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Monday, October 21, 2013

INCREASE MEMORY POWER

A strong memory depends on the health and vitality of your brain. Whether you're a student studying for final exams, a working professional interested in doing all you can to stay mentally sharp, or a senior looking to preserve and enhance your grey matter as you age, there are lots of things you can do to improve your memory and mental performance.
Ways to Increase Memory Power

1. When you exercise the body, you exercise the brain.

2. Improve your memory by taking a good nap.

3. Happy relationships and fun with friends.

4. Laughter is good for your brain.

5. Reduce stress.

6. Feed your brain.

7. Make sure to have sufficient amount of Vitamin B

8. Eat more fruit and vegetables.

9. Reading is a good exercise to your brain.

Foods rich in flavanols such as grapes, apples, blue berries, green tea, broccoli, onions together with dark chocolate happen to be researched and outcomes reveal that individuals who include these types of foods within their diet regime have much better mental functions and skills.

They are some of the health advantages that individuals can gain when they consume flavanol-rich food on a regular basis. They’re also capable of improving mental functions too. Seniors could focus on improving the memory capabilities by including these food types in their diet plan. They could enjoy having dark chocolates however in the proper amounts. Something that is taken in excess might be harmful. Individuals particularly the elderly have to seek advice from the doctors and the expert in nutrition so they may have heard how much of it they could take each day.

Apart from assisting memory enhancement, flavanols also improve metabolic processes by giving adequate supply of antioxidants.

Protect Your Brain:
Antioxidants
As people get older, substances called free radicals, which are floating through the bloodstream, will break down the brain cells. If you don’t put up a fight, you’ll experience loss of memory as you age. However, there are a good deal of antioxidant food sources to choose from. Antioxidants will merge with these free radicals, turning them harmless. Make sure you eat foods that have this healthy food source. Several good sources of antioxidants include:
  • Blueberries (other berries too)
  • Broccoli
  • Carrots
  • Garlic
  • Red grapes
  • Spinach
  • Soy
  • Tea
  • Tomatoes
  • Whole grains

Regulate Your Fuel Supply:
Fiber Foods that contain a good dose of fiber include:
Dried fruits – apricots, dates, prunes, raisins
Vegetables – broccoli, green peas, spinach Peas and beans – black-eyed peas, kidney beans, lima beans
Nuts and seeds – almonds and flaxseed
Whole fruit – avocadoes, kiwi, oranges, pears and skin-on apples
Whole wheat grains – barley, brown rice, etc.
The greatest sources of food to boost your alertness, concentration, and energy are:
*Dairy products
*Eggs
*Seafood
*Soy
Hydrate Your Brain:
Water
You already know that your body is made mostly of water. And you also know how easy it is to not consume much water and become dehydrated. Even a mild case of dehydration can reduce your mental energy and capacity, causing your memory to become impaired. You should drink at least four liters of water each day, or six to eight glasses of water

Thursday, October 3, 2013

SOME TIPS FOR PHOTOGRAPHERS

Whether photography is a hobby or a profession, you'll get a whole lot more out of it if you understand how it works. With a firm grasp of aperture, shutter speed, sensitivity and focal length, the ratio of truly great to merely mediocre shots you download at the end of an expedition is all but guaranteed to climb.

Don't uncap your lens without reading these tips.
Aperture

1. Understand aperture
The most fundamental element any photographer should understand is aperture. The aperture is the physical opening within your lens that allows light through to the sensor (or film in an older camera). The wider the aperture opening, the more light can pass through, and vice versa.

The size of the opening, which is regulated by a series of fins encroaching from the edge of the lens barrel, is measured in so-called f-stops, written f/2.8, f/5.9 and so on, with smaller numbers denoting wider apertures. If you find this inverse relationship tricky to remember, imagine instead that it relates not to the size of the hole but the amount of each fin encroaching into the opening.

A narrow opening is regulated by a large amount of each fin encroaching into the barrel, and so has a high f-stop number, such as f/16, f/18 and so on. A wide opening is characterised by a small number, such as f/3.2, with only a small amount of each fin obscuring the light.


Whether photography is a hobby or a profession, you'll get a whole lot more out of it if you understand how it works. With a firm grasp of aperture, shutter speed, sensitivity and focal length, the ratio of truly great to merely mediocre shots you download at the end of an expedition is all but guaranteed to climb.

Here we present CNET UK's 50 essential shooters' tips. Don't uncap your lens without them.
Aperture

1. Understand aperture
The most fundamental element any photographer should understand is aperture. The aperture is the physical opening within your lens that allows light through to the sensor (or film in an older camera). The wider the aperture opening, the more light can pass through, and vice versa.

The size of the opening, which is regulated by a series of fins encroaching from the edge of the lens barrel, is measured in so-called f-stops, written f/2.8, f/5.9 and so on, with smaller numbers denoting wider apertures. If you find this inverse relationship tricky to remember, imagine instead that it relates not to the size of the hole but the amount of each fin encroaching into the opening.

A narrow opening is regulated by a large amount of each fin encroaching into the barrel, and so has a high f-stop number, such as f/16, f/18 and so on. A wide opening is characterised by a small number, such as f/3.2, with only a small amount of each fin obscuring the light.

Picture the size of the fins, visible here inside this lens, when trying to understand the concept of f-stops.

2. Aperture measurements
Lenses almost always have their maximum aperture setting engraved or stamped on one end of the barrel. On a zoom lens you'll see two measurements, often stated as f/3.5-f/5.9 or similar.

Rather than being opposite ends of a single scale these describe the maximum aperture at the wide angle and telephoto (maximum zoom) lens positions respectively. Always buy a lens with the smallest number you can afford in each position.

