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Old Aug 1, 2005, 4:58 PM   #1
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I have had a lot of problems in the gym with taking picture because the lighting is never bright enough to freeze action of a basketball game or of a gymnast flying through the air. I am a senior in high school so money is a definate issue however I would basically just like a flash that will "do the job". I have a Canon Digital Rebel if that really matters. What flashes would you recommend? Also in buying a flash what should I look for? I know NOTHING about external flash so any information would be much appreciated. Thanks in advance!

Jeff Riederer

www.natimage.com


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Old Aug 1, 2005, 10:22 PM   #2
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j_riederer wrote:
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I have a Canon Digital Rebel if that really matters.
sure it matters, if you are buying tires, it's good to know on which car it will go :G

j_riederer wrote:
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What flashes would you recommend? Also in buying a flash what should I look for? I know NOTHING about external flash so any information would be much appreciated.
1) There are 2 big families of flashes:
-Dedicated (to camera) which offer you "ttl" mode exposure and may be some other features (zoom, AF assist , etc …)
-Non dedicated flashes (generic) which usually offer you manual mode (you calculate your aperture (and you set speed) , often they may offer partial manual power setting corresponding to a given GN (guide number) , and also "auto" mode which will control itself the power corresponding to a given aperture matching the camera aperture.
2) You have to decide which kind of flash you want (dedicated or not) and then it's power represented by the guide number (GN) . (the GN is given often at a long zoom setting to have a big number)
With a max distance of the subject considered , and agiven focal length considered, you can determine what minimum GN you need on the flash.

In short, to make a rough guess, at what distance the subject will be and at what focal length you will shoot?


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Old Aug 1, 2005, 11:26 PM   #3
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Well you just gave me way more information than I ever knew. I've never used or even expierimented with an external flash so these may be very elementary questions considering I am a professional photographer. All my photos are outside so my flash is usually the sun. But what is ttl mode first of all? also i never even knew there was an aperature on the flash. What purpose does an aperature on the flash have? On the flash are there a bunch of different settings sort of like the different ones on the camera? I was always under the impression that you basically just put a flash ontop of the camera and go shoot away. I can't imagine I would be more than 20-35 feet away from my subject and thats at most. How far do flashes go? Also will the external flash drown out the picture like the onboard one will if it is used too close? or is that where the aperature comes into play. I'm actually surprised how little I know about external flashes because like i said I've never had to use one. The more info and literature I can get the better!


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Old Aug 2, 2005, 1:30 AM   #4
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Just a word of caution...

You may find that your flash will make you an unwelcomed guest in some sporting venues. A gymnast or basketball player can be easily distracted by a flash in their face at court level. I know it is done all the time, but you could quite easily be asked to stop shooting at the whim of an official.

This is why professional venues have radio controlled strobes high above the floor, which are triggered by transponders given to sanctioned photographers at events. This is also why photographers assigned to local events often have those monstrously fast (and expensive) lenses hanging off the end of their cameras, while they shoot at very high ISO. I've seen some very good shots of High-school basketball taken with existing light and a good lens.

That being said, if you are shooting a basketball game, unless you have very good seats, you'll find that most of the action will take place far beyond your estimate of 20-35 feet, so get the best flash you can afford. Of course, you could ask everyone to shoot from your side of the court and save a few dollars. :-)

I'm not trying to rain on your parade here. I would suggest you check with coaches or officials at your school and get their opinion.

Cheers,

Tom, on Point Pelee, Canada
http://tomoverton.myphotoalbum.com
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Old Aug 2, 2005, 1:44 AM   #5
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Dedicated TTL flash units are expensive for a given power. But they are easier to use and the metering is more accurate.

The better automatic units have multiple power settings. Within a given range and power setting you use a certain f-stop. It meters the light and cuts the flash off with a thyristor when enough has been reflected back to its sensor. For something like a basketball game you would probably leave it on a single setting that would reach as far as you need. The more powerful the flash the better because you get better depth of field if you can stop the lens down a little.

I got a relatively inexpensive Vivitar 285HV with a zoom head. The zoom lets you concentrate light when you are zoomed out. It will reach to around 80 feet with a decent lens. If you had to shoot only to 35 feet you could stop down a little and focus wouldn't be as critical. It is a bulky unit and you might not need that much range, but I think you would appreciate not having to shoot wide open.

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Old Aug 2, 2005, 9:05 AM   #6
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Hi again,

The vivitar 285HV is an excellent "generic flash" which can easily satisfy you, your subject is relatively close.
http://www.vivitar.com/Products/PDFs/Flash/285HV.pdf

But, in my opinion, since you are not that familiar to external flash, your best bet will be a dedicated flash which offer you TTL and plus. It's a good choice to let you concentrate on the shooting, not on the camera/flash settings .

http://www.steves-digicams.com/2003_.../300d_pg2.html
I am not familiar with Canon dedicated flashes; there are also Sigma brand offering Canon dedicated flash too (and less expensive than Canon flashes).

About TTL:
TTL means "Through the Lens", with a film camera, a TTL flash out put is measured via the lens by a sensor next to the film plane, and the camera cuts the flash output at the right moment. With a digital camera, it's a bit different, it often use a "preflash" to calibrate the flash output. Also, all TTL system are proprietary with one brand (make) and are not compatible between different brands (makes) , (not generic system)

By the way, there is a dictionary here:
http://www.steves-digicams.com/digi_dictionary.html#t

A useful guide about "Guide number":
http://www.shortcourses.com/how/guid...idenumbers.htm



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