Flash 101 part 2

Hm…today iam very not in the mood…even skip the class…now i cant even sleep..so i decided to continue for FLASH 101 part 2. Same as before, i would like to give the credit to “Curtis N the Master Flasher” the writer of this article. For those who has missed the previous article FLASH 101 part 1, you can go HERE: FLASH 101 part 1.

You can either read this in my post or you can directly go HERE for the original article. For those who like to read it here, please do continue.

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(WHY) SHOULD I GET A FLASH UNIT FOR MY CAMERA?
A beginner’s guide

Many cameras, including some fairly expensive DSLRs, have a built-in (pop-up) flash unit, as well as a hotshoe for an attached flash unit. Beginners often ask why or if they should buy a separate flash attachment, and this tutorial is designed to answer that question.Which flash should I get for my EOS camera?

I wanted to include some sample images before I posted this, but since I don’t know if/when I’ll ever get that done, I decided to go ahead with the text.

REASON #1: REDEYE
We’ve all seen pictures of people whose eyes have that diabolical red glow. It can ruin an otherwise very good shot. It is caused by light reflecting off the retina in the back of the eye. This phenomenon is worst when the subject’s pupils are dilated (indoors), and when there is a narrow angle between the light source (flash), eye, and lens. Geometrically, the two factors which affect this angle are the distance between the flash and the lens, and the distance between the camera and the subject’s eyes. One way to avoid this problem is to move the flash further from the lens. The more distance there is between the flash and the lens, the further away the camera can be from human subjects without causing red eyes. Typically, a hotshoe-mounted flash unit will be twice as far from the lens as a “pop-up” unit. A flash bracket can be utilized to make this distance even greater.

REASON #2: POWER
The effective distance of any flash is dependent upon the aperture and ISO setting used. For example, at f/8 and ISO 100, the built-in flash on today’s DSLRs will be effective only if your subject is within about 5 feet of the camera. Of course, you can increase this range by opening up the lens and/or using a higher ISO setting, but that comes at a cost – less depth-of-field and more digital noise. A good flash unit has about fifteen times the power of a built-in unit, with perhaps four times the effective distance. This allows the use of smaller apertures (for better depth-of-field) and lower ISO settings (to reduce digital noise). Power is also critical for bounced flash and fill flash in sunny conditions.

REASON #3: BOUNCED FLASH
The ability to point the flash at a wall or ceiling will do more for the quality of flash photographs than just about anything else. It can mean the difference between a harsh-looking “snapshot” and a pleasing photograph that doesn’t even look “flashed”. Illuminating the ceiling has the effect of making the light source much larger, creating softer shadows, a brighter background, and more natural-looking results. The power required for this technique varies widely according to the height and color of the ceiling and other factors, but even with a low, white ceiling it can require as much as four times the power of direct flash. With direct flash, you’re lighting up your subject. With bounced flash, you’re lighting up the whole room!

REASON #4: FLASH MODIFIERS
There are a wide range of “diffusers” and other attachments which somehow modify the direction of some or all of the photons flying out of the flash unit. They can be as simple as a 3 x 5 index card and rubber band. Other attachments include the Lumiquest Promax System, mini softboxes, the Sto-Fen Omni-bounce, and the Lightsphere II. They all work a little differently and they each have their place. Generally they are designed to make the light source larger from the subject’s perspective, or to provide some direct illumination with bounced flash. Another completely different modifier is the Better Beamer, which creates a powerful, narrow beam for long-distance wildlife shooting. When used properly, flash modifiers can dramatically improve flash photographs, but you need a flash unit to use them.

REASON #5: FLASH BRACKETS
Flash brackets come in a variety of styles and serve a dual purpose. In addition to moving the flash unit further from the lens (see reason #1), they also allow the camera to be rotated to vertical orientation while keeping the flash above the lens. This prevents those ugly side shadows on backgrounds which otherwise ruin vertical shots when using a hotshoe-mounted flash indoors. Some styles work by flipping the flash unit, keeping it oriented the same way as the camera. These allow the flash to be zoomed with the lens to avoid wasting light (and power) with direct flash. Other styles allow the camera to rotate while the flash remains over the camera. These make it easier to change orientation while mounted on a tripod, and they work better with some flash modifiers such as the Lumiquest Promax System. Use of a flash bracket requires a sync cord to electrically connect the flash to the camera.