3. Avoid using aperture to compensate for poor lighting
Changing the aperture has a dramatic effect on the amount of light coming into the camera, as we have already said. You'll notice this is the case when shooting landscapes with a narrower aperture (higher numbered f-stop) as your camera will often want to take a longer exposure -- so much so that you may have to use a tripod to avoid motion blur.
4. Use a wide aperture for portraits
Anyone with a cat knows that when they're hunting or playing their irises contract to enlarge the size of their pupils. This has the same effect as widening the aperture in a camera lens: it makes the subject they are focusing on very sharp while causing everything behind and in front of it to blur. We call this a shallow depth of field. This is perfect for portrait photography, as it draws forward your model within the scene, making them the central focus while the background falls away. Choose f/1.8 or similar wherever possible.
5. Use a narrow aperture for landscapes
For landscapes, on the other hand, you want to have everything from close-at-hand foliage to a distant mountain in focus. This is achieved by selecting a narrow aperture. If possible stray towards f/22, or whatever the tightest setting your camera allows.
6. 'f/8 and be there'
Static models and immobile landscapes are easy to shoot as you can predict with a great deal of certainty which aperture setting you need to get the best out of either. Reportage and street photography, weddings, Christenings and so on are less predictable as your subjects will be moving in relation to the frame. In these circumstances, adopt the pro photographer's adage, "f/8 and be there".

Set your aperture to f/8 for a practical, manageable balance of fairly fast shutter speeds and broad depths of field, allowing you to spend more time thinking about composition within the frame than you do about optical algebra. When shooting indoors without a flash, and depending on the lighting conditions, you may need to increase your camera's sensitivity setting at this aperture, but be careful not to push it so high that you introduce grain into your images, unless you are chasing that specific effect.
7. What does the ø symbol on my lens mean?
After the focal and aperture ranges, the other measurement you'll see on most dSLR lenses is preceded by ø and describes the diameter of the screw mount on the front of lens barrel. Check this number each time you head out to buy a filter or hood as you can't guarantee that it will be the same for each lens in your collection, even if they are all designed to be used on the same camera.
8. If you only buy one filter...
...make it a circular polariser. This is the perfect beginner's filter, and one that will have the biggest effect on your day to day photography, giving holiday skies a vibrant blue tone and accentuating the contrast between the sky and passing clouds to afford your images greater texture. Although you can add blue to your images in Photoshop or a similar post-production editing tool, the effect is never as believable when done that way as it is when shot using a lens.

Invest in an inexpensive circular polariser to improve the blue of skies in your images.

9. Don't confine it to skies
Polarising filters also cut through glare and reflection. Use it to shoot through windows and water.

We used a polarising filter when shooting this frame to cut through reflections on the surface of the water.

10. Look for lenses where the zoom control doesn't change the filter orientation
Rotating a circular polarising filter changes the strength of the polarising effect, making skies deeper or lighter, and changing the amount of reflection they cancel out. If you plan on using such a filter then wherever possible buy lenses where turning the zoom control doesn't simultaneously rotate the end of the lens, and with it the filter, as this will change the effect. If you have no choice, set your zoom first and adjust the effect afterwards, being careful not to throw the lens out of focus in the process.

11. Don't forget about white balance
When using a filter set your the white balance on your camera to the appropriate conditions, rather than auto, to stop the camera compensating for the filter in front of the lens.

Make sure you set your white balance manually when using a filter.

12. Don't rush out to buy a skylight filter
Putting a clear filter on the front of your lens to protect its surface sounds like a great idea. After all, your lens was an expensive investment. The end of your lens is stronger than you might think, however, and easy to clean if you don't let the dirt build up. Dispensing with a skylight filter will not only save you money, but also avoid the chance of introducing light problems due to increased reflections or the slight reduction in the level of illumination reaching the sensor.

13. Cheat's macro mode (add-on filters)
Dedicated macro lenses are expensive, but you can quickly and easily improve your existing lens' macro credentials by using screw-on magnifiers. They're not a perfect solution as they decrease the level of light coming into the lens, but for occasional work they are very effective, easily sourced and cheap. We bought ours, below, first-hand from eBay, where you should expect to bid around £15 for a set of four screw-on filters.

If you can't afford a dedicated macro mode, you can achieve the same result using an inexpensive set of add-on magnifiers.

14. Avoid stacking up too many filters
It's tempting to add multiple filters to the end of each lens to achieve different results, but bear in mind that although they may look perfectly clear to you, each one reduces the amount of light passing through by a small amount. For the best results, use the smallest number of filters possible.

15. Choose a manual lens over a powered one
Some compact interchangeable lens cameras come with a choice of powered or manual zoom. The former is a great lazy option, allowing you to press a button to get the framing you're after, but the latter is often cheaper and almost always quicker to use as it moves at whatever speed you turn it, without being hobbled by the speed of an internal motor. You can also often make finer and more predictable changes when zooming manually than you can with a powered zoom rocker.

16. Shoot slowly, zoom quickly... At the same time
If you're shooting a static display, add some interest by turning the zoom control while shooting with a fairly slow shutter speed (you can only do this with a manual zoom, as a powered lens will be locked off when shooting). This works particularly well when shooting cars and other forms of transport as it gives them a sense of motion.

Give static subjects added dynamism and excitement by changing the zoom while using a slow shutter speed.

17. Try a prime lens for more creativity
Shooting with a fixed focal length -- a prime lens -- will make you think more carefully about how you want to frame a subject to tell a particular story. It will often also get you a cleaner, sharper result.

18. What do the measurements on my lens mean?
Lenses are measured in terms of their focal length, which broadly describes the effect they have on incoming light and the way it is focused on the sensor. A short focal length, such as 24mm, doesn't have a very high level of magnification, so will focus a broad vista on the sensor. A long focal length, such as 240mm, has a high level of magnification, like a telescope, and so will fill the sensor with just the central part of the view.

This lens has a fairly long telephoto with the zoom topping out at 300mm.

