Absolutely! 300mm is a real sweet spot for the zoom. A rival to the ultra lightweight Nikon 300mm f/4E PF would be nice but the versatile 100-400 is just so good with IQ and AF I’d never buy the prime.It needs an update (won't happen though, at least not EF). My copy of the 100-400 ii is sharper at 300 mm than my copy of the 300. My 300 just sits on the shelf since I bought the 100-400.
I was thinking the same thing, Canon newer actually released the updated 400mm and 600mm DO they were showing at the Canon Expo a few years back.A DO element you mean
I'm actually curious if they just abandoned that tech or if we'll see more of it once the big whites are moving to RF.
The Nikon uses a classical Fresnel lens which uses refraction. Canon has its concentric rings of the separation of wavelength of light and is diffractive.Seems that high ISOs, IS and a market demand for zooms make a 100-400 or ___-300 f5.6 more worthy of development investment than a 300 f4.
My research suggests that the Canon DO system is arguably a misnomer. They are what I would call encapsulated or immersion fresnel lens elements. They appear to rely on refraction by concentric lens elements that are orders of magnitude larger than the wavelength of light. They are for the purpose of reducing chromatic aberration in the manner of an achromatic lens with a second element of a different optical index. Except that element is formed using fresnel shapes molded on conventional lenses in thick coatings that are orders of magnitude greater that the wavelength of light. The rays are beneficially affected by the structure only by refraction, not diffraction.
That’s as best as I understand from the internet and Canon’s marketing. I should look for a patent and welcome any illumination. Also help understanding distinctions from Nikon’s system.
That’s what I expected but it seems inconsistent with Canon’s marketing images. My initial research found no use of diffractive optics for conventional imaging.The Nikon uses a classical Fresnel lens which uses refraction. Canon has its concentric rings of the separation of wavelength of light and is diffractive.
In practice there are very few, if any, reports of problems with highlights. The same is true with the 400mm DO II. These lenses are most frequently used by birders and nature photographers who are not photographing bright lights. Neither the Canon or Nikon offerings are at their best with backlit objects, however. I have never personally come across problems apart from loss of contrast with back lighting with the DO II.The trouble with the Nikon lens, according to Optical Limits, is it's rendering of highlights (halos etc...).
200 µ is in the region of the grating pitch for a Fresnel diffraction lens. You can buy one cheaply from here https://www.aliexpress.com/item/1705307240.html to satisfy your curiosity. These are planar sheets of plastic without curvature for refraction.I'm researching, and this Canon patent publication is helpful. It has a grating pitch of 200 micrometers (about 400 wavelengths) It says diffraction, but I still don't understand how the majority of all rays could be "diffracted" to generate an image. If feels like a refractive system in which diffraction at the edges of the facets is an undesirable artifact to be minimized.
This Canon article has a lot of what might be described as "marketing hand-waving." it's entirely consistent with my initial take that the imaged rays are refracted, and the purpose of the advanced concept is to minimize undesirable diffracted rays. My sense is that marketing wanted to do everything they could to avoid the word "fresnel" as a poisonous (though technically accurate?) poison.
This image showing the fresnel rings makes my point. The imaging rays are passing through the facets, and diffraction at the transition lines is to be minimized.
My current conclusion is that this report is simply not true, except that Canon avoided the "fresnel" term (presumably for marketing reasons)."Canon never uses words ‘Fresnel element’ but they call their technology ‘Diffractive Optics’. It is in full accordance with the actual state of things. The height and pitch of concentric grating in the shape of optical elements showed in Canon diagrams have indeed the same size as the wavelength of falling light. As a result you deal not with refraction but diffraction. That’s why the official Canon materials never employ a term ‘Fresnel element’, only ‘Diffractive Optics’.