Kenko 2x MC4 (non-DG/DGX) for Canon.

[ZoneV]

I took a punt on one of these teleconverters to use with my Sigma 70-200 2.8 Blah-de-blah HSM II but after a quick play, all doesn't seem well: When I tried the Sigma and TC on my camera (1D mk2N), the top display flickered very quickly so I immediately powered off.

Does anyone know what's going on (I suspect I need a DG/DGX version) and whether there's a fix?

Thanks.

 

[ZoneV]

Update:

Can of worms! Despite the problem with the Sigma, the TC works fine with an old (25 year old) Canon 70-210 f/4 lens: no odd display flashing and it even has a go at AF (not tried in good light). Comparison of the two lenses revealed far more contacts on the Sigma than the old Canon, which has the same number of contacts as the TC. A quick google for images of the newer, Kenko pro300 TC shows more contacts - the same number as on my Sigma. Problem solved but what a PITA, I bought the TC with the Sigma in mind. :thumbsdown:

 

[modchild]

I had a Kenko 2x MC7 converter and that worked perfectly until I bought a body with a top screen and I had the same flashing/flickering. I emailed Kenko and they said it was to do with the contacts arrangement and it would not harm the camera. I only used it for moon shots on a slower lens so it was permanently manual focussing.

In the end though I sold it and bought a 1.4x Pro300 DGX version to pair it with a Canon 70-200 f4L non IS and the IQ difference was massive and the ability to AF was great. When I eventually bought a 70-200 f2.8L MkII I got a 2x Pro300 DGX to see how much it affected the IQ but it arrived faulty and couldn't AF with it. The IQ in manual focus was very good though, much better than the IQ from the MC7.

I returned it and bought a Canon MkIII 2x converter instead and the IQ from that on the 70-200 is IMO better than the IQ I got from the Canon 100-400 L I used to have. I also use the Kenko 1.4x with the 70-200 and the IQ from that is very good also and I could also retain AF with the 1.4x and Canon 100-400, even though it was at f8, which was a big bonus.

In essence, if you really want a 2x converter, and don't want to be restricted to a certain few lenses with the Canon converter, then the Kenko Pro300 DGX 2x is a very good alternative and worth investing that bit more.

 

[ZoneV]

Thanks for the useful advice, Stuart, and confirming my suspicions about this one.

That'll teach me to to take a punt on something I see going cheap without doing some research first!