19. Understand your lens' true dimensions
Unless you've paid for a high-end dSLR, or a professional camera such as the Leica M9, your pocket snapper's sensor will almost certainly be smaller than a frame of 35mm film, the standard point of reference against which all focal lengths are measured.

The 35mm in a frame's name actually relates to the space between the top and the bottom of the film strip, which as well as the frame itself also contains some border areas and the sprocket holes used to move the film through the camera. A 35mm frame is positioned lengthwise on this strip, with its shortest dimension -- top to bottom -- perpendicular to the film's direction of motion. As such, neither the height nor the width of the frame measures 35mm, but instead 24x36mm.

To understand how the stated focal length on any lens will affect the shot captured by your camera, you need to factor in the multiplier effect, which converts the size of your sensor to the size of that 35mm piece of film. The multiplier is often between 1.5 and 1.7 but varies between manufacturers and models.

So, if you're buying a lens for the Canon EOS 600D with its 22.3x14.9mm sensor you'd need to multiply the stated focal length of the lens by 1.6. This would make a 50mm lens, commonly used in portrait photography, act like an 80mm lens, thus increasing the effective zoom and narrowing the amount of the scene seen in each frame. On a Nikon D5100, which has a slightly larger sensor (23.6x15.6mm) you'd need to multiply the lens' measurements by 1.5, in which case an equivalent 50mm lens would act as though it were a 75mm unit.

20. Save money by opting for a smaller sensor
This means you can, technically, save money by opting for a smaller sensor, as you'll be able to buy less powerful lenses to achieve the kind of results you would otherwise only get with a longer, more expensive zoom.

21. Use zone focusing
Related to point 6 -- f/8 and be there -- if you have a lens with both f-stop and focal measurements on the barrel, understanding how they relate to each other can help you take great spontaneous photos with a high degree of confidence.

In the image below we've set our aperture to f/5.6, as indicated by the red line pointing to the 5.6 reading on the lower gauge. We've then set the range on the yellow gauge to around 1.2 metres by positioning this at the top of the same line. We can now use the green scale to understand how far away from the camera our subjects need to be if they are to be accurately focused.

By following the lines running from the two green entries for 5.6 on either side to their measurements on the yellow scale, we can see that so long as we're more than 1m away from our subjects they will be in focus (the green 5.6 on the left is linked to around 1m on the yellow scale, while the green 5.6 on the right is linked to the infinity symbol, which is like a number 8 on its side). Anything closer than that will be blurred.

This gives us a great deal of freedom to snap whatever we want without making any further adjustments, so long as it's no closer to us than 100cm. To create a more intimate effect, adjusting the distance ring so that 0.4 sat at the top of the red marker would mean that only those objects between around 36cm and 50cm would be kept in focus.

Use zone focusing to understand which parts of your image will be in focus at any particular aperture setting.
Lighting

22. Invest in a cheap pair of lights
If you're doing any kind of indoor photography, invest in a cheap pair of lights. Buy at least a pair, complete with tripod stands and reflectors to direct the light. Opt for continuous light rather than flash units, as they're cheaper, easy to use and great for beginners, as you don't have to take test shots to see how the shadows fall during setup.

23. Understand colour temperature
Different colours and levels of light are measured using the Kelvin scale. For the best results, look for studio lights with a temperature of around 5,500K-6,000K to emulate bright daylight. Lights with a lower colour temperature often render a colour caste in your images that will have to be corrected in Photoshop or an alternative image editor.

This professional studio bulb maintains a constant colour temperature of 5500K, as specified on the furthest end.

24. Buy a light box -- but don't spend more than £20
Minimise shadows in your studio-lit work by investing in an inexpensive light box. Effectively a five-sided cube with gauze sides and top, you position your lights so that they shine through the sides of the box, diffusing the light and softening the shadows. Light boxes usually ship with a felted back cloth that can be attached using Velcro to create an infinite field of view by obscuring the seams of the box.

An inexpensive light box makes it easy to shoot with artificial light without casting strong shadows.

25. Make best use of available light with a sheet of paper
If you can't afford studio lights, even out harsh contrasts when shooting with natural light by positioning a large sheet of paper or card to reflect the incoming light onto the unlit side of your subject. If shooting people, ask them to hold the card themselves outside of the framed shot. Alternatively, invest in a set of reflectors. You can pick up a new, multi-part set with white, silver and gold reflective surfaces for around £12 on eBay.

This shot would have benefitted from a reflective surface positioned to the left of the frame to illuminate the right-hand side of our subject's face.

26. Don't be dictated by the sun
Using automatic settings to shoot into the sun will throw your subject into silhouette as the camera dials down the exposure to compensate for the bright background. Shooting people with the sun in front of them, meanwhile, solves the silhouette problem but introduces another one: squinting. Solve this by keeping their back to the sun and forcing the flash to fire (switch from it 'auto' to 'on' or 'forced') to correct the exposure on your subjects' faces without leaving them squinting.

27. Observe the rule of thirds
The most aesthetically pleasing images are those in which the subjects are aligned with the one-third power points in every frame. Position horizons one third up or down the height of the image, and people one third in from the left or right. Likewise, if you're snapping a frame-filling head shot, position the eyes so they're one third down from the top of the frame.

Some cameras give you the option of displaying an overlaid grid on the rear LCD to help you line up your subjects along these lines. If yours does, go one step further and put key elements on the points where the horizontal and vertical lines intersect.

Here we've added short red ticks to the top and the bottom of this frame to show how the man warming his drum is positioned one third of the way in from the right of the frame, and the flames of the fire are one third of the way in from the left.

28. Exposure and focus come first, framing second
Half-pressing the shutter release fixes the focus and exposure settings for the shot you're about to take. Pressing it all the way captures the frame.

