SLR Cameras - What Is A Single Lens Reflex?

The hottest thing in the digital camera market is undoubtedly the digital SLR, which is better known as a dSLR. While dSLRs are flying off dealer shelves, many new users are confused about the terminology. Most people know that SLR stands for "single lens reflex." Since nearly all SLRs accept interchangeable lenses, it would appear they should be known as multiple lens reflex (MLR) cameras.

If you want to understand how the SLR received it's name, you have to dip into the history of the camera. Early cameras were similar to the view cameras used today. The photographer looked through the lens, focused, composed and then inserted a single film plate behind the optics to make an image. While the entire process was crude by modern standards, the photographer enjoyed great control, since he looked directly through the actual imaging lens to compose the shot.

While this was fine for still life, portraits and landscapes, this process did not lend itself to action photography. These early cameras could only record a single image at a time. Which is why you have never seen a motor-driven view camera.

Realizing the need to offer sequences of exposures, camera makers begin to experiment with various roll-film designs. With a roll of film in the camera, the photographer could fire off numerous images without reloading. Although this improved throughput dramatically, it caused another problem. The roll of film had to pass closely behind the camera's optics, which meant that the photographer could no longer look through the camera lens to compose and focus.

Rangefinder cameras appear to keep things in focus

The lower-end, consumer roll-film cameras generally used an inexpensive "fixed-focus" lens, so a simple viewfinder was sufficient. Better quality optics, however, require the lens to be focused, and since the photographer could not look through the lens with a roll-film camera, this was a major problem. One of the first solutions to this problem was the Rangefinder -- a type of camera that offered a distance measuring scale in the viewfinder. By determining the range from the viewfinder, the photographer could then adjust the focus to match -- usually with very good results.

Twin Lens Reflex cameras offer another solution

While the rangefinder type cameras worked well, the camera industry is always evolving. A second method of allowing the photographer to focus and compose appeared in the "Twin-Lens Reflex" cameras. These cameras used two identical lenses, arranged one on top of the other in the manner of an over-and-under shotgun. The film winds past the lower lens, while the photographer can focus through the upper lens. The twin-lens cameras were fairly bulky, so designers added a mirror and ground glass to the top of the camera, hence the term "reflex.

Now the user could hold the camera at waist level and look down at the ground glass which previewed the image via the mirror behind the upper lens. As the user adjusted the focus on the upper lens, a gear mechanism moved the lower "taking lens" to match.

While both rangefinders and twin-lens reflex cameras offered a credible way to focus and preview a shot, neither allowed the photographer to actually look through the lens. This sometimes made exact composition difficult.

SLRs take cameras another step forward

In their quest to allow users to see through the actual "taking" lens, camera makers turned to the periscope -- a simple device using two mirrors placed at opposite angles to bend the light path. Periscopes are easy to understand -- any kid can construct one from a couple of mirrors and some scrap wood.

In a camera, the lower mirror is placed at a 45 degree angle directly behind the lens. Light striking the mirror is projected upwards to a ground glass. While a second mirror would show the image on the ground glass to the user, it would not appear right, because mirrors tend to reverse things. So camera designers added a prism arrangement that corrects the reversed image. When you peer through the viewfinder on a SLR, you look through a prism, which displays the image on a ground glass, which displays the projected image from the mirror located behind the lens.

There is just one problem. If you have been paying attention, you have no-doubt realized that the lower mirror blocks the light path to the film (or digital sensor as the case may be.) Now the photographer can look though the lens, but the image cannot be projected on to the filmplane.

So the camera designers had to add another wrinkle. They had to move that mirror. Just long enough to make an exposure, since when the mirror moved, the photographer could no longer see anything through the lens. So they designed the "instant-return" mirror. At the instant of exposure, the mirror flies upward, the shutter fires and the mirror snaps back down. It is a incredible feat, when you consider that instant return mirrors have to flip up and back in a heartbeat, over and over for the life of the camera.

Once the instant return mirror was perfected, photographers could once again design their images by looking through the lens. Unlike the twin lens reflex, this new breed of camera needed only one lens to focus and shoot with. So they became known as... you guessed it.... Single-Lens Reflex cameras.

Visit http://alphatracks.com where you can find a large selection of free photography articles. You can also subscribe to the Alphatracks RSS feed.

Tom Bonner provides photography and web design services to clients in the Gastonia, North Carolina area. You can find out more about Tom at http://adventuresindesign.com

Low Light Digital Photography

Achieving good quality photos in low light can be accomplished in a number of ways. The traditional methods for handling low light situations still apply, such as increasing aperture, reducing shutter speed, using higher ISO or use of a flash. However with digital photography there are additional considerations.