REASON #6: BELLS & WHISTLES
Most good flash units have additional features not available with the built-in. They include:
1)A focus assist light – This light casts a pattern of lines on your subject to allow the autofocus system to work better in low light situations.
2) FP Flash (high speed sync) – This enables the use of high shutter speeds. If you’re using fill flash outdoors and want to use a wide aperture to blur the background, FP Flash is a necessity.
3)Manual mode – This allows you to set and adjust the flash unit’s power, rather than relying on automatic flash metering, and also enables the use of optical slaves. It’s more of an advanced option, but sooner or later you’ll find it useful.
4)Wireless E-TTL – Allows the use of multiple flash units at various power ratios in a master/slave arrangement with E-TTL flash metering.

To summarize, today’s Digital SLRs are packed with amazing technology, and with the right lenses they can produce wonderful images. But the built-in flash units on these cameras are lacking in power, too close to the lens, can’t be tilted for bounce flash and can’t be used with flash modifiers. In short, they rarely produce anything better than “snapshot” quality. Their usefulness is so limited that high-end professional camera bodies don’t even have a built-in flash.

My recommendation to people who buy a DSLR is to buy a good flash unit for it as soon as funds allow. While there are many types of photography that don’t require flash, most beginners photograph people more than any other subject. Flash can improve just about any “people” shot, whether indoors or outdoors. Before you buy another lens, before you get that fancy tripod or any other accessory, buy a good flash unit!

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I hope this information will gave you all, the basic idea of why we should buy a separate flash attachment instead of  just using the build in pop-up flash unit. By putting this article, doesn’t means that I am a good flash photographer, I myself is a beginner and just wanna share the information that I think is good for us (beginner a.k.a noob) :p. So, that is all fot today, for those who find this article is good, and would like to continue for next chapter, just wait for my next post for Flash 101 part 3 and part 4. Or for those who cant wait, you can just visit
HERE and search in the Flash forum in the POTN (photography-on-the-net)

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Flash 101

Hm. Memandangkan hari ni aku agak bosan, nak study pun tngh tak berape ade mood. So aku bace la bab flash. Dah bace dah ari tu, tapi tak bape nak ingat. So aku ingat letak kat blog ni supaye bole kongsi ngan korang gak. Supaye same2 mendapat manfaat…

This article wasn’t written by me. I totally copy it from http://photography-on-the.net/forum and here I provide a direct link to this article. I am not sure whether you need to be a member or not, but if yes, it will be only a simple registration and I guarantee there will be a lot of knowlegde you could gain by joining the forum. Credit will be given to “Curtis N the Master Flasher” (the writer of this article). So enjoy the rest of the FLASH 101 Part 1… (aku pun pening2 lagi bace nih…huhu). Owh, I almost forget, here is the direct link… pls click FLASH 101 or you can just continue reading in my post down here…

THE BASICS

Before you venture into the world of flash shooting, you need to first understand the basics of exposure. This guide assumes that you understand how shutter speed affects exposure and motion blur, how aperture affects exposure and depth-of-field, and how the ISO setting affects exposure and digital noise. If you don’t yet have at least a theoretical grasp of these concepts, then it’s best to learn about them before venturing into the flash world.

Flash fact that every shooter must undertand.

Flash fact #1: Every flash photograph is two exposures in one: an ambient light exposure and a flash exposure. This is a critical fact to remember. The shutter opens, the flash fires, the shutter closes. During this time, both ambient light and flash will contribute to the recorded image. Flash photography requires managing both exposures.

Flash fact #2*: Flash exposure is not affected by shutter speed: The entire burst of light from the flash begins and ends while the shutter is open, so keeping the shutter open longer won’t help with flash illumination. The flash exposure and the effective range of your flash unit will be affected by aperture and ISO settings, but not the shutter. Of course, the ambient light component in a flash photograph is affected by shutter speed. So changing the shutter speed is one way to manage the amount of ambient light that contributes to a flash photograph.
 
