It is both the "L" and the larger aperture that contribute to the cost. The "L" stands for low dispersion glass. When light passes from one medium to another it diffracts or spreads out the wavelengths of light (in other words it creates a rainbow). This leads to a problem for photographers called chromatic aberration which shows up as color fringes in a picture and is more prominent as you get away from the center of an image. Better lenses use low dispersion glass which has a lower refractive index and consequently less chromatic aberration. Lenses use internal elements to try to correct the dispersion problem but higher quality glass requires less of a correction and thus, ultimately, leads to superior image quality.
Also, the larger aperture (particularly a 2.8) needs a very large lens physically to accommodate such a large aperture and a lot of glass leads to a lot of cost (not to mention considerable weight). By the way, even a lens with low dispersion glass can be mediocre. The type of glass merely means better quality materials - not necessarily better engineering. For what it's worth the 70-200 f/2.8 L IS lens from Canon is considered one of their best lenses. You might want to check out the review from the following link: https://www.luminous-landscape.com/reviews/lenses/70-200is.shtml Hope some of this helps you out..
Hey Mr. Pollack, Thank you very much for the lesson. That was exactly what my beginner brain was looking for. Thanks for the link also. I have one question and I know the answer will be biased but I have to ask. I just purchased the 20D Canon for myself.
My kids are graduating from HS over the next two years so I thought I needed a good Digital Camera to record all the sports and important moments. My wife kinda freaked when I told her how much Ipaid for the camera and lense combo. I now cannot go to her asking for another grand or 1500 dollars for this lense I absolutely have to have in order to take these kid pics I bought the camera for in the first place. Can you suggest a Canon lens for less than 1,000 dollars that will give me zoom out say 2 or 300. Fast auto zoom capability and will be mostly shooting sporting events.
Is it safe to say that all Canon lenses with the prefix EF will fit my camera? Thank you very much for letting me spill my thoughts to you. I hope you have a good weekend. Sid..
What quality of lens (or camera for that matter) is best is largely dependent on what the end use will be. If you only plan to have computer slide shows of your pictures then the best cameras and lenses irrespective of cost will be wasted since the output would fall far below the qualifications of the equipment. On the other hand if you intend on displaying mural size posters in the Museum of Fine Arts then it's likely that even the smallest differences will stand out. Beyond this everyone has their own perception of what is considered acceptable even with the same equipment. I'd suggest that you try posting your inquiry on the Canon 20D site within these forums. You can get to it from the main forum page by going to digital cameras - canon - Canon EOS 20D Digital SLR.
I wish I could give you the magic bullet you want and save you the trouble of doing more research but it's really better that you hear what many people have to say and then draw your own conclusions. I hope this helps. Joel..
Any Canon EF or EF-s lens (or any new third party "EOS compatible" lens) will fit the 20D. Guillermo..
I purchased the EF75-300MM F4-5.6 IS lens and used it in Europe this past summer for several weeks.
I also used the EF S17-85 mm F/4-4.6 IS USM lens Both lenses performed very wll and produced great pictures, unfortunately I did not have a flash attachment and some of the pictures would have been better with a flash, I purchased the speedlite 580EX. With the bove lenses and flash the pictures have been great..
Actually, the "L" (according to Canon) means "Luxury" and their prices reflect that designation They do contain low dispersion glass which is probably why many think the "L" stands for the type of glass.....the "L" is to distinguis between their consumer grade lenses and the "professional" line........
While I know that Canon's EF Lens Work III book indicates that the "L" designation is for luxury I still admit to being somewhat dubious about this claim since nowhere in Canon's descriptions about the "L" lenses is there any mention of this term. It seems to me that the term "luxury" was applied later as a marketing designation. If you check out the following link you will see that all Canon refers to in their description of the "L" lenses are the materials and build quality. If "L" meant luxury then it is also somewhat curious that Canon's DO lenses don't get that designation since they definitely are luxuriously expensive - instead they get the green stripe as opposed to the red. Anyway, as I said you certainly could be right and it's simply my cynical nature showing through. Joel http://opd.usa.canon.com/eflenses/technology/lseries.html..
Hi On canon lens the L is for professional.If you go on to www.canonusa.com you will find out what you need to know about each lens they sell...
Actually, "L" and the red ring denote lenses with fluorite elements, as "DO" and the green ring denote a lenses with diffractive optics. Usually those lenses are of proffesional build quality, and very good optically (at least, the L ones, DO ones varies), but some lenses don't need fluorite elements, as some primes, so despite being of proffesional quality (as the 50/1.4 prime for example) it doesn't have a L designation. Guillermo..