Use this to your advantage by metering for particular conditions by putting your subject on one of your camera's focus positions and half pressing the shutter to lock its settings then, without releasing the button, recompose the framing to align your subjects on the one-third power positions. This way you'll get perfect exposures every time, whatever the composition.

29. Use your free light meter
If you don't have a light meter, use your camera's auto mode to gauge the optimum settings, even if you don't want an immaculately exposed result. Examine the shot's settings and then switch to manual mode and replicate them before pushing individual elements -- shutter speed, sensitivity, aperture and so on -- to achieve the moody result you're after.

Let your camera do the hard work: take a picture in auto mode and use its self-selected settings as the basis for your manually dialled variables next time around.

30. Get up early, stay out late
Photography is all about painting with light. Light is what gives your pictures contrast, shape and texture, and often the best light it that which appears at either end of the day when the sun is lower in the sky. At these times of day it casts longer, more extreme shadows, which in turn pick out small details, bumps and texture.

By shooting early in the morning and late in the afternoon, you'll achieve far more interesting results than you would at high noon when you'll spend more time controlling the light coming into your lens than you will manipulating your subjects to best exploit the shadows.

It's a cliche, but this shot of Whitby Abbey wouldn't be nearly as atmospheric if it weren't taken at sundown.

31. Embrace the grey day
Don't let an overcast day put you off heading out with your camera. The softer light you get on an overcast day is perfect for shooting plants, flowers and foliage as it dampens the contrasts we were championing in our previous step. This allows the camera to achieve a more balanced exposure and really bring out the colours in petals.

Overcast days present the perfect conditions for shooting flowers and foliage.
Cheat's tips

32. Travel without a tripod: tip 1
Packing a tripod when you head off on holiday is a great way to extend the shooting day, allowing you to take some stunning night-time shots with streaking lights and illuminated landmarks. If you're pushed for space, though, check out this trick. Balance your camera somewhere sturdy and safe, disable the flash and set a slow shutter speed or two seconds or more.

Now set your self timer, fire the shutter release and let go of your camera so that you won't cause it to wobble. By the time the self timer countdown expires, any residual movement caused by your hand letting go should have evened out, so your camera will sit still and steady throughout the exposure for a crisp, sharp result.

We took this using the self timer and a long exposure. Avoid the temptation to squat in Rome's rush hour traffic.

33. Travel without a tripod: tip 2
It's not always possible to find a flat surface on which to perform the previous trick. Try and find a flat surface on some castle battlements and you'll see what we mean. Combat this by packing a small beanbag in your camera bag.

Check out school sports and games categories on eBay to find 100g beanbags (a pack of four costs less than £5), which can be pressed into shape on uneven surfaces, with your camera snugly settled on top. It's more stable and less likely to either fall over or wobble during the exposure.

Paris this time, and we're once again employing the delayed shutter trick.

34. Travel without a tripod: tip 3
Professional tripods use quarter-inch screws to fix your camera in place. You can easily source a screw of the same size from a normal hardware store. To avoid travelling with a bulky tripod, drill a hole in a standard bottle top (the type you'd find capping a 500ml drinks bottle) and thread the screw through it, fixing it in place using strong glue.

Keep this in your camera bag as you travel, but don't bother carrying the rest of the bottle, as these are easily sourced wherever you happen to end up. Fill an empty bottle with grit to give it some weight and screw your cap to the top. Instant tripod.

35. Banish long-arm self portraits
Self portraits are great for capturing holiday memories, but if you can't find somewhere suitable to balance your camera while also framing the scene behind you, the only way you can take them is to hold your camera at arm's length and press the shutter release. The results are rarely flattering.

Invest in a cheap monopod (search eBay for handheld monopod) and use this to hold your camera away from you while keeping your hands in a more natural position and the great scenery you want to stand in front of behind you. Use your camera's self-timer to fire the shutter 2 or 10 seconds later.

Your author in Greece, without the aid of a monopod, where the arm and watch strap somewhat distract from the Acropolis.

36. Look at the eyes, not around the eyes, look at the eyes
Ever wondered why so many magazines have faces on the cover? It's because we identify with such pictures, which in turn helps us identify with the magazine. Art editors know that our inclination is to connect with the eyes staring out of the cover, and the same is true of your portraits.

When shooting a person, if only one part of your image is in focus, make it the eyes. That's the first place your audience will look. So long as they're in focus, they'll consider the whole image to be accurately shot, no matter how shallow your depth of field and how blurred the rest of the frame.

The eyes are in focus in this shot, so we read it as being accurately focused overall.

37. Use burst mode when shooting pets
Pets are unpredictable, so don't wait for them to pose before shooting. The chances are you'll miss the crucial moment.

Don't wait until you've attracted their attention -- start shooting while you're trying to do it, as they don't understand the concept of cameras and will move at the worst possible moment. Switch your camera to burst mode and start shooting while you're trying to attract their attention towards the lens for a better chance of capturing something close to the picture you wanted.

Use burst mode when shooting animals and pets to increase your chances of capturing the shot you're after.

38. Make use of scene modes
Your camera knows better than you do how to use its own settings to create special effects. Don't be afraid to use its in-built scene modes for punchy monochrome or high-key effects. If possible, set your camera to save raw and JPEG images side by side so you also have a copy of the original unadulterated scene should you later change your mind.

39. How to shoot fireworks
Frequently the most impressive spectacle, fireworks are nonetheless tricky to shoot. For your best chance of capturing a display, set your sensitivity to ISO 100 and compensation to 0EV so that you don't unnecessarily lighten the sky, which you want to keep as black as possible.

Mount your camera on a tripod and set your shutter speed to at least 8 seconds. Zoom out so that the fireworks just fill the frame, preferably without being cropped by the borders and be careful not to wobble the camera during the exposure or you'll end up with blurred results. All being well, the result should be pin-sharp streaks of light falling to the ground.

