Things To Know About Autofocus

The Auto Focus (AF) System in a camera found in the 1980′s is an important discovery in the world of photography and has had a major impact in bringing convenience to photographers. Without the Auto Focus, we would have to manually adjust the focus on the lens to really precisely focus on the objects we want to photograph (commonly referred to as manual focus). Now that the Auto Focus feature isn’t anything special anymore (except on cellphone cameras), do you really know the ins and outs of this most important feature? Check out the rest of this post to learn more about the Auto Focus.


Auto Focus vs. Manual Focus
AF, or Auto Focus is an automatic process of the camera that aims to find the correct focus. The opposite of which is the MF, or Manual Focus, where the photographer sets the focus manually. MF can be executed by rotating the focus ring on the lens (on DSLRs) or by pressing the designated button (on non-DSLRs). This manual process is generally used when AF fails to deliver results according to our objectives, or if AF isn’t possible due to technical problems.


AF by half-pressing the shutter button
Generally, all cameras will start looking for the focus when the shutter button is pressed half way. The camera will then beep when the focus is locked and the locked object is sharply focused. So avoid pressing the shutter button without first half-pressing, because this will force the camera to shoot without finding the correct focus.


About AF motors
The focus (or lack there of) of a resulting photograph is set by focal lens element that can move back and forth. If using the a AF mode, the camera will automatically rotate the AF lens by relying on the lens’ micro motor. That is why when the camera is focusing, you can hear (and feel) fine movements in the camera. On DSLRs, the AF motor is located inside the camera body, except entry level Nikon DSLRs like the D40 do not have an AF motor. As a substitute, this model needs lenses with AF motors.

Nikon D7000 AF coupling

I SHOOT RAW..! How Important Is That?

Are RAW Files Important in Digital Photography

Many modern cameras feature the RAW file format. This feature may be one of the pivotal reasons why you’ve bought that specific camera, or you may be one of those who never use this feature. For professionals, photographing using RAW is a must. But for beginners, is this feature really that important? The short answer is yes. Find out the “why?” in this post.


RAW file format is the original file produced by the camera’s sensor that hasn’t been digitally processed by the camera. In short, these RAW files are literally the raw files that are substantially larger in file size and are not yet ready for consumption, unlike its JPEG counterpart. Not all cameras have this RAW file feature. Generally, they only provide the JPEGs. Because RAW files are produced directly from the sensors, every camera with different sensor technologies has RAW files that are different. Unfortunately, these different RAW files aren’t compatible with each other and processing them needs supporting RAW processing software for that specific type of camera.


RAW files contain brightness information captured by each pixel (in 12 or 14 bits) and has passed through the color filter (RGB). These files are usually sized at 10s of MBs and uses different names according to their producers. Nikon DSLRs uses NEF and Canons use CR2 as their file names. Having RAW files are like having the negative films from the camera and the post-process done in the computer is like the post-processing done in a dark room.


RAW files are original files that haven’t gone through the internal camera process of:

Take Perfect Lightning Pictures

 

Photographing a lightning is a dangerous hobby. What most people do not understand, is that lightnings are unpredictable and they could strike down any time, anywhere. At the same time, taking a picture of a lightning storm can be very rewarding, especially if the lightning pattern is unique or the picture is taken at an extraordinary location.


1. Use a Steady Surface
While a tripod typically works best, in reality any steady surface will work. Some people use a beanbag or other malleable item, like a pillow.


2.Prepare Your Gear
If you want a very good picture of lightning, a DSLR with a tripod is almost a must. If you have a point and shoot, make sure that the camera can be configured for manual control of shutter speed and aperture. Some people are lucky to have a good image of a thunderbolt in hand, but I strongly advice to use a tripod instead. Depending on the amount of ambient light, you have to use a shutter speed between 30 to 30 seconds and shake any potential negative impact on image sharpness. Either lens would work, but wide angle and zoom lenses work best because you can put more while having the flexibility to change the focal length and target a specific area. A remote cable release or an infrared remote (depending on your camera) is strongly recommended if you want to avoid camera shake, even on a tripod. If the lightning is far away, having a flashlight with you might be useful, since you can “paint” your foreground subject to make the whole scene look more dramatic.


3.Slow Shutter Speeds

ISO Tips. How to use it

If like me you used to shoot with film you might remember 200, 400, 800 etc film speeds. A film with a higher number was known as a ‘fast’ film and many people thought it was for photographing fast moving objects. This is partially correct.

It actually means how fast the film itself reacts to light. A higher number meant you needed less light to record an image. If it was a dull day and you were photographing a motor race you’d need a fast shutter speed to freeze the motion, so you’d choose a high ISO film so you could have the shutter speeds you need in the light that was available. If on the other hand it was a very bright sunny day you could use the lower ISO film because you already had enough available light to get a fast enough shutter speed.

