I need some help

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Hello there :) I really have two questions for you tonight. The first one is, I am looking to buy a flash for my rebel 2000. I am looking at the 220ex and the 380ex. I was wondering if you could tell me if the 220ex has a zoom head on it. I would like something better than my pop-up flash, but also needs something that will go the distance when I am using my 100-300 lense for close up pictues in a some what low light situation. Can you please help me?? My second question is, when something says it is 100mm, how can you turn that into feet?? I read it somewhere and do not remember where I saw it at. I would like to know this so I will know who many feet my flash will go. And also so I can figure it out for my self in the future when I go to by a new lense. Thank you for taking the time to read my questions. I hope I didn't confuse you with the way I typed the questions. I look forward to hearing from you.

-- Debbie Gampolo (gampolo@webtv.net), October 08, 2000

Answers

Debbie: It is my firm belief that one should strive for a hotshoe flash that first-and-foremost features a flash "head" which both tilts AND swivels, because this allows for "bouncing" the flash's light output in both horizontal and vertical compositions while the flash remains mounted on the camera's hotshoe. Therefore, the new EOS 420EX flash may be your best bet, although I don't know if this flash has actually been released onto the market yet.

To learn more about "guide numbers" of electronic flashes, click on the "Learn" section of Photo.net, find the discussion on flashes, and you'll find some useful information. Best regards.

-- kurt heintzelman (heintzelman.1@osu.edu), October 08, 2000.


To expand on Kurt's answer; the 380EX's head zoms and tilts, but does not swivel, so you are somewhat limited while bouncing flash. Mostly limited while in a vetical shooting format. The 220EX doesn't tilt or zoom, and as I recall, it doesn't zoom either.

As Kurt said, tilt & swivel are much more important than a zoom head. Especially while shooting closeups. The zoom feature will allow you to get farther away from your subject and still properly expose it, but you don't need a zoom head for a long lens, only for long distances.

Either of these will do what you want it to, as well as mimick tilt & swivel, if you attach it to your camera with Canon's Off Camera Shoe Cord 2 and mount it on a flip type bracket. The 380EX has more power as well as more features.

-- Jim Strutz (jimstrutz@juno.com), October 08, 2000.


Debbie,

I have the 380EX which I use on the ElanIIe. I am very pleased with this flash. I don't know anything about the 220EX except that it's not as powerful as the 380EX. However, one thing I have learned is that if you are deciding between two flashes, it's always better to go with the more advanced one if you can at all afford it. I did that regarding the EX flashes you mentioned as well as the Vivitar flashes I own and can see, in retrospect, that I would've quickly outgrown the smaller, cheaper flash units. If you can afford the 420EX or 550EX all the better. The more advanced flash will give you good results and offer features you can "grow into" as you progress.

Your second question is probable referring to the Guide Number system. A guide number is an expression of the power of the flash. I find an understanding of the Guide Number system very useful. Using simple formulas, you can determine the effective range (often called working distance ) of your flash, determine what aperture to use in Manual flash mode and so on.

It's not complicated, but keep in mind that your flash's power,as well as your film speed, lens aperture and focal length ALL effect your Guide Number--and therefore your calculations.

Check your flash manual for a guide number table. Be aware in ads and brochures they are often overstated, by referring to the number at a telephoto focal length.

Here's a website that offers several short clear explanations, along with other info regarding flash:

http://www.chem.helsinki.fi/~toomas/photo/flash-faq.html

Good luck! Roy

-- Roy Kekewich (roykekewich@yahoo.com), October 09, 2000.


Oh yeah, the conversion from meters to feet. There are 39.37 inches to a meter, as I recall, so if you multiply meters by 3 you get something close to feet (you have to add about 10% to get it closer to being right). Also, there are about 25 mm per inch. So if you divide your hypothetical 100mm by 25 you end up with about 4 inches. This last conversion is of limited use in modern photography since even in the USA we stopped using inches to describe lens length.

As far as guide numbers for flash, you might see something like this; GN 42 meters (138 feet) @ 100 ISO on the new 420EX. All that means is if you were using 100 ISO film with an f:1.0 lens (You don't have one of those, and nobody I know does either) you could shoot with flash as far as 138' (42 meters). Since you are more apt to be shooting with an f:4 lens (2 stops slower), you can only get out to 69' (21 meters). At f:8 you would be limited to 34'. You can gain 2 stops back (and the distance) if you switch to 400 ISO film.

The 220EX has a bit more than half that power (22 meters) but is still adequate for most uses. The problem with it is it's crippled without the features that you probably want.

-- Jim Strutz (jimstrutz@juno.com), October 09, 2000.


Pretty good answers. I just felt the need to mention that there is a 4 stop difference between f1.0, and f4.0 - 1.0, 1.4, 2.0, 2.8, 4.0, in full stops. It is an easy mistake to make, but you multiply by approximately 1.4 to get the next smaller f stop, not 2.

By the way, I use the 380EX, but the 220EX isn't really the slouch it seems like. The guide number rating of 22 meters covers the angle of a 28mm lens, which is only 1 meter less than the 380EX at the 28mm zoom position. The power of the 380EX and the other zoom flashes is deceptive because they are rated at maximum zoom. To find the guide number of a Canon flash, just drop the 0 from the end of the number, and you have the guide number in meters. Multiply that by 3.3 to get a close approximation of the guide number in feet. Also keep in mind that using a 220EX will be fine with a long lens, but it won't cover the full angle of view if you have a 24mm or wider lens. The 380EX can cover a 24mm lens, the 550EX can cover as wide as 17mm.

-- Brad Hutcheson (bhutcheson@iname.com), October 09, 2000.



So the 220EX will be great if you always use a 28mm lens...

The 380EX has a guide # of 102 at 50mm and it's only $30 more at B&H. IMHO zoom & tilt for that price make it an easy choice. Sigma recently announced a new flash that uses E-TTL, does tilt & swivel, and has full manual control. 550EX functionality at what is bound to be a much lower price.

Even with a 550EX I wish I had more power when doing bounce, which is almost the only type of flash I do.

-- Steven Fisher (srf@srf.com), October 09, 2000.


"Pretty good answers. I just felt the need to mention that there is a 4 stop difference between f1.0, and f4.0"

Well, that's what I get for thinking when tired. Just divide all my distance calculation in two.

-- Jim Strutz (jimstrutz@juno.com), October 09, 2000.


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