We shot these fireworks using an 8-second exposure with the help of a tripod and timed shutter release.

40. How to shoot moving water
Short shutter speeds do a good job of capturing a waterfall and its surroundings, but you'll achieve a far more attactive result by slowing things down. To do this without overexposing your image, start by switching out of auto and reducing your camera's sensitivity to its lowest setting (usually around ISO 100 or ISO 80), then either use a neutral density (ND) filter or, if you don't have one or can't fit one to your camera, dial down the exposure compensation to its lowest level (usually -2EV, -3EV or -5EV).

Mount your camera on a tripod, half press the shutter release to fix the focus point and exposure and then press it all the way to take the picture, being careful not to shake the camera while it's taking the shot. It'll take some experimentation to get this right, so don't be put off if you don't get the perfect results first time around.

By taking this picture with a slower shutter we've softened the water both in the waterfall and passing in front of the lens.

41. Focus on the details
When a scene is simply too big to fit in your picture without it getting uncomfortably close to the edge of the frame, focus instead on one of the details that makes it unique. An abstract crop can often have greater impact and give a more original view of a tired, over-used view we've all seen before.

Zoomed and cropped: an unusual night-time view of the Louvre Pyramid, reflected in the pools that surround it.

42. You can't shoot speed head-on
You can't properly capture speeding subjects as they come towards or move away from you. If you're shooting track events, position yourself side-on to the action so that it passes across your field of view rather than coming towards it. Shooting into a chicane works well on TV where we delight in seeing the cars snake around it in sequence, but fares poorly in static frames.

43. Focus on the action
If you really want to convey an impression of speed in your images, pan your lens in line with speeding cars, horses and runners and shoot with a fairly slow shutter speed -- 1/125 second or below -- to blur the background. Keeping the subject sharp in the frame while blurring the background gives a more effective impression of speed than static backgrounds and blurred subjects.

44. Reflect on things
Do rainy days and Sundays get you down? Don't let them: embrace the photo opportunities afforded by the puddles. The rain is as much a part of the story of your holiday as the food you ate and the sights you saw. Use reflections wherever possible for a different take on otherwise well-known scenes.

Even ugly urban decay can sparkle with the help of a reflective puddle.
Smart shopping

45. Don't believe the megapixel myth
We're glad to see manufacturers are starting to see sense here, with many high-end cameras now sporting comparatively modest pixel counts. At the lower end, however, some manufacturers continue to cram 16 megapixels and more on tiny sensors that can't cope with high levels of incoming light. Pay for quality, not quantity, remembering that as few as 10 megapixels is plenty for printing at A3 using online photo-printing services.

This squirrel was shot using the 10.1-megapixel Nikon 1 J1. Despite the conservative resolution, the quality is great and we'd be happy to print this as a poster to pin on the wall.

46. Flickr: your shopping assistant
Baffled by numbers and stats? If you can't get your hands on a camera to try before you buy, at least have a look at the shots it produces. Flickr uses the metadata attached to every photo shot by a digital camera to catalogue them by manufacturer and model, allowing you to click through a representative sample of output in its enormous online archive. Find it at flickr.com/cameras.

47. Don't be a memory cheapskate
Buy the fastest memory cards you can afford to minimise the time it takes for your camera to write each shot to the media, and how long you'll have to wait before you can take the next shot. Wait too long and you'll miss something.

Cards are ranked using a simple class system, where the class number is simply the number of megabytes the card can store per second. So, your camera will be able to write to a Class 4 card at up to 4MBps, and a Class 10 card at up to 10MBps. Faster cards are more expensive, so if you're having trouble justifying to yourself the extra expense, compare them to the speed boost you get from upgrading the memory in your PC or Mac.

This Class 10 card is the fastest you can get, minimising the time you'll have to wait between taking multiple sequential shots.

48. Size really is everything
Think carefully about how you want to balance the convenience of carrying fewer large cards with the security of travelling with a larger number of lower capacity ones. On the one hand you'll spend less time swapping 16GB cards than 2GB media, but if you lose a single 16GB card, or it corrupts, you could lose all of the shots from your trip.

Splitting them across several cards, and locking full cards in your hotel safe so you're only carrying around empty cards plus the one on your camera means you'll be taking fewer risks with your digital memories.

Travelling with several smaller cards than one large card means you can lock your photos in a room safe while out and about.

49. Replace your cards every couple of years
Memory cards might not have any moving parts, but that doesn't mean they don't wear out. On the contrary they each have a finite life, and every time you write to, delete from or read the card you're bringing it another step closer to the end of that life. If you don't want to risk corrupting your pictures far from home, replace heavily used cards every couple of years.
And finally...

50. Break all the rules
Be truly original. Ignore the rule of thirds. Shoot at high noon. Shoots sports photos at slow shutter speeds for blurred results. Whatever you do, make your pictures stand out from the crowd and relish the results.

Monday, September 16, 2013

INTERNET SOME IDEAS

Now a days, most of the people in the society depend upon Internet. They may not have the knowledge of basic ideas of terms, just have a look here to know 7 basic concepts of INTERNET
1. The Web vs. the Internet:

The Internet is a vast 'inter-connection of computer networks' that spans the globe. It is comprised of millions of computing devices that trade volumes of information. Desktop computers, mainframes, GPS units, cell phones, car alarms, video game consoles, and even soda pop machines are connected to the Net.
The Internet started in the late 1960's as an American military project, and has since evolved into a massive public spiderweb. No single organization owns or controls the Internet. The Net has grown into a spectacular mishmash of non-profit, private sector, government, and entrepreneurial broadcasters.
The Internet houses many layers of information, with each layer dedicated to a different kind of documentation. These different layers are called ' protocols'. The most popular protocols are the World Wide Web, FTP, Telnet, Gopherspace, instant messaging, and email.
The World Wide Web, or 'Web' for short, is the most popular portion of the Internet. The Web is viewed through web browser software.
Grammar and spelling note:
Use capitalized 'Internet' and 'Web' when using either word as a noun. Use lowercase 'internet' or 'web' when using either word as an adjective. e.g. 'We were browsing the Internet last night.' e.g. 'We found a really good web page about global warming.'