Flash fact #3: Flash illumination is dramatically affected by distance: This is known as the inverse square law. Think of it this way: Suppose you’re using a lens that gives you a 4 x 6 ft. field of view at a distance of 10 feet. That same lens will give an 8 x 12 ft. field of view at a distance of 20 feet. So when you double the distance, the same light is covering an area four times larger (96 square feet vs. 24 square feet)! So you need four times as much light to get the same illumination. This phenomenon, sometimes referred to as “flash falloff”, will affect any image with more than one subject at different distances. Whenever your subject distance increases by a factor of roughly 1.4 (the square root of 2), the flash illumination will be cut in half. Suppose you’re taking a large group portrait. The people in the first row are 10 feet away, and the people in the back row are 14 feet away. With on-camera flash as the primary light source, the front row will be a full stop brighter than the back row!
In the image below, each cup is one stop brighter than the one behind it, and one stop darker than the one in front of it. It would take 16 times as much light to properly expose the cup at 11 feet verses the cup at 2.8 feet. Do those distance numbers look familar? They’re the same as standard f/ stops for aperture settings, and the relationship is identical. This thread from PhotosGuy gives an example of how to use this relationship in the field. (the image is currently not available, will be updated ASAP…sorry for the inconvenience).
Flash fact #4: Your camera measures ambient light and flash illumination separately:
In Av, Tv or P modes, it will attempt to expose properly for the ambient light by adjusting either the shutter speed, aperture, or both. The fact that you have your flash turned on has no effect on this** ( one exception is that in P mode it will not use a shutter speed slower than 1/60 with flash). The camera’s metering system cannot predict how much illumination will be gained by the flash, so it doesn’t try. In manual mode, the meter in the viewfinder measures only ambient light, because that’s all it has to measure.
 
Fact 5 refers to any form of automatic flash metering, including older “auto thyristor” flash units, TTL film cameras, and E-TTL or E-TTL II digital cameras.
Flash fact #5: With automatic flash metering, the flash illumination is measured after the shutter button is pressed, and the flash output is adjusted accordingly. There are technical differences between the various types of flash metering, but all of them operate independently from the camera’s metering of ambient light, and all of them work by adjusting the output of the flash, not by changing the camera’s exposure settings.
 
Facts 6 and 7 apply to any camera with a focal plane shutter (all SLR cameras with a mechanical shutter).
Flash fact #6*: Every SLR camera with a mechanical shutter has a maximum flash sync shutter speed(1/200 or 1/250 on current Canon DSLRs). This has to do with the way focal plane shutters work. At slower shutter speeds, the first curtain opens, the flash fires, and after the specified time duration, the second curtain closes behind it. At shutter speeds faster than flash sync, the second curtain begins to close before the first curtain is completely open. The second curtain follows the first across the frame, exposing only a slice of the image at any given moment. Firing a flash during this process would illuminate only part of the image.
 
Flash fact #7*:(Applicable to modern electronic cameras only) If you set your shutter speed faster than flash sync, or use Av mode with an aperture setting that requires a shutter speed faster than flash sync for proper exposure, the camera will automatically revert to flash sync speed when the shot is taken if a built-in or hotshoe-mounted flash is turned on. Usually this results in overexposure (unless you have a “safety shift” custom function enabled). If you’re getting overexposed images when using flash outdoors, this is probably the reason. The image is not overexposed because of light from the flash. It’s overexposed from ambient light because the shutter speed was too slow. If you’re using flash for fill in bright situations, it’s necessary to stop down the aperture or lower the ISO setting to get the shutter speed below flash sync.
 
 
Hm… so…amacam, korang pening tak bace? aku agak2 la….hehe… Kalau ade pape idea nak tambah, nak tanye, nak bincang, just letak jek comment kat bwh tu yek…kalau aku tau, aku jawab, kalau aku pun tak tau, kite same2 la cari jawapan die….it is open for discussion as i myself also still in the learning process…. To be continued for FLASH part2, part 3 and part 4… :p….