Kenko 2XTeleplus Pro 300

Not really a lens question but it's not really a camera question either.
A while ago I took an example of the above in part exchange against a 100-400 I was selling, I didn't really want it as I have the Canon version but I did want the 24-105 that came with it. I put the extender on the for sale section but then thought I'd better test it and make sure it worked OK (should have done it the other way around I suppose) Any way I stuck it on my 1DmkIIn along with my 70-200 2.8 IS, not a dickie bird from it. It passed no info to the camera, it wouldn't auto focus; it didn't even set the IS in motion when the shutter button was depressed. I was half way through typing a sticking "you ripped me off" e-mail to the guy I did the deal with when I thought I'd try it on my 350d, it worked perfectly. I then tried it on my 20d, again it worked perfectly. I then put my Canon extender on The 1DmkIIn with the 70-200, no problems, I then put the Kenko extender back on the 1DmkIIn and again it didn't do a thing, it was completely dead. I tried looking on the Kenko site for info on this but no joy, the site is pretty useless. Any one got any ideas, surely if it works ok on a 20d and a 350d it should work even better on a 1D series.

It's the 1D's way of telling you NOT to EVER use it to take good photos...

kitacanon wrote in post #9320331
It's the 1D's way of telling you NOT to EVER use it to take good photos...

Can you post some examples of your bad photos with your Kenko 2x on a 1D body? The combination works well for me.

How can I do that? it doesn't work! at all on the 1D! I can't even set the apature with it on.

Clean all contacts and try again. If it works on a 20D it should also work on a 1DIIN.

Cesium wrote in post #9321137
Can you post some examples of your bad photos with your Kenko 2x on a 1D body? The combination works well for me.

It's all relative...I'm just spoiled by primes and adding extenders isn't satisfying....

Mick Emmett wrote in post #9322053
How can I do that? it doesn't work! at all on the 1D! I can't even set the apature with it on.

I was replying to kitacanon in a smartass way, not you.

As Gasrocks said, cleaning the contacts might help.

kitacanon wrote in post #9322366
It's all relative...I'm just spoiled by primes and adding extenders isn't satisfying....

So what you're saying is... is that you have little experience with (edit: this particular) teleconverter so you choose to bash on (it) blindly? Ok, got it.

Cesium wrote in post #9322613
So what you're saying is... is that you have little experience with teleconverters so you choose to bash on them blindly? Ok, got it.

Nooooo....I don't think you do...I have 40 years on and off effort with tele-extenders...and by relative, I mean others' standards and mine differ...
What I'm saying is that of the many budget converters I've tried, (promaster, vivitar, kenko), I've not found any 2x converters that satisfy my sense of IQ...
I'd rather recommend getting a sharper shot with a prime and enlarging the image afterwards, rather than combining a great lens with inferior glass...

Still, if I have to, and there's no other way of getting up close, I will use a 2xtender on my 300...but on any other shorter lens, it seems counter productive....

Clean the contacts!! I've had the dam thing in pieces and cleaned all the internal contacts as well as the outer ones but still no go on the 1d, strange how it works perfectly on both my other cameras.

kitacanon wrote in post #9322684
Nooooo....I don't think you do...I have 40 years on and off effort with tele-extenders...and by relative, I mean others' standards and mine differ...

Ah, the good old "I've been a photographer longer than you've been alive, son" argument.

Unless you have first hand experience with the camera, the lens, and the teleconverter in question, why comment on the IQ of the combination?

kitacanon wrote in post #9322684
I'd rather recommend getting a sharper shot with a prime and enlarging the image afterwards, rather than combining a great lens with inferior glass...

You must be joking!! the only way to enlarge the image "afterwards" is to do it digitally on the computer, I'll take the crappiest glass magnification over digital magnification any day. For those on a lower budget; an extender may be the only option anyway. I might just sell it with the proviso that it's only for 1.6 crop cameras.

I'm sorry Mick/Cesium that I've offended you...as I tried to say...everyone has different experiences and yes, yours clearly proves to be satisfactory to you both...

Well Er! thanks for your help anyway guys, I think!!!!