p.1 #1 · 100 400 II - 7DII plus Kenko 1.4 DGX = no connection
While feeding my squirrel this morning a pilated woodpecker flew over. He landed in trees a distance away so I ran inside to grab my camera and wanted a teleconverter. The Canon 1.4 was upstairs but the Kenko 1.4 was in my camera bag where I had it for use with the 70 300L I'd been using after selling my 100 400L for day trips. so I grabbed the Kenko and stuck it on, but immediately got the No communication, clean your contacts error. This was on the 100 400L II with the 7D II.
I then tried the Kenko with the 1DIV and the 100 400L II. It worked fine. So I went back and tried the 7DII with the Kenko and the 70 300L and it also worked fine.
The only combination that doesn't work, and I tried it again just to make sure, was the Kenko with the combination of the 7DII and 100 400 II. The Canon 1.4 Version II works fine with it.
Just FYI, if anyone else has this teleconverter and it could be something crazy with just my copies. ??
p.1 #2 · 100 400 II - 7DII plus Kenko 1.4 DGX = no connection
My cousin tried the Kenko 1.4 300 DGX on his 7D II with the 400 5.6. Not only didn't it work, he had to take the battery out to shut off the camera. The same combination worked great on a Canon 60D.
p.1 #3 · 100 400 II - 7DII plus Kenko 1.4 DGX = no connection
I thought I was just my 7dmk2 and 400 5.6 that was locking up with the kenko 1.4x 300 dgx. The old 100-400 and 7dmk2 and kenko work with all focus point but if you try to micro adjust the combination you get one value in the camera and another value when you review the photos.
p.1 #4 · 100 400 II - 7DII plus Kenko 1.4 DGX = no connection
hulgar wrote:
My cousin tried the Kenko 1.4 300 DGX on his 7D II with the 400 5.6. Not only didn't it work, he had to take the battery out to shut off the camera. The same combination worked great on a Canon 60D.
I have a 'Yellow DOT" version of the DGX and have observed the same problem.
I have to remember Kathy's observation and use the Canon 1.4X when my 100~400 V2 arrives
p.1 #5 · 100 400 II - 7DII plus Kenko 1.4 DGX = no connection
If cleaning the contacts doesn't work try exercising the lens extender's springy pins by lightly pushing them in & releasing repeatedly when you are cleaning them.
I suspect some kind of electrical resistance due or dirt or corrosion on the contacts and pins of all mating parts and/or electrical resistance in the springy pogo-pin contact internals of the extender. I assume that their pogo-pins pass thru the converter body, inside holes in a single insulating block, directly between the lens/camera flanges w/o wires, flex ribbon, or any other electronics like their extension tubes that I have taken apart. The pogo-pins are simple in design being a pin that slides in a tube with a spring in-between. Better pins will have additional parts inside to insure electrical contact between sliding surfaces.
p.1 #6 · 100 400 II - 7DII plus Kenko 1.4 DGX = no connection
Same situation with my 5D III and 400/5.6. Locks up and have to recycle the main battery.
The Kenko works with my 70-300 L which is what I bought it for.
The first Kenko TC I tried with the 5D III and the 70-300 L was not the Pro model, it gave a very erraticr frame rate and seemed to affect the shutter movement. IE, a few frames were black in the bottom half. It would start shooting at a fast rate but then really slow to an erratic rate.
A similar version owned by a friend worked properly. No idea why but I was not prepared to risk the camera by experimenting.
Edited to add: the Kenko I currently have is the C-AF 1.4X Teleplus Pro 300 DGX.
Made in Japan with a yellow dot after the Japan word. Works on the 70-300 L but as I mentioned, locks up the camera with the 400 F/5.6.
p.1 #9 · 100 400 II - 7DII plus Kenko 1.4 DGX = no connection
I only have the Kenko to go with the 70 300L so no real problem for me. I was just a little surprised. I am thinking I just may sell that lens shortly anyway because I actually only kept it due to the AF being so much faster than the 100 400L and at this point I'm thinking the VII will do quite nicely for all the uses I kept the 70 300 for, all in one lens. The only real advantage now would be weight.
p.1 #10 · 100 400 II - 7DII plus Kenko 1.4 DGX = no connection
I find it interesting that there are several brands with the same apparent issue with the same camera lens & camera combo.
Could this be a worst case electro/mechanical tolerance stack-up issue between these brands of converters and the same Canon lens/body combo creating some % number of perfect storm failures?
I suspect that these extenders are made and rebranded for Kenko, Tamaron and Bower by the same company and probably share many parts causing the similar issues.
See Adorama's page for images of telextenders here
The 1.4x extenders & 2x extenders look the same between brands.
BTW I am not endorsing only Adorama as I purchase from other suppliers.
p.1 #11 · 100 400 II - 7DII plus Kenko 1.4 DGX = no connection
Rusty1 wrote:
My tamron 1.4 will not work with the 100-400 vII on the 7DII. The Canon 1.4 vII works very well. Crafty old Canon.
Yeah, but that's what happens when reverse engineering is insufficient.
I have one of the those Kenko/Tamron TCs around somewhere from the 50D era.
It probably won't work on anything newer than that.