2. http and https:

http is a technical acronym that means 'hypertext transfer protocol', the language of web pages. When a web page has this prefix, then your links, text, and pictures should work in your web browser.
https is 'hypertext transfer protocol SECURED'. This means that the web page has a special layer of encryption added to hide your personal information and passwords. Whenever you log into your online bank or your web email account, you should see https at the front of the page address.
:// is the strange expression for ' this is a computer protocol'. We add these 3 characters in a Web address to denote which set of computer lanaguage rules affect the document you are viewing.

3. Browser:

A browser is a free software package that lets you view web pages, graphics, and most online content. Browser software is specifically designed to convert HTML and XML into readable documents.

4. HTML and XML:

Hypertext Markup Language is the programmatic language that web pages are based on. HTML commands your web browser to display text and graphics in orderly fashion. HTML uses commands called 'HTML tags' that look like the following:
*.

*.SANATHANA

XML is eXtensible Markup Language, a cousin to HTML. XML focuses on cataloging and databasing the text content of a web page. XML commands look like the following:
*.
*.
*.
XHTML is a combination of HTML and XML.
5. URL:

URL's, or 'uniform resource locators', are the web browser addresses of internet pages and files. A URL works together with IP addresses to help us name, locate, and bookmark specific pages and files for our web browsers.
URL's commonly use three parts to address a page or file: the protocol (which is the portion ending in '//:'); the host computer (which sometimes ends in .com); and the filename/pagename itself. For example:
www.facebook.com
6. IP Address:

Your computer's 'internet protocol' address is a four-part or eight-part electronic serial number. An IP address can look something like ' 202.3.104.55' or like '21DA:D3:0:2F3B:2AA:FF:FE28:9C5A', complete with dot or colon separators. Every computer, cell phone, and device that accesses the Internet is assigned at least one IP address for tracking purposes. Wherever you browse, whenever you send an email or instant message, and whenever you download a file, your IP address acts like a type of automobile licence plate to enforce accountability and traceability.

7. ISP:

ISP is Internet Service Provider. That is the private company or government organization that plugs you into the vast Internet around the world. Your ISP will offer varying services for varying prices: web page access, email, hosting your own web page, hosting your own blog, and so on. ISP's will also offer various Internet connection speeds for a monthly fee. (e.g. ultra high speed Internet vs economy Internet).
Today, you will also hear about WISP's, which are Wireless Internet Service Providers. They cater to laptop users who travel regularly.

Tuesday, September 3, 2013

HOW DOES A DC MOTOR WORKS??

Most of us are familiar with DC motors. Do you know how a DC motor works?
A DC motor works by converting electric power into mechanical work. This is accomplished by forcing current through a coil and producing a magnetic field that spins the motor. The simplest DC motor is a single coil apparatus, used here to discuss the DC motor theory.

The voltage source forces voltage through the coil via sliding contacts or brushes that are connected to the DC source. These brushes are found on the end of the coil wires and make a temporary electrical connection with the voltage source. In this motor, the brushes will make a connection every 180 degrees and current will then flow through the coil wires. In the 0 degrees, the brushes are in contact with the voltage source and current is flowing. The current that flows through wire segment C-D interacts with the magnetic field that is present and the result is an upward force on the segment. The current that flows through segment A-B has the same interaction, but the force is in the downward direction. Both forces are of equal magnitude, but in opposing directions since the direction of current flow in the segments is reversed with respect to the magnetic field. In the 180 degrees, the same phenomenon occurs,but segment A-B is forced up and C-D is forced down. In the 90 and 270-degree, the brushes are not in contact with the voltage source and no force is produced. In these two positions, the rotational kinetic energy of the motor keeps it spinning until the brushes regain contact.

Thursday, August 29, 2013

Indian Culture

Culture is a symbolic, continuous, cumulative and progressive process. In the words of Green, culture means "the socially transmitted system of idealized ways of knowledge, practice and beliefs along with the artifacts that knowledge and practices produce and maintain as they change times."

Culture is the short-hand version of the rules that guide the way of life of people. It is the common learned way of life shared by members of a society. In a word, culture is the expression of finer aspects of the life style of a group. As Johann Von Herder says, "the culture of a people is the blood of its being."

In the famous words of Arnold J.Toynbee, "civilization is a movement - not a condition, a voyage and not a harbour." This is true especially in the context of India. Though one of the oldest of ancient civilizations, India is the only example of a continuous process of the growth and evolution of its ancient civilization. In a word, Indian civilization is a continuum and, therefore, unique. As such, the culture of India has always been integral in its approach. '

It has never been one-sided. One of the greatest scholars on the culture of India, Basham has this to say on the subject,".... in no other part of the ancient world were the relations of man and man, and of man and the state, so fair and humane. In no other early civilization were slaves so few in number, and in no other ancient lawbook are their rights so well protected as in the Arthasastra. India was a cheerful land, whose people, each finding a niche in a complex and slowly evolving social system, reached a higher level of kindliness and gentleness in their mutual relationships than any other nation of antiquity."

