can be represented in the form of a pyramid. The pyramid is very strong at its base. The very reason why it could be built very tall.

Similarly if you want to take your photography to great heights a strong base is required.

The technical details and knowhow forms the base of the pyramid for the photographer's foundation of knowledge. Upon which one can solidly build an artistic platform for self expression.

Please view the video to understand the photographer's foundation of knowledge in a visual form.

A photographer's foundation of knowledge

One would have noticed that the typical terminologies used in photography like, focusing, exposure, ISO, shutter speed, aperture, camera details all come under the technical aspects of photography. And as we move up the pyramid the technical aspects slowly merge with the artistic elements. Any ways technical aspects in photography is an integral part as its the very nature of this medium of artistic expression.

One may have noticed that technical aspects can be learnt and perfected in a few weeks to months time but the artistic process is an evolutionary one. 

18 percent gray card

Most of us are aware of the importance of a Gray card in reflected light metering.

Here is a little story behind it. I use a gray card from Kodak which I bought from BnH here is the link http://bhpho.to/12kAXIg.
However there is a caveat before using it. Please read through.

What is a 18% Gray card?

 Many reference “gray cards” are referred to as 18% gray. In the printing industry, 18% reflectivity is considered halfway between the white of paper and the black of printing inks. However, actual scene luminance is a bit different from the brightness of printing ink on paper. Light meters are calibrated to an ANSI (American National Standards Institute) standard of 12.3% reflectivity, which is a closer match to 50% luminosity or L=50 (in Lab colorspace). For some unknown reason, reference cards in use for  photography, if they are calibrated at all, choose 18% to represent medium gray! This may come from Kodak who continues to manufacture and market an 18% gray card. 18% gray actually refers to a printing specification (Kodak’s cards are produced using printing ink on an offset litho press) and presumably this makes it easier to manufacture. The bottom line is that the 18% Kodak gray card is a bit “lighter” than the 12.3% reflectivity that light meters are calibrated to and so, if you expose at the reading you get off the Kodak card, you will be underexposing by about 1/2 f-stop. Ansel Adams was aware of this and made reference to a mysterious “K” factor in his Camera and Lens book that had you opening up by 1/2 stop from the reading off the card.

I prefer the incident light meter reading or in reflected light meter an exposure precision afforded by adjusting exposure in 1/3 stop increments; therefore, to avoid overexposing, I only open 1/3 stop from readings taken off 18% gray cards.
Try it. You will be amazed to see the results.

I bought from BnH here is the link http://bhpho.to/12kAXIg. 

High Speed Sync: auto fp and cls

Most of the modern DSLRs can work in high speed sync mode. That is the flash works at shutter speed higher than that indicated as the sync speed.

As we all know how the front and rear curtain of the shutter work to achieve those high shutter speed. First curtain travels and before the first curtain covers the entire sensor frame the second frame starts to close leaving just a small slit being exposed at that time. if the flash fires at this time only that part of the frame which was exposed at that point gets the flash light leaving other parts dark.

This is the reason why there is a sync speed for focal plane shutters which is much slower than the the leaf shutters which is built on to the lens unit making every lens even costlier. 

But in modern day cameras there is an option to bypass this sync speed and use flash at much higher speeds. The AUTO-FP option in the Flash menu in Nikon is the one you have to use for this. Canon users can use the High Speed SYNC option on Canon cameras. This is built in to most of the cameras but we need dedicated flashes which can work in this mode. Nikon SB600, Nikon SB700, Nikon SB800, SB900, SB910 support his mode. Built in popup flash do not work in this mode. Its called AUTO-FP in Nikon because it works in high speed sync mode as long as the shutter speed is higher than the sync speed. But when the shutter speed is equal or less than the the sync speed of the camera it automatically switches the flash to normal sync mode giving a single pulse of light

How the flash works is instead of putting out light in one single pulse, the flash actually flickers for longer amount of time throwing out light for longer duration as long as the 2 shutters roll over the sensor completely  This can be used only as a fill in light as the flash looses around 2 stops of light in this mode. This is highly useful for nature photographers or out door photographers when we need high shutters and open aperture to blur background fill in flash in this mode can help to put some fill light and give catch light to bird's eye or the subject's eye. To improve the throw of lights from flash there are custom made Fresnel lens called the Better Beamers from www.lenscoat.com which allows the light to be magnified there by improving the throw and hence covering more distance when using longer telephoto 

lens.

COMPOSITION IN PHOTOGRAPHY

Composition, a word most commonly used by the artists. What a common man knows but cannot comprehend.

What a photographer is taught from the day one. Compose your frame intact before you press the shutter. Use the gridlines in the viewfinder for assistance.

Divide your frame into 3 equal parts horizontally and vertically. Place your subject of importance at the intersection point. That’s where the eye falls at the first glance.

Balance your images on right and left. Keep the horizon at one third or two third of the frame. Do not cut the lines in the middle of the frame. All are implied rules. They rather have to be followed explicitly irrespective of the kind or style of photography being practiced.

Consider a frame as below contained inside a rectangle in the normal aspect ratio of 2:3.

The upper edge of the frame is called the suspension or if we compare it with nature its the sky. The lower edge of the frame is called the support or if we compare it with nature its the earth. 

The two sides form the balance. It can be compared to the regular weight balance. For a balanced frame it should have elements that can balance the frame. Simple is it.

In the below image the scenery is beautiful but the image has to be balanced on the right hand side.  Putting the boatman on the right hand side at the intersection point balances the image and the emphasis is given to the boatman (becomes the important subject in the picture).

The rule of thirds. How this is arrived at is a simple logic. Here is the logic.

Simply give 5 one rupee coin to your maid at home and ask her to divide it into 2 unequal parts. Irrespective of whether she calculates or not the instinct would be 2 and 3.

This is the psychology behind it or the human mental balance. This was just a story to substantiate the below theory of composition.

One of the best books to learn composition in photography.

If you divide 5 = 2+3 you are mentally balanced with the result. But 5= 1+4 though right theoretically but we feel little uncomfortable. Do I make sense here. This holds true for 99% of the population.

Typically the ratios that appeal to us are of the form

1/3 = .333

2/3 =  .666

2/5 = .4

3/5 = .6 and so on but revolves around the above concept.

Similarly we tend to look for these ratios our eyes tend to scan the portions in the photos where these ratios fall approximately. Thus the rule of third.Now let me take you through some mathematics and simple geometry drawings.

BC = ½ AB

BD = AB

C is the center; CD the radius cut the arc.  The ratio is obtained which substantiate for the rule of thirds.  

This explains why our eyes scan the photos at places where our otherwise conscious mind would not look for or simply put the rule of thirds. Place the objects at the meeting points of these lines.

Last but not the least. Rules are meant to be broken. But knowing what you are breaking makes a difference.