Patent: New Diffractive Optic Patents

[tron]

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As both Tokina and Sigma claimed inability to update their old lenses to work with digital Canon bodies I do not trust them any more. This can happen again.
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I am new to this. When did this happen?

I bought the Tokina ATX28-70 f2.8 by the year 1993. It worked fine on my EOS600 and EOS620 (and later I found out that it worked fine on EOS1n). When I tried to use it on a EOS50E (1996 or 1997) the camera was blacking out when I pressed the shutter release. Needless to say it does not work with digital bodies too

My old Sigma 14mm - I say old because there was a newer edition of that lens - works ... a little on my EOS5DmkII Only when the aperture is fully open (You can only imagine the vignetting I get! I didn't even care to check the optical quality).

I didn't even know that there was at least a specific usable aperture until I saw at ebay a listing of a very old SIGMA 500mm that was reported to work with analog bodies plus with EOS5DmkII at open aperture (only). That gave me the idea to check my SIGMA lens.

Check:
http://www.ebay.co.uk/itm/Canon-EOS-Sigma-APO-500mm-1-4-5-Case-/170784321711?pt=UK_Lenses_Filters_Lenses&hash=item27c389f0af

"This lens will only focus on digital cameras like the 5D or 50D and work with an open aperture, you will get an error message if you stop down "

 

[Renato]

I sure hope that this does not intensify in the future. I need the lens, I dont have the money so I buy other brands. I imagine that that the same type of problems have happened to other manufacturers.

 

[tron]

I sure hope that this does not intensify in the future. I need the lens, I dont have the money so I buy other brands. I imagine that that the same type of problems have happened to other manufacturers.

What bothers me most is the attitude of the 3rd party manufacturers. They are not interested to rectify these problems (they did not even offer a part exchange towards a working model). So I feel they deserve even more to be 'punished". As far as Canon big white equipment is concerned I will try to find something used when I needed and assuming the price is reasonable. I am an amateur so it is not the end of the world if I don't get an extreme telephoto lens.