AF not working with TAMRON lenses on R5C in video mode

[PeteAG]

Hi there,

I just bought the R5C and I am fairly dissapointed by the fact that the AF of my two TAMRON lenses (SP 35 1.4 and SP 70-200 G2) does not work in video mode. In photo mode everything is perfect but in video mode...no chance. The problem is broadly discussed at reddit, DPReview a.s.o.

Seems to be fixable by Canon cause these lenses DO work on a C70.

CANON, please fix this as soon as possible!

[deebatman316]

Canon is NOT REQUIRED to make THIRD PARTY lenses work with their gear. So its not up to Canon to make the lens work.

-Demetrius

40D, 5D Mark IV, EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 28-135mm F/3.5-5.6 IS USM, EF 50 F/1.8 STM

430EX III-RT & 600EX II-RT

[PeteAG]

So tell me why is it working on a C70 and a C300MII?

[deebatman316]

Tamron and Sigma have to reverse engineer the lens mount to get the electronics in the lens to work. Camera manufactures DO NOT release their proprietary lens communication protocols to other companies. You must've gotten lucky with your other cameras. Or Canon changed something in their lens communication protocol.

-Demetrius

40D, 5D Mark IV, EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 28-135mm F/3.5-5.6 IS USM, EF 50 F/1.8 STM

430EX III-RT & 600EX II-RT

[Tronhard]

Well... actually, reverse engineering is actually illegal.  OEM manufacturer allow IP to be available to 3rd party manufacturers under licensing agreements, for which they pay a fee.  That is why, up to this point, DSLRs and some MILCs (M-series) have 3rd party lenses that are available and work.  Canon have not, so far, allowed 3rd party manufacturers that license - which makes sense, given they are still developing their line of lenses, and want some return for that huge investment.  

If history repeats itself, for the EF-M series and the 1990's, Canon will have a few years of exclusivity, and then 3rd party lenses will become licensed and make lenses that work.   See my lengthy post on this HERE 

[deebatman316]

I guess I should've put it that Canon doesn't release their communication protocol. The 3rd party has to figure out how to make their lenses work for a particular mount. So Canon can not grantee compatibility with 3rd party items.

Edit: In some countries reverse engineering is legal. But patent infringement is illegal unless the patent has expired.

-Demetrius

40D, 5D Mark IV, EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 28-135mm F/3.5-5.6 IS USM, EF 50 F/1.8 STM

430EX III-RT & 600EX II-RT

[Tronhard]

I referred to an ex-client who works for a major law firm here and specializes in international patent law.  According to her, all of Canon's IP is protected legally, so in that context wherever their patents and copyrights are recognized, reverse engineering would not be legal.  Given that Canon's patents over the RF mount and associated firmware are very new, I think it is safe to say that reverse engineering is not going to be happening with any company that wants to do business with Canon again.  She said that Canon could have slapped a law suit against those who have infringed already, but they fired shot across their bows with a cease and desist letter - it has happened on the quiet with other camera makers, she added.

[deebatman316]

I would've thought reverse engineering would be completely outlawed everywhere apparently this isn't the case. As far as the EF Mount I don't know if there patents have expired or not. The RF Mount has new patents that haven't expired.

-Demetrius

40D, 5D Mark IV, EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 28-135mm F/3.5-5.6 IS USM, EF 50 F/1.8 STM

430EX III-RT & 600EX II-RT

[Tronhard]

If you read my post you will understand why none of this applies here.  Canon's gear is patented up to the hilt.  The EF mount came out in 1987, so it could well have lapsed its patents by now. 

It makes no sense for the makers of 3rd party lenses to reverse engineer when they can get a license agreement with the OEM, get updates and avoid litigation. It is quite difficult to reverse engineer firmware, and honestly not worth the effort and risk if is not well done.  Canon and other makers have very good relationships with Sigma and other quality lens makers, because they recognize the benefit to their camera and peripheral sales to have for those who, for one reason or another, will not use OEM lenses.

[deebatman316]

I would've thought Canon's system was more locked down. I was always told 3rd parties had to figure it out themselves. Also that the OEM doesn't license out their proprietary communication. 

-Demetrius

40D, 5D Mark IV, EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 28-135mm F/3.5-5.6 IS USM, EF 50 F/1.8 STM

430EX III-RT & 600EX II-RT