It's not a myth, it's the truth based on the design of Canon and many other wide angle lenses. It's possible to design wide angles that are more "telecentric," which is what thost other designers have done, but it's the truth with regard to Canon lens designs.
Do you believe everything Canon says? Recall how they denied that the 1DsMKII was dropping images until there was no where they could hide, then they tried to "fix it" with firmware that didn't help? And they are still denying that the 70~200/2.8L USM IS has lock-up issues that continue to plague some earlier users. Remember when Canon came out with the 17~40/4L USM and Canon said it was designed especially for Full Frame digital cameras? Canon stated it was supposedly designed with a "special" rear element that collumated light broadly out of the rear for superior wide angle performance? Now Canon recommends the 17~40/4L USM be used only on small sensor cameras only. Hmmmm.
The Canon wides were poor performers with an EOS film body also.
"While this is an excellent ultra-wide zoom lens for analogue (film) SLR cameras, this lens is especially well suited for digital SLR cameras which usually have an imaging sensor size smaller than the 35mm format. When used with such digital SLR cameras these focal lengths can give an angle of view approximately equivalent to that of a 28-70mm lens used on a 35mm camera, which makes it the ideal standard zoom lens."
It sounds like you are reading into the B&H description that the 17-40 vignettes or is soft on the corners on a FF digital, when in reality, it doesn't state that at all. It does not say a thing about it's performance on FF digital.
Actually it plainly states that it is an excellent ultra wide angle zoom for film and is also well-suited as an ideal 28-70mm standard zoom lens for cropped sensors.
Contrary to your conclusion that this is a recommndatuon against the 17-40 on FF digital slr, it is more logical to conclude that, if it does not vignette on a film slr, and it is moreover excellent on a film slr, then most likely, it would still be acceptable on a FF digital.
There are also many FM users here who are pleased with the FF performance of the 17-40. Castleman and Luminous Lanscape review the 17-40 very favorably, even in compariosn to the doubly expensi e 16-35.
While I cannot comment on FF digital performance, it gave me spectacular results on my film slr; no vignetting and good sharpness throughout.
Anyway, where is the Canon statement/recommendation against using the 17-40 for FF?
jjlphoto stated:
Actually I read it here on the FM Forum. And also at:
"While this is an excellent ultra-wide zoom lens for analogue (film) SLR cameras, this lens is especially well suited for digital SLR cameras which usually have an imaging sensor size smaller than the 35mm format. When used with such digital SLR cameras these focal lengths can give an angle of view approximately equivalent to that of a 28-70mm lens used on a 35mm camera, which makes it the ideal standard zoom lens."
Steve_T90 wrote:
I find it ironic that Canon is now the manufacturer that is working to keep existing lenses from obsolescence. It wasn't that long ago that they were blasted by one rival that kept its lens mount the same during the AF revolution ("you'll be able to use the same lens you bought in 1959," etc), and now those rivals' new digitals have some major compatibility issues with 35mm lenses, not to mention that they all waste a huge portion of those lenses' image circles. If the "sweet spot" rhetoric was much more than mere spin, Canonians would all be mounting Hasselblad lenses on their 1DsII's, wouldn't they?...Show more →
Venus wrote:
What are they going to do with the thousands of angry 20D users if they dumped all the smaller sensors and only produce FF in future?? Many might jump ship and cross over to Nikon. Hopefully these guys at Canon wouldn't be so impetuous.
PParker wrote:
John, no offense taken. Maybe my assumption is incorrect thinking that wide angle performance would be improved with a slightly large sensor. I talking about a minimumally larger sensor that hopefully wouldn't require a new line of lenses.
The current lenses project a diameter of only 43mm, according to Canon's Lens Work III.
The old initial sample page got also a 17-40 sample pic. I've been reading a lot about this lens before I ordered it myself. Very good result on my 50.