I'm sure this question has been asked and debated, but I'm a new photographer (5 months in) and currently am shooting with a Rebel XT and a 17-40 L. The L Glass is amazing. Beautiful quality.

I'm looking towards doing more Portrituare / Fashion stuff as well and am looking for a lense for this.

I don't want to spend the 2 grand on the 70-200 2.8 IS, although I'd love it (wouldn't we all!). I'm thinking of the 70-200 F4 for 650.00 to start. Would anyone have any pro/cons, opinions about this lense. Any compelling reason why I should spend twice as much to get the extra stop.

I'm looking at down a mixture of dimmer light, as well as outdoor photography. I love naturual light and have a tendancy to not flash a lot.

I appreciate all your help, L-Series are addictive.

Shane

Have you considered the Sigma 70-200 f/2.8? You would get the extra stop for similar price.

Thanks for the reply. I haven't tried any Sigma lenses, as I always have heard the L glass is the best. I started on a Nikon 8800, which is an amazing camera, but I upgraded to the Rebel a few weeks ago, the Nikons quality was great. Most of the pictures on my blog are from it, http://www.shanejmontgomery.com. The L-Series has something I can't put my finger on, it's just a level of contrast and clarity I never saw with the Nikon. To correct myself, I don't know if this is the L glass or just the fact it's an SLR camera.

I think the best thing to do is take advantage of this shop by my house which lets you snap shots from any lense and compare side by side the sigma and canon.

I've also thought about the 85mm 1.8 L series, but kind of what some leverage of zoom at this point since I'm such a beginner.

Trust me, I understand the draw of the L's , I was just thinking for the viewpoint funtionality and whatnot. To me, the use of the extra stop would out weigh any shapness differences. Also, keep in mind that you can stop the 2.8 down to f/4 to better the sharpeness, whereas the L f/4 would be wide open.

I'm not sure how coherent that last sentance was, but I think you know what I mean.

I've seen shots from the Sigma and the Canon, and they are comparable, it's one of their better regarded lenses.

Although, the L is nice and small...

Nice photo blog by the way, I love "Pizza".

Thanks man, your advice is helpful. It sounds lame, but I actually didn't know aperture had any bearing on sharpness or detail. I thought it was just light. My girlfriend mentioned that it indeed did. I have so much learning to do!

You can't go wrong with a EF 50mm+85mm 1.8 combo for portraiture/fashion on your camera, if you buy second hand then you will have plenty money left for some decent books or a studio light and reflector. The 70-200 f4L lens is a great lens but if you are looking for portraiture I wouldn't advise it as a starter lens.

That's actually a very compelling argument for the f/2.8L IS. The extra stop comes in very handy in low light and makes the viewfinder brighter, and IS increases handholdability an additional 2-3 stops. For subjects that aren't moving quickly, you have a 3-4 stop net advantage over the f/4L, and for things moving too quickly for IS to help, you still have a minimum 1-stop advantage. The IS is also very handy when shooting from a tripod; it dampens out vibrations from mirror slap and wind, and makes shots possible that would otherwise not be; the 3-4 stop advantage comes in to play there as well. That makes the 70-200/2.8L IS well worth its extra cost IMO. And optical quality is excellent.

Primes are fine in a studio environment where you have all the time and space you need to set up the camera and lighting for each shot, but for dynamic environments like a fashion show where you may have to shoot from a single assigned location and quickly switch from a head/shoulder closeup to a full-length shot, a good-quality zoom can be a lifesaver. If you need a 200mm lens for the right framing, a shot from any of the 70-200L zooms at 200mm will beat a crop from the excellent 135/2L prime hands down.

Another thing to keep in mind is the issue of depth of field.

If you do portraiture and fashion, you probably want the background to be out of focus, most of the time.

A wider aperture gives you this opportunity, while with an f/4 lens, you may have problems making it work. I say "may", because it's a matter of distance to your subject and the distance to the background.

This is where the fixed focal length lenses such as the 85mm f/1.8, 135mm f/2 and 200mm f/1.8 (sigh, sigh, sigh, give it back, Canon, give it back!) shine.

This isn't meant as a rebuttal to Jonathan at any level, it's just a few more things to consider in addition to what he wrote.

>> I'm sure this question has been asked and debated, but I'm a new photographer

Somehow I fail to understand what is the relevance of your photography experience to your search skills.

I find the 70-200 F4 to be a great travel lens. If money were no object and the lens will not have to be carried a long ways the 70-2002.8 IS is sweet.

Forgot to add a few links to get you going.

http://www.photozone.de/8Reviews/index.html

http://www.photo.net/canon/70-200

http://photonotes.org/articles/beginner-fa...html#telephotos

Just that I am a beginner and therefore wanted to do some investigated on how to best accomplish my goals prior to spending 2000 dollars on a lens I chose the f/4, and am extremely happy with it though. Thank you all for your help. Perhaps when I graduate to doing studio shots and portraits I'll sell this and grab the 2.8

it probably doesnt apply, but i find a 2.8 to be invaluable to my photojournalism work.