What happened to the "flare-cut diaphragm"?

[JumboShrimp]

The current Canon EF 28/1.8 has what Canon calls a "flare-cut diaphragm" (or something like that). It is visible in most product shots of that lens. I also believe that the long-discontinued Canon EF 28-80/2.8-4 L had one of these retro-installed after complaints were received about its tendency to flare. To the best of my knowledge, no other Canon SLR lens has such a thing. Anyone know why? Seems like a good idea ...

You can see the 28/1.8 product shot here from B&H: http://www.bhphotovideo.com/c/product/102851-USA/Canon_2510A003_Wide_Angle_EF_28mm.html

 

[Coldhands]

They were probably rendered obsolete by advancements in lens coatings as well as computer-aided lens design. I think a version of Nikon's 18-55 kit lens has one but otherwise they seem to only exist in older designs.

 

[msowsun]

Interesting.... I found this online: http://www.mir.com.my/rb/photography/hardwares/classics/eos/EF-lenses/EF28mmf18USM/index1.htm

"Optically, it has an aspherical element placed as its 6th element, this has reduced the number of possible additional glass elements in its optical design and keep the lens size down as well as reducing spherical aberration to minimal level. A flare cut diaphragm is actually installed behind group one that helps to improve contrast even when backlit scene shooting is required"

Also...

A flare-cut diaphragm installed behind group 1 blocks unwanted light to ensure highest contrast.


The EF 20-35mm USM also has it. http://mir.com.my/rb/photography/hardwares/classics/eos/EF-lenses/EF2035mmf3545USM/index.htm

The front section of the lens has a mechanism which is actually a flare cutting diaphragm (see picture at left) designed for shielding bright light source at corners.

 

[Cinto]

http://homepage.eircom.net/~edwardtim/photo/canonFAQ.html#3Q5c
Has a list of lenses with flare-cut diaphragms. Some current lenses on there are the 17-40L, 135L and the 180L macro.