It’s exactly the same with your digital camera. High ISO means you don’t need so much light hitting the sensor to record an image, which means you can use smaller apertures or faster shutter speeds.

Question: Why bother with low ISOs at all?

As with all things photographic there are costs and payoffs. The cost of higher sensitivity comes at the price of grainier photos. The higher your ISO the more grain you’ll get. So for best image quality a low ISO is best, but if there’s not much available light you may have to increase the ISO so you can use the shutter speed and aperture combination you need to capture the image you want.



Let’s take a closer look at a couple of images.

As you can see it’s a bit grainy but it’s still a great image because of the light and her ‘rapt’ expression. But as you can see from the image below, you couldn’t enlarge or crop into it very much before that grain starts to become a quality issue.

10 Tips for Christmas Photography

Photo by David Clapp - www.davidclapp.co.uk

Be ready

If you're heading off to someone else's house for Christmas dinner make sure you put your gear in your camera bag and pack it or at least leave it somewhere it won't be forgotten the night before. Things get a bit hectic on Christmas day and with all the running around, organising kids and packing presents in the car it's easy to forget your camera!

Make sure your battery is charged and pack a spare. Don't forget extra memory cards too, just in case.

Lighting

If you have patio doors or large windows, make use of the natural light and shoot your Christmas portraits near them. However, if you're up early when it's still dark or are still shooting late into the evening there won't be enough light around for you to use quick shutter speeds. This is fine if you're shooting a subject that doesn't move but for people shots or close-ups (snow-covered plants / flowers) where you need to use a small aperture so you have greater depth of field, a slow shutter speed would give you a blurry shot as your subject can't hold still for long enough. As most cameras, such as the Samsung NX200, now handle noise well at higher ISO levels you can increase your ISO to give you the quicker shutter speeds you need. However, most of the time when you're shooting indoors you'll probably need to use flash. The problem with your camera's built-in flash is it can end up making your subject look like a deer caught in someone's headlights with a rather harsh shadow behind them. You can try and diffuse it or better still, use an external flash gun that you can adjust the position off. You can also bounce its light off a nearby wall or the ceiling rather than firing it directly at your subject.

White balance

Do take a couple of test shots, both when you're working indoors and out, as you may need to switch from auto white balance to one of the other pre sets available or to manual. You can always shoot in RAW and make your adjustments later during post production but it's always best to try and get it right in-camera while shooting. If it's snowed and you're outdoors make sure the snow doesn't end up looking more blue than white.

Artificial Snowfall In your Photos | Photoshop

First, you need to pick a photo that will look natural once you add the snow to the shot. This tutorial works best with a shot that has a small covering of snow on the ground. Once you have a shot chosen, open it up in Photoshop.

Photo by Daniel Bell.

Create a new layer

To create our snow we need to make a new layer so go to Layer>New Layer or click the new layer icon in the layers palette. Rename this layer to 'Snow'.

Make a selection

Select the Rectangular Marquee tool and draw out a shape that's a 1/4 to 1/2 the size of the main image, making sure you have your new layer selected. You should now have a shape that's outlined with 'running ants' over your shot.

Want to buy a Polarising Filter? Here's the guide

You may be aware that a polarising filter is one of the most useful additions to your camera kit, but there are a few things you need to decide before buying one.

Linear or Circular?
First thing you should know is that there are two varieties - linear and circular. Although they're both physically round, a linear variety can have an effect on the autofocus or metering accuracy of any camera that uses a semi-silvered mirror or prism to split the light entering the viewfinder. This is known as a beam splitter and is used by most modern SLRs to calculate exposure and focusing distance.

As a rule use a circular filter if you have an autofocus camera or a manual focus model with a spot meter such as the Canon T90 or any modern digital SLRs.

Screw-in or System filters?
Next thing to decide is whether to buy a round, screw mount filter or a system version that slots into a filter holder. Round ones are often easier to adjust and feel better built. They're also more compact to carry around. The disadvantage is larger sizes are more expensive and, if you have two lenses with different filter thread sizes, you may need to buy two filters, whereas a system type would just need another adaptor ring for the filter holder.

The filter holder type can also cause vignetting when used on some larger thread wide-angle lenses. Equally, a larger filter holder may prevent vignetting when used on a smaller thread wide-angle.
Features to look for

• If you have a camera without through-the-lens viewing look for a filter that has an index mark printed on it. This will help you align the filter correctly.
• Some filters have a small screw-in arm to help rotate the filter, which is useful if you intend using the filter when wearing gloves in cold weather.
• Filters with thick rims can cause slight vignetting when used on wide-angles. The latest Pro1 D versions from Hoya have slim rings.
• Check whether the filter is circular or linear. It will often say PL CIR if it's circular, while linear often just has polariser or PL marked on the rim.
• Polarising filters for square system holders are still round so they should rotate easily in the holder.