Thursday, August 22, 2013

GREEN CHEMISTRY

IMAGINE a world in which – instead of toxic solvents and chemicals – industrial manufacturing used sugar, starch and sunlight as inputs. Imagine products that biodegrade into utterly benign substances. Imagine pure, clean water leaving factories and polluted sources brought back to life. What if industrial chemicals were bio-based and generated by farmers practicing sustainable agriculture? Imagine a workplace free of “hazmat” gear, factories without scrubbers, and a world where CO2 is used as a valuable industrial input rather than emitted as a green house gas. Green Chemists are making this vision a reality.
Biopesticides are a set of tools and applications that can help farmers transition away from highly toxic conventional chemical pesticides into an era of truly sustainable agriculture. Biopesticides of course are only a part of a larger solution; sustainable agriculture is a wide field. But helping farmers move from the current chemical dependency to sustainable agriculture and beyond requires tools for the transition and for a new era. Biopesticides can and will play a significant role in this process.

Like other Green Chemistry solutions, developing safe, effective biopesticide products requires holistic thinking and multi-disciplinary approaches which are a challenge for the biopesticide industry. Turning lab discoveries into profitable business products is also daunting. This mirrors what inventors face when implementing green chemistry solutions in other sectors. What follows is a summary of conclusions:
Transparency and dialogue are essential.
Broader questions of hazard are sometimes poorly understood.
Efficacy is key.
Multi-disciplinary teams are essential for moving from active ingredient to product.
Sometimes promising green chemistry discoveries sit neglected on the shelf.
Banning bad actor chemicals can be a powerful driver.
Biopesticides offer growers both opportunities – and challenges.
Conclusion

Serious questions remain about the safety of biopesticide products from both a human and ecosystem health standpoint. Current regulations do not go nearly far enough in evaluating systemic broader impacts of biopesticides. By definition, Green Chemistry is about continuous improvements aimed at reducing or eliminating hazard. Fully defining hazard is difficult. Even products hailed by Green Chemists and regulators alike as safer for human health may turn out to have unforeseen negative environmental health impacts. See for example, Spinosad, a green chemistry award winning biopesticide, which while significantly safer for humans than other pesticides but is toxic to bees.

We must encourage pest management solutions and regulations to continuously evolve. We must also ensure that multi-disciplinary teams, including Green Chemists, environmental health specialists and other scientists, approach these innovations holistically.

Biopesticides – Examples


Biopesticides offer powerful tools to create a new generation of sustainable agriculture products. They are the most likely source for alternatives to some of the most problematic chemical pesticides currently in use. Biopesticides also offer solutions to concerns such as pest resistance to traditional chemical pesticides, public concern about side effects of pesticides on the surrounding environment and ultimately, on human health.

The overriding challenge for the biopesticides industry is to live up to the promise that the field holds. There are unanswered questions and un-examined assumptions about them with which those involved must contend. Challenges to biopesticides stem from questions about their efficacy and safety, public and grower confusion about the spectrum of biopesticide products on the market, and current market conditions that paradoxically both hinder and favor the field’s growth.

These stories highlight some of the successes and challenges for expanding use of biopesticides.

The Challenge of Commercialization for Niche Products. A look at economic and regulatory challenges and opportunities impacting commercialization of biopesticides alternatives due to their niche market applications.

Mating Disruption as a Pest Managment Tool. This example demonstrates the complexity of both developing and using biopesticides

An Alternative to Methyl Bromide: “Pasteuria” for Nematode Control. A technological advance significantly decreased the cost of production, making the product economically viable.

Large-scale Production of Baculovirus Isolate. A look at the greater production complexity (and potential costs) of developing a biopesticide.

The Challenges of Product Formulation, Proprietary Ingredients and Community Dialogue: The Light Brown Apple Moth. Success for the field of biopesticides will require greater transparency in research, design, and application.

Niche Marketing as an Opportunity for Competitive Differentiation “Bioworks”. This case illustrates how biopesticide companies can position themselves for success within a shifting paradigm.

Codling Moth Control- Regulatory Changes Can Drive Innovation (and Lack of Regulation Can Stymie It). Shifting to more sustainable agricultural practices rarely is as simple as a one to one replacement of an existing pesticide.


Monday, August 19, 2013

HOW DOES INVERTER WORK?

Everyone uses some kind of electronic gadget while in their motor-home, SUV or car. You might listen to your MP3 player, check for directions on your global positioning system (GPS) or play a portable video game. These types of electronic devices can be recharged or powered by plugging them into the cigarette lighter (or power port) in your vehicle.

But what if you want to use something a little more elaborate while you're on the open road? Maybe you want to make toast, watch an LCD TV, or perhaps even write an article on your laptop computer. These devices plug into regular wall outlets, not cigarette lighters. Making sure your electronic gear gets the juice it needs while on the road isn't a simple matter of finding the right adapter. You need a power inverter.

­Power inverters convert direct current (DC), the power that comes from a car battery, into alternating current (AC), the kind of power supplied to your home and the power larger electronics need to function. What kind of power inverter is the right one for the job? How do you install one? And how exactly does an inverter change the current from one form to another? In this article, we'll explore all the positives and negatives of DC to AC power inverters.
Why Do I Need To Convert from DC to AC?


Most cars and motor homes derive their power from a 12-volt battery. In some cases, a heavy-duty 24-volt battery might be used. It's important to know your vehicle's voltage because the voltage rating of the inverter you select should match the voltage of the battery. In either case, the battery provides direct current. This means that the current flows continuously from the negative terminal of the battery, through the completed circuit and back to the positive terminal of the battery. The flow is in one direction only, hence the name direct current. The ability to provide direct current power is inherent to the nature of batteries.


Direct current is very useful, but batteries can generally only provide relatively low-voltage DC power. Many devices need more power to function properly than DC can provide. They're designed to run on the 120-volt AC power supplied to homes in the U.S. Alternating current or AC, constantly changes polarity, sending current one way through the circuit, then reversing and sending it the other way. It does this very quickly -- 60 times per second in most U.S. electrical systems. AC power works well at high voltages, and can be "stepped up" in voltage by a transformer more easily than direct current can.


An inverter increases the DC voltage, and then changes it to alternating current before sending it out to power a device. These devices were initially designed to do the opposite -- to convert alternating current into direct current. Since these converters could basically be run in reverse to accomplish the opposite effect, they were called inverters.

