100-400mm f/4.5-5.6; Canon vs Sigma

[washer]

I am on the market for a telephoto for my Rebel XT in the 400mm range. I have pretty much narrowed it down to 2, a Canon and a Sigma. Both Zoom Telephoto and f/4.5-5.6. The Sigma is $400 chaper than the Canon. What is the advantage of the Canon? Just the name brand? Is there a reason I should opt for the Canon? This is a birthday present. My teacher has the Sigma and loves it. He pretty much sold me on it, I'm just doing a little more research before I commit. Here are the B&H links:

Canon Zoom Telephoto EF 100-400mm f/4.5-5.6L IS (Image Stabilizer) USM Autofocus Lens
http://www.bhphotovideo.com/bnh/con...s&Q=&sku=162616&is=USA&addedTroughType=search

Sigma Zoom Telephoto 80-400mm f/4.5-5.6 EX DG APO OS (Optical Stabilizer) Autofocus Lens for Canon EOS
http://www.bhphotovideo.com/bnh/con...s&Q=&sku=389504&is=REG&addedTroughType=search

anybody have any advice? I guess I am leaning towards the Sigma right now. I am a senior in high school and have really gotten into digital photography with my Rebel and digital art classes (im a TA with said teacher this year) in the past two years.
Thanks a ton
washer

 

[Abstract]

Can you borrow it and take some photos with it?

If you like the photos you get with it when testing it out, then buy it. If not, then don't. I think that's the best way. Listening to a bunch of people at a forum, who will all likely suggest the Canon anyway, isn't always the best thing to do. If you're happy with the photos, then the Sigma is what you should get since it's cheaper.

 

[washer]

sweet. thanks abstract, the sigma it is.
i just get nervous before big purchases like this and like a little confromation/encouragement whenever possible.

 

[Clix Pix]

Is the Digital Rebel sturdy enough to handle a lens of this size and weight?

 

[washer]

oh yea, my teacher got an XT a few months after I did (he used to shoot film) and he loves it. He has a bogen monopod, but it holds up just fine. hopefully we are going to get press passes to a Wake Forest football game this season. and hopefully i will have some more glass to shoot with by then

 

[snap58]

Is the Digital Rebel sturdy enough to handle a lens of this size and weight?

If the lens / camera is held correctly, the lightness of the rebel should put less strain on it than the heavier Series 1 bodies. I have seen rebels attached to 600 mm monsters.

I think the point to make is that these come with a tripod mount for a reason, and you do not want to let any long heavy lens cantilever off your camera no matter what type or make it is. In addition to the strain on the mount the force developed by the moment arm would make it very awkward (and painful) to hold unless you had a grip like a gorilla. Also you do not run around with this combo hanging off a neck strap. : )

With a large / heavy lens, the lens supports the camera.

I am pretty sure you have never handled a camera / long lens that way, have you?

 

[wesjr]

I really like the Canon 100- 400 IS. It's the most versatile lens that I've ever owned. It works very well for close ups.

Here's a flower photo from this year using a Canon 5D.


http://att.macrumors.com/attachment.php?attachmentid=57745&stc=1&d=1158501141
dayliilyyellow6-03.jpg

 

[Clix Pix]

If the lens / camera is held correctly, the lightness of the rebel should put less strain on it than the heavier Series 1 bodies. I have seen rebels attached to 600 mm monsters.

OK, good, just checking.... I've seen so many comments about how small and plasticky the Digital Rebel is that I just wondered about its sturdiness when handling long and heavy lenses. If the lens mount is metal that helps, too. Thing is, a lot of Digital Rebel users may not be fully informed about proper lens handling.

Yes, you make a very good point about how the camera/lens is handled, and certainly I've seen the way some people hand-hold a lens..... A lens needs to be supported by one hand supporting it from underneath, NOT with the hand positioned on top of the lens! And, yes, the user should NEVER just let any lens, never mind a long, heavy lens, dangle off their camera body via a neckstrap! It is not a necklace!

Yes, for mounting on a tripod or monopod, that tripod collar is there to balance the lens safely and comfortably.

Although I use a neckstrap, regardless of which lens I have on my camera body, I always have a firm grip on the entire thing, supporting it with my hand and arm, never allowing anything to dangle....

Yes, when you get into long, heavy lens territory, indeed the lens supports the camera body rather than the other way around!