Increasing aperture (lower F-numbers) opens the lens' internal blades that restrict light from entering the camera. By letting more light in, you can obtain the proper exposure while keeping other camera settings the same. The two issues to consider when using a reduced f-number, is the reduction of depth of field and that most lenses do not perform as well at their widest apertures.

Lowering shutter speed without making other adjustments can also help in getting the desired exposure. The rule of thumb is to set shutter time to no less than the focal length of your lens. So if you are using a 50mm lens, you should generally try to keep the shutter speed above 1/50 of a second. This will help prevent motion blur of the image due to camera shake.

Camera shake and the blurring of images is always a problem when using long shutter times. With telephoto lenses this issue is even more of a problem. Wildlife photographers, sport shooters and reporters often struggle with creating good images in less than ideal lighting. Even taking pictures of moving people (e.g. children) indoors can often result in motion blur.

Fortunately modern image stabilization (IS) systems are now available from all major camera manufactures. Currently there are two methods for implementing image stabilization. The first is a system built into the camera body (Sony, Pentax and Olympus) which actually moves the sensor to counter camera movement. The second type is an in-lens system (Canon and Nikon) that moves internal parts of the lens to reduce blurring of images. Which system is better is a debate that will probably never reach a conclusion. In either case IS can significantly reduce problems due to camera shake during shooting.

Increasing ISO increases the camera sensor's sensitivity to light. So a higher ISO will allow you to use higher shutter speeds or smaller apertures in the same lighting conditions. These changes can be helpful for achieving the image you desire by controlling depth of field and reducing motion blur.

In the days of film increasing ISO was done by using high ISO film. In the digital era all you need to do is locate the ISO adjustment on the camera. However, just as high ISO film had problems with grain, digital high ISO settings come at the expense of digital noise.

Thankfully recent advances in camera sensors, especially with digital SLR types, allow for very high ISO setting with relatively low noise. Improvements in noise reduction software have also made extremely high ISO photography possible. Recent advanced amateur level cameras from Nikon and Sony allow for ISO setting of up to 6400 and one of the professional Nikon dSLR is usable up to ISO 25600 which was never possible with film.

Advances in dSLRs have made flashless low light shooting much easier than it once was. High ISO performance and image stabilization systems are rapidly developing. Many cameras that are available today are very good but you need to do your homework before you buy. If you are not yet invested in one system's lenses you have a lot of excellent options, but don't sell yourself short by picking up an out of date camera body unless you know what you are giving up.

To learn more about cameras, try The Camera Spider.

Have you considered a single use digital camera to spark your photographic creativity?

Why Reading Books on Photography Can Greatly Improve Your Skills

Photography, and the camera itself, have come a long way since their humble beginnings in the early 1800's. Compare the old pinhole camera to today's modern DSLR models, and they are worlds apart. Compare the photographer of yesterday to today's and they too are worlds apart. Today's photographer needs a whole new skill set to produce frame worthy prints. There are many ways to improve your photography skills, whether you are an amateur or a professional, but one of the best ways is by reading books on photography.

While most newer model cameras come complete with both a manual and a digital menu built in, if you want to improve your photography skills, and take your photographs to the next level, books are the way to go. There is a vast array of photography books available on the market, all designed to improve your skills as a photographer, as well as challenge you.

Reading books on photography can take you places you didn't even know you could go with your camera. While there is something to be said for experimentation, there is even more to be said for skill. Reading books and having the resource on hand while you hone your talent is invaluable. By reading up on how best to use your camera, how to utilize lighting, shutter speed, or change the aperture can take your photographs from average to amazing and greatly improve your photography skills.

Photography books can both inspire and teach you to take the kinds of photos you've always envied. By reading tips on photography and seeing first hand examples of what can be achieved simply by making the correct adjustments on your camera, or with the composition of a photograph, you can begin to get the most out of your camera. Having a book on hand enables you to learn at your own speed, and on your own time. Books are portable and can be taken with you on your photo shoot, whether it be to a park, a family gathering, or a nature outing. Having a handy resource can be the key to getting the perfect shot.

A camera is a big investment, and like with any investment, you want to get the biggest return you can. Improve your photography skills, and be the kind of photographer you want to be. Choose a topic, set a goal for yourself, and explore the world of photography books.

And finally, if you are interested in the  best photography books  to improve your skills, please check out Best Photography Books HQ at  http://www.bestphotographybookshq.com.

