Two days early, the press release details of the coming RF 1200mm f/8 L IS USM leaked, and there are a few pleasant surprises. First among them is that the lens weighs just a bit more the RF 600mm f/4 lens, which is already very light for that focal length. A person Digicame-Info believes was the author of the now-defunct Nokishita blog posted posted the press release detailing the specs.
The minimum focus distance (MFD) is 4.3m, also roughly the same as the 600mm f/4, which means its maximum magnification will be twice that of the smaller lens. Doing the math, this means that a human head would completely fill the frame at MFD.
Not noted on the release are the lens dimensions.
For those with a glutton for focal length, the 1200mm lens does take both the 1.4x and the 2x teleconverters, rendering as much as a 2400mm f/16 equivalent lens. Of course, the air column in front of that lens will chip away at sharpness. Stabilization becomes difficult at these focal lengths. At f/16, diffraction effects can rob an image of sharpness and detail.
With yesterday's leak of product images and the details from this release, it appears Canon is putting out EF-style optical tubes, without the extra RF ring featured on other white L lenses like the 100-500 and 70-200.
Optical stabilization is rated to 4 stops (one fewer than had with the RF 600mm f/4), but that stat had an asterisk affixed to it. It has the standard three IS modes, and Canon's most recent lens coatings.
With the weight being so similar, as well as the minimum focus distance being almost identical, one might suspect this was an RF 600mm f/4 dressed up with an attached teleconverter-like group of elements. The 1200 is to have two large fluorite elements, one Super UD element, and a single UD glass element. While the lens elements are listed and emphasized differently than was done with the release of the RF 600mm, a Canon Rumors forum member pointed out that it doesn't eliminate the possibility that the bigger end of the lens could be largely the same as the RF 600mm f/4.
The full release, complete with weasel words and footnotes, is rumored to be coming on Thursday the 24th.
RF1200mm F8 L IS USMはRF600mm F4と拡大光学系を組み合わせている？
My new portrait lens!
I guess it's a clever way to recycle 90% of the parts from existing optics
Sorry but I see it as much more exciting than that.;)
Jack
Im intrigued. But it does seem like a pair of niche lenses. They will have to be a lot sharper than their original 400/600 + TC combinations for anyone to want to give up that focal length flexibility. Are there really that many people complaining about the iq of the 600mm + 2x TC? You are really fighting atmospheric issues at that focal length anyway, unless you are shooting small birds at a short distance.
I can’t wait for someone to perform some comparative tests!
Jack
With custom "magnifier design" specifically made for the lens(es), the optical result should be (hopefully considerable?) better then using a "generic" 2x extender on the lens(es).
But I'm sure we will be seeing lots of practical comparisons telling us more about that...
2) Anyone who can afford the RF 1200 f/8 probably already has the other two
My spidey sense got tingly too. That's why I went and looked up the 600mm optical design. The elements list show it's not just a TC glued onto the RF 600. Had Canon considered doing that, I don't think they'd expect to sell many, as there doesn't seem to be a downside to just carrying the 2x TC with the 600. I'm betting there's something more useful than an extended 600 to this.
We'll just have to wait for 1) the full press release to come out, 2) Canon's chosen people to give reviews where they don't directly compare image quality between this and Canon's other big whites, and then 3) wait for the supply chain to unkink enough so that some of the forum dwellers are able to get some actual time with it. So, in other words, June :(.
It would make more sense for them so sell a 600 with a built-in 2x teleconverter unless people would be dumb enough to pay more for a 1200 f/8 that is no better than a 600 f/4 with a 2x teleconverter.
Having said that, I don't know how much improvement you could get when doing that and this is more about having fewer moving parts on a huge, heavy lens.
EF 800mm is 4.5kg or 9.9lbs.
Will it cost below $17,000?
now, for birders, they will have to decide whether they go for a 600mm f/4 plus 2x TC to be a bit more flexible or get the new 800mm. It'll also depend how well the latter one will work with TCs to get even more reach (and often catch more details of atmospheric blur :p)