Canon DO Lenses??

[John Cloran]

I am wanting to purchase a Canon 400mm f4 and notice that all the adds use the term DO in the full lens description. What is the difference between these lenses (DO) and other L Canon lenses if any?

Thanks in anticipation

[Manfred M]

Hi John - welcome to CiC.

DO means that one of the lens elements is a fresnel lens (DO stands or diffractive optics). What this means is that by using the optical principle of using a series of tiny concentric angled lines results in having a relatively thin optical component can replace a piece of thick curved glass.

https://en.wikipedia.org/wiki/Fresnel_lens

As an end user, this means you get a smaller and lighter lens. So far as I know both Canon and Nikon use this type of optical element in some of their latest lens designs.

[John Cloran]

Hi John - welcome to CiC.

DO means that one of the lens elements is a fresnel lens (DO stands or diffractive optics). What this means is that by using the optical principle of using a series of tiny concentric angled lines results in having a relatively thin optical component can replace a piece of thick curved glass.

https://en.wikipedia.org/wiki/Fresnel_lens

As an end user, this means you get a smaller and lighter lens. So far as I know both Canon and Nikon use this type of optical element in some of their latest lens designs.

[John Cloran]

Many thanks for the prompt response. Your bottom line being as an end user it makes it possible to have a smaller lighter lens makes sense, much appreciated.

[Saorsa]

Hi John - welcome to CiC.

DO means that one of the lens elements is a fresnel lens (DO stands or diffractive optics). What this means is that by using the optical principle of using a series of tiny concentric angled lines results in having a relatively thin optical component can replace a piece of thick curved glass.

https://en.wikipedia.org/wiki/Fresnel_lens

As an end user, this means you get a smaller and lighter lens. So far as I know both Canon and Nikon use this type of optical element in some of their latest lens designs.

Nikon refers to theirs as PF lenses with PF meaning Phase Fresnel.

[loosecanon]

Unfortunately the two early models using the diffractive optics by Canon - a 70-300 zoom and the 400mm prime both suffered from a problem with out of focus highlights, in much the same way as mirror lenses do. The latest version of the 400mm has changed the optical configuration to reduce this problem.

[William W]

. . . What is the difference between these lenses (DO) and other L Canon lenses if any?

For clarity a small, but maybe important point:

At this time, none of the three Canon "DO" Lenses, (EF 400 F/4 DO IS USM; EF 400 F/4 DO IS MkII USM; EF 70 to 300 F/4.5~5.6 DO IS USM), is an "L Series" Lens.

DO Lenses sport a GREEN Band: L Series sport a RED Band.

*

If you want an L Series 400mm lens, then I am almost certain there are 5 (five) of those lenses in the EF range and none is an F/4 Lens. Obviously not all are current models:

400/2.8L; 400/2.8L MkII; 400/5.6L; 400/2.8L IS; 400/2.8L IS MkII

WW