Facts About Modern Photography - Learn More Here

Once the birth of the camera arrived and the popularity of photography exploded, the only thing that could follow was mass production of cameras as well as the wide distribution of pictures. As a result of photography, it has changed history, art, memories and the in which we view the world.

This also affected well known public figures and this caused their privacy to vanish. They were constantly being photographed. Having a photograph with clear evidence that a certain event has taken place would cause things to go unchallenged.

The Art Form-

It was not accepted in the early years. The art form was criticized and challenged by many of those that opposed it being considered an art form. Photography was considered a hobby or craft and was looked at as an insult when one considered it an art.

Photography is finally accepted-

Once art schools and galleries as well as museums finally started to come around and embrace it as an art, the impact grew wildly and the end result is what we have today in the world of photography.

During the mid 1960's photography was accepted as a visual art and photographers started creating mediums of interest that were different from the more traditional norms that were first used within the art form.

Photography has been combined with other forms of expression such as multi-media and other forms of imaging.

Practical Photography-

Photography has been used for many practical situations. Photography is often time used in medicine, real estate development, military planning as well as business and media.

One area that has benefited from photography the most is science. If you think in terms of aerial maps, meteorology and geology, you'll notice they all use photography to advance the research and fact finding process.

Digital Photography-

With the invention of digital photography and the use of software, images can be changed and appear to be more or less than what they are.

As a result of digital photography being created, this caused a change in the way in which many photography techniques are used.

Photography is more than 100 years old and this is one art form continues to innovate and create new and improved technology and methods. You'd think we were on the tail end of the art form but the art continues to grow and develop and it does not appear to being slowing down anytime soon.

If you'd like to keep up with the latest developments in photography, I'd suggest you subscribe to a few of the leading magazines as well as follow a few of the cutting edge blogs.

About The Author

Keith S. Black has many different photography methods. He is a successful photographer and makes a full time living as a photographer. To find out about one of the best cameras to use for your photography you can visit: http://reviewdslrcameras.com/nikon-reviews/ to read one of Keith's Nikon Reviews and get more information.

Digital Photography for All Shooters

Digital photography has drastically changed the way people make and view art. To die-hard hobbyists, the craft is no more than mediocrity glorified. To the ordinary man of the streets, the pursuit is one of the boons of modern technology. This article will not focus on the debate between traditional art and digital art, but will rather show you how digital photography can cater to the varied needs of the users.

There are several opinions that surface with the mere mention of the phrase "digital photography." The most common and yet most ironic are: That digital photography is a matter of pointing and shooting pictures and that digital photography is not as easy as you think! Both statements are true - depending on the kind of camera you use.

Point and Shoot Digital Photography. This type of digital photography uses the popular budget cameras. Most moms, students and travelers you meet would say they prefer to point and shoot.

After all, what's not there to like? The camera is pocket-friendly size-wise and money-wise. For as little as 100 dollars, you can take beautiful photos conveniently with little or no adjustments to the settings. You can even skip reading the manual and have a quick go at the device.
Pointing and shooting pictures is a great way to start your romance with digital photography. It offers you that icing-on-the-cake charm that might just prompt you to become a serious photo hobbyist some day.

Digital Single Lens Reflex (DSLR) Photography. This type of digital photography uses the pricier merchandise starting at 400 dollars and up. Many of the shooters have outgrown the allure of point-and-shoot convenience.

DSLR photography still has the automatic settings of point-and-shoot cameras. What makes it a challenge is that it gives you more features to play with. The rewards are of course every serious photographer's joy: various manual controls to let you tweak your work, better quality images, more creative control of your shots, and greater overall versatility.
You must have fallen deeply in love with the craft to pursue DSLR photography. Since the gadget is intended originally for an array of manually controlled settings, there's a steep and complex learning curve ahead of you that's waiting to be explored.

Do you wish to take photos without the fuss? Or are you in the mood for a more challenging and more rewarding photo shoot? Either way, you're sure to find your sweet spot in the world of digital photography.

Sally Stoneking is a work at home photo enthusiast who discovered the best way to sell photo prints online. She was so inspired with this method that she wrote a book that teaches others how to sell images online. Check out her website, Nature and Flower Pictures where you will find great prices on affordable stock photos.

Digital Cameras - Should You Go With One?

If you considering buying a camera, the first question you will face is whether to go digital or not. Cameras have undergone a massive evolution over the last ten years and digital is now really the most popular platform in the field.