Who makes them?

Choose The Best DSLR Lens - 6 Topics

If you think that finding a good SLR camera is tough, try to find the best digital SLR lens to go with it. If you felt there were plenty of cameras to choose from, the number of available lenses is going to be overwhelming. Digital SLR lenses come in all manner of shapes and sizes, and vary massively in price.By simply changing a lens, the scope of a potential image changes, too. Understanding the difference between lenses will help you get the best shot. Some are built for the demanding needs of professionals and others are just right for the everyday snapshot photographer. Faced with all these alternatives, what’s a newcomer to the world of SLR photography to do?

Just follow the 6 steps that I outline below and you’ll find your way to the best digital SLR lens for your camera.

1. Find Your Focal Length
Before I get too far into my discussion of focal length, I’d like to provide you with a definition of the term. Focal length is measured in millimeters (mm) and it represents the distance from the optical center of a lens to the digital camera sensor when the subject of the photo is in focus. That’s the textbook definition, but it really doesn’t explain too much about why focal length is useful.


Here’s the plain-English translation:
* With a short focal length you have to be close to your subject for a close-up
* With a long focal length you can be far away and still get a close-up
* A zoom lens has a variable focal length
* A prime lens has a fixed focal length.
How do you decide which focal length lens you need? It all comes down to what you want to photograph.


2. Prime and Zoom Lenses
Step two on your path toward finding the best DSLR lens requires a decision between prime and zoom lenses. Since you’ve already made up your mind about what focal length you’d like, choosing between prime and zoom is further narrowing the field of digital SLR lens options. Each lens type has advantages. The decisions that you make about which kind to get will depend a lot on what sorts of pictures you want to take with the lens: clearly, a gigantic heavy zoom lens is not going to be your best option if you’d like to travel with your camera.

The Correct White Balance

I find the 'auto-white-balance' (AWB) of the Canon X0D, XX0D series cameras to be on the 'cool' side. Images are simply 'cooler' than what was 'before my eyes' when I took the picture. This is easily remedied by setting white balance to match your shooting conditions.

• If it's sunny out, set white balance to 'sunny'
• If it's cloudy out, set white balance to 'cloudy'
• If it's shady out, set white balance to 'shady'

It seems obvious, but most folks leave white balance set to 'auto white balance' (AWB).

If you want to 'warm-up' your images further, try the following:

• If it's sunny, set white balance to 'cloudy.'
• If it's cloudy, set white balance to 'shady.'

If you've been shootng outdoors using AWB, I think you'll be pleasantly pleased by this little tip.

If you shoot in RAW format, you can experiment with different white balance settings when you process the RAW file. You also have the ability to interactively adjust white balance based on color temperture -- this gives you even more fine-grain control over white balance.

I took the following photo (shot in RAW) and processed it using 3 different white balances (auto (AWB), cloudy and shady):

Auto White Balance (AWB) [the default] - too 'cool' for my taste.

5 Habits To Stay Away From

For as long as I’ve become a photographer, there’s a list of bad habits that’s as long. These bad habits of photographers could be easily avoided if you’re willing to start as early as possible to avoid further losses.


These bad habits in Photography usually include:


1. Not checking the completeness of the equipment.
True, usually photography equipment are stored in a singular bag. But it never hurts to recheck the contents for a shoot the next day. The item most often left behind is the memory card. Usually, the photographer transfers photos from the memory card to a computer and forgets to return it. This also happens when recharging camera batteries. So, it’s best to always double check before embarking on a photo shoot.


2. Not double-checking the camera settings.
Not double-checking the camera settings before a photo session can be fatal. Imagine, during a photo shoot, you forgot to double-check your camera settings, and it turns out that the camera was set at the lowest image quality setting, very high ISO, and unsuitable WB settings. Unbeknownst to you, these settings are used all throughout the photo shoot and you only notice it when photos are transferred to a computer. This will certainly be detrimental to the results.


3. Overly dependent on Photoshop.
I’m not anti Photosop. The existence of this incredible software has helped me throughout my career. But we must restrain ourselves and not let the advancement of software technology hinder us from always wanting to achieve a good photograph. The term “it can always be photoshopped later,” can be a dangerous mantra. This creates a lazy mindset and lessens our on-site photographing quality. A thorough photo shoot will certainly save time and effort when in the editing session. And let’s face it; you’ll be proud of yourself for creating a beautiful photograph and not just a beautifully edited photograph.