Copying lenses

[tim]

Is there anything stopping smaller lens manufacturers taking a lens from a big manufacturer (Canon/Leica/etc), reverse engineering it, replicating the elements and design, and selling it? And if not, has it been done already? Seems like a cheap way around investing in R&D.

[felix21685]

i read somewhere a letter or email that canon wrote and thats what they said is
that i believe they were mentioning sigma ..does..they take apart canon lenses and and reverse engineer them.
i wish i remembered where i saw this..dont know if it was real ..but it seems to make sense u know..

[Ikinaa]

That's exactly what Sigma and other do...

http://photonotes.org/reviews/sigma-ef-500-super/

[tim]

I know Sigma reverse engineers the lenses and cameras to work out protocols, but do they copy the optical design too, or just the electrical?

[buze]

I don't think they copy the optics, they have a bunch of lens with no Canon direct equivalent after all. They adapt to the protocol, and they might learn something of the manufacturing in the process, but I don't think it's easy to xerox a piece of glass :D
Beside, I hope Canon reverse engineer the manufacturing process of Sigma too, some of their lens are really well made :D

[Cadwell]

Sigma (and others) reverse engineer the Canon lens mount and lens / camera communications protocols - be grateful that they do, otherwise there would be no competition / alternatives to the Canon product and hence the Canon prices would be even higher than they are - as Canon refuses to "license" the protocols.

They don't reverse engineer the lens optics / focus mechanisms / IS mechanisms. These are Sigma / Tamron / Tokina designs.

[ed2day]

My impression is that with CAD technology the optical design isn't that big of a deal. Most the technology in a lens has been around for at least 50 yrs. It really come down to process technology-- not just putting the thing together, but coating deposition, miniaturization while holding tolerances etc. Those are not easily reverse engineered.

The reason they don't come out with exact knockoffs of Canon lens is economics--they come out with a generic type design and adapt it to work with Canon, Nikon, and whoever else.