Diffractive Optic Lenses

[2new]

A few quick questions;

With the introduction of the new 70-300mm DO lens, are there currently only 2 Diffractive Optic lenses offered by canon?

Does anyone have 1st hand experience with the DO lenses?

[or can you point me towards some reviews on a Canon-DO lens?]

L- Glass quality or better?

Thanks

[CyberDyneSystems]

Indeed there are only the two, (Well one so far,. the 400mm f/4 DO)

The talk about the 400mm f/4 DO is that the cvast majority of serious photographers that have owned it fell it is the "softest" of the Canon 400mm lenses. By sacrificing a stop and saving $3,500.00 you get clearer sharper pics with the 400mm f/5.6

This is all based solely on things I have read.
But the general consensus is that the 400mm DO was overpriced, and not as high quality an image when compared to other L prime telephotos.

[CyberDyneSystems]

On another note,. the concept that DO lenses use looks similar to some of the lighting instrumnets we use in the theatre,. the "Fresnel" has the same sort of rings cut into the lens do get an enhanced even dispersal of light over a broad area. (reduces the "hotspot")

Interestingly,. one of the hallarks of the fresnel is the light has a pleasing "softness" to it that makes it preferable to other lighting instruments under certain conditions.

[Canuck]

On another note,. the concept that DO lenses use looks similar to some of the lighting instrumnets we use in the theatre,. the "Fresnel" has the same sort of rings cut into the lens do get an enhanced even dispersal of light over a broad area. (reduces the "hotspot")

Interestingly,. one of the hallarks of the fresnel is the light has a pleasing "softness" to it that makes it preferable to other lighting instruments under certain conditions.

CDS,
You are bring back some memories of high school like '95-'97 in particular.
I was a part of the lighting and sound in Bye Bye Birdie, Up the Down Staircase, and Annie that we did. I am very familiar with all that stuff. We had a follow spot that was much like the one you mentioned in another post that is could set paper alight at 10 metres. Good times. I have to go check something out, next time I am back home. I asked about this one. We were good friends anyway but I first as I asked for a permanent marker. Then I asked about making some graffitti, so to speak. He asked for clarification. I replied that I was just gonna sign my name and date it. He walked away and was like I leave it to you to do whatever. I signed it and dated it 16th Mar 1997. I wonder if it is still there? That will be a question I have for next time. Man those were fun times. I must say that was some of the most fun I had my junior and senior year. I have a ton of stories but that isn't for here.

Back to the photog stuff, do you have problems with wahing out colour w/ those monster follow spots? I would guess you might go an f-stop or 2 under what is reccommends, right? Just wondering.

[Jesper]

If you have a look at Canon's words about the new EF 70-300 mm DO IS USM (http://www.dpreview.com/news/0401/04012902canon70300do.asp):

"Full time manual focusing, a circular aperture diaphragm, and a zoom ring lock mechanism to fix the lens at the shortest focal length are all built in. The lens boasts image quality approximating that of Canon's L series professional lenses. It is likely to appeal to professional photojournalists and serious advanced amateurs with a need to contain the size and weight of equipment carried."

I hope it does approximate L quality, because this lens looks great: such a small, light and inconspicuos zoom that goes all the way to 300mm. I wonder how the image quality compares to those big white zooms. I'd much rather have this new lens than a big white one, because it would be so much easier to carry and it doesn't attract attention. I'll just have to wait a few months until it's available and someone will test it... in the mean time, I'll start saving money...

It's also nice that Canon learned from the past and added a zoom lock button to prevent the lens from sliding out when it's hanging down - this is a well-known problem with the 28-135 IS USM (which I have).