Why go digital? Well, the modern digital camera is an exercise is convenience and quality. These cameras are point and shoot affairs. This would usually mean they are easy to use, but produce pictures that look like...well, not so hot when it comes to their clarity and sharpness. This isn't the case with most digital cameras. The quality of the photographs is top notch and, if it isn't, there are ways to fix it which leads us to our next point.

The huge advantage to digital cameras is...they are digital! This means no developing and printing. You can simply use memory cards or usb cords to download the images to a computer. You can then use software to edit out blemishes and then just post them online if you like for family and friends to see at their leisure. To get a taste of how popular doing this is, just take a gander of Flickr.

Ah, but what if you prefer traditional photography. You enjoy the framing of the picture or want to shoot unique exposure rates and the like? Well, no worries. The DSLR camera is you choice. This product is a single lens camera like you are used to losing, but with a digital image capture system. I personally prefer these cameras. You get the unique, personal touch of taking the picture, but the easy of a traditional camera in that you can just download the images to your computer. If you love photography, you'll fall in love with DSLR cameras pretty quick.

Should you go with a digital option when making your next camera purchase? I would recommend it.

Thomas Ajava writes about cheap digital underwater cameras [http://www.digitalcamerashowdotheywork.com/digital-camera/cheap-digital-underwater-cameras] and other subjects related to photography and digital cameras for DigitalCamerasHowDoTheyWork.com [http://www.digitalcamerashowdotheywork.com].

EVIL Cameras - A Formidable Foe To The Modern Day DSLRs

Some of you may have already heard about them. For those who haven't, these systems are a new breed of cameras that share similar functionalities to DSLR cameras but are much smaller in physical size. There is a possibility that it may even have more features than the DLSR you currently own. Now that's truly EVIL. One such system is the Sony NEX 5.

EVIL stands for Electronic Viewfinder Interchangeable Lens. Unlike the DSLR camera it doesn't have a through the lens optical viewfinder which is probably one of the main reasons why DSLR cameras are so big. Like DSLR cameras, you have the ability to change lenses.

So what's the big deal about these cameras? Aren't DSLR cameras the way to go?

To answer these questions, lets look at some of its pros and cons.

- Depending on the brand and model, the sensor size may be similar to the DSLR counter parts. This is the case for the Sony NEX 3 and NEX 5. Both these systems use an Advanced Photo System type-C (APS-C) sensor, which are the same as what you will find in the entry level DSLR cameras in the Sony Alpha line. Compared to the sensors in your PnS camera, these sensors are about 9 times larger! This means you can take better pictures in lower lighted environments in comparison to the PnS cameras.

- As the systems are smaller, these systems are extremely portable (fits nicely into your hand bag) and light. This also means that the camera body is too small to place the same number of hard buttons as DSLR cameras. You may have to navigate in a menu to access certain functionalities.

- At this point in time, optical view finders are still preferred by professionals as its easier to see your subject in poorly lighted environments. However, technology may improve in the near future. Who knows, we may have night vision features like what's offered in some Handy cams one day.

- As EVIL cameras are relatively new in the market, they offer some of the latest features that digital cameras can offer. The Sony NEX 3 and NEX 5 have the ability to take HD videos, Sweep Panorama shots, 3D shots, auto HDR and more. None of these features are available with the DSLR camera that I own and use.

- As these systems are quite advanced, they cost as much as entry level DSLR cameras. Sometimes a little more than the cheapest DSLR cameras in the market.

So how do I decide on which type of camera is best for me?

You should get a PnS camera if

- You are on a tight budget.

- High quality pictures and low light capability are not important.

- You want a small digital camera that performs better than your mobile phone.

You should get an EVIL camera if

- You have a higher budget.

- Quality pictures and low light capability is important to you.

- You want your system to be small enough to fit into your handbag or maybe even into your pocket.

- You want the ability to change lens.

- Your main objective for using a digital camera are for casual shoots only e.g. group shots with your friends, travel pictures when you go for a business trip etc.

You should get a DSLR camera if

- You are a serious about photography and wish to explore all it has to offer (e.g. usage of a wide range of accessories to get interesting results).

- the genres of photography that you are interested in require to be able to change your camera settings quickly e.g. weddings.

- You intend to do photography professionally.

There are sensors that are bigger than the APS-C sensor, which offers other benefits. However, these systems are preferred by a totally different group of people with different requirements. I hope what I have written so far would give you a good idea about EVIL cameras and how you might prefer getting one to a DSLR camera. Cheers!

Darren Francis is an Award Winning Photographer from Singapore. He provides a wide range of photography services including wedding photography and is an experienced photography trainer as well.

If you would like to view more of his works and photography tips, kindly visit his website: http://www.darrenf.com.