Making Direct Current Alternate


The earliest AC power inverters were electro-mechanical devices. Direct current would flow down one end of a circuit with an electromagnet. As soon as the current hit the magnet, the magnet would activate. This would pull a wire attached to a spring arm, forcing the wire to contact the circuit. This would change the flow of the current to the other side of the circuit, cutting power from the electromagnet. As soon as the magnet released, the spring would snap the wire back, allowing the current to flow on the other side of the circuit, once again activating the magnet. These old inverters were known for making a buzzing sound.

Modern inverters use oscillator circuits to accomplish the same process. They're made with transistors or semiconductors, so there's no longer the need for a spring arm flipping back and forth to alternate the current.

It's not quite as simple as that, however. Alternating current forms a sine wave. The output of an inverter is a very square wave, not like the smooth, round wave of a perfect sine. Some devices are inherently sensitive to the signal produced by an AC wave. Typically, these are devices that receive or broadcast some kind of signal, such as audio or video equipment, navigation devices or sensitive scientific equipment. You can see or hear the square waveform on a television as lines on the screen or a steady buzz or hum.

Cleaning up the sine wave requires a series of filters, inductors and capacitors. Inexpensive inverters have little or no filtering. The alternating current they produce has a very square wave, which is fine if you just want to make coffee or run something with a simple electric motor. If you need a smoother sine wave, you'll need an inverter with better filtering. Of course, better filtering also costs a little more. Inverters can get extremely expensive, even costing thousands of dollars, that is, if you're looking for an inverter with a smooth sine. The good news: Given a large enough budget, you can purchase an AC power inverter that produces virtually perfect AC sines. In fact, some high-end DC to AC inverters can make sine waves that are even smoother than the AC power supplied to your house.

Watts, Peaks and Surges

The first step in selecting an inverter is to match the inverter to the voltage of the battery you'll be using for power. In the majority of cases, you'll be using a 12-volt battery, so you would want to select a 12-volt inverter.

The next step is to determine which devices you plan to power with the inverter. Look for a label somewhere on each device that tells you the wattage it requires to operate. The wattage rating of your inverter must exceed the total wattage of all the devices you plan to run simultaneously. For instance, if you wanted to run a 600-watt blender and a 600-watt coffee maker at the same time, you'd need an inverter capable of a 1,200-watt output. However, if you knew you would never be making coffee and fruit smoothies at the exact same time, you'd only need a 600-watt inverter.

Unfortunately, things aren't quite that simple. Devices that have electric motors, as well as some televisions, draw a higher wattage than their normal operating wattage rating when they first start up. This is known as peak or surge, and this information should also be listed on the device's label. Most inverters also have a peak rating, so make sure the inverter's peak rating is higher than the peak wattage of the device you intend to power. Microwaves are a special case. As an example, you may know that your microwave is a 500-watt microwave. This is actually the cooking wattage. The power wattage might be twice that amount. Again, check the label on the device to make sure.

If you plan to run your inverter through the cigarette lighter in your car, it's a safe bet that you won't be using any high-wattage devices. In fact, if you try to pass more than about 400 watts through a cigarette lighter connection, it will fail -- and it might even start a fire in your vehicle.

The final specification to look for is the wave output of the inverter. If you'll be powering any of the equipment that is sensitive to square waves, look for an inverter with a "perfect sine" wave output. Be prepared for sticker shock -- a perfect sine inverter can cost almost 10 times as much as the same wattage inverter with a modified sine output. Modified sine means that the current is run through some filtering, so it isn't a square wave, but it isn't totally smooth either.


Inverter Installation

Inverters are very easy to install. Most of them are "plug and play" devices, especially smaller, low-wattage inverters. These inverters have a cable with a plug that fits into the cigarette lighter on your car or truck. They're meant to be portable, so there's no other mounting to be done.

­If you purchase an inverter that allows higher wattages, proper installation becomes a bit more critical. Below 400 watts, the cigarette lighter connection is still a possibility, but wattages above that require direct connection to the battery. The inverter's input cables have clips that can be attached to the terminals of the battery, similar to a set of jumper cables. If the installation is to be permanent, the cables can be bolted to the terminals. The inverter itself can be mounted anywhere, although it should be in a place with good air flow. Inverters generate a fair amount of heat, and they use cooling fans and heat dissipation fins to prevent overheating. Larger, heavier inverters have mounting holes in their chassis so they can be bolted to any surface. Obviously, with a permanent installation, you'll probably want to bolt your converter in place, but this isn't absolutely necessary. It's possible to simply place the inverter in a secure, stable position, clip the leads to the battery and plug in.

Just what does an inverter look like, anyway? Well, the smallest inverters can fit in your pocket, while higher-wattage models are roughly the size and weight of a large dictionary. As a general rule: The higher the wattage, the larger and heavier the inverter. At the top of the inverter wattage scale, some inverters can be more than two feet long and weigh over 30 pounds.

Modern inverters have some built in safety features that make them even easier to use. Some models sound an alarm when the battery's voltage gets too low. This is more of a convenience, but depending on what sort of equipment you're powering, it could also be a valuable safety feature. Inverters typically have automatic shut-off capabilities, too. If the unit detects a current overload or an overheating situation, it will shut down to lessen or prevent the chance of a fire. Inverters can also shut off in the event of a short circuit, such as a piece of metal falling into the chassis or the inverter getting wet. Short circuit shut-off is an effective way to prevent electrocution.

So how much is all of this going to cost, you ask? You can buy a modified sine inverter rated for continuous power of 200 watts for about $25 and the price of a 6,000-watt modified sine inverter can approach $1,000. Pure sine inverters cost much more -- these can be more than $200 for an inverter rated at just 300 watts.



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