M6 ii+70-300 IS USM ii+teleconverter

Andy01 wrote:

KEG wrote:

Andy01 wrote:

AFAIK none of the Canon 70-300mm lenses (incl the L lens) are compatible with the Canon TCs.

I do have a vague recollection seeing a post or two mentioning that there was a 3rd party TC that worked, but I can't remember which Canon forum it was in. Perhaps try a search in the Canon forums ?

Colin

The Canon 1.4 one is apparently compatible at 200-300mm with the 70-300L

Well yes. I was referring to "full" compatibility. I would not want to try to remember not to zoom back and have the lens & TC make contact.

Colin

I've had a lot of luck using the 'lowly' EF-S 55-250mm IS STM with Kenko teleconverters and Kenko optics.

You can see some photos I took this morning of birds with this setup here:

https://www.dpreview.com/forums/post/65439466

In my case I physically modified the mount of the EF-S lens so that it would mount on EF teleconverters. The rear element of the lens doesn't stick out so this works.

I use most successfully a slightly older Kenko 1.5x Teleplus SHQ teleconverter. The camera would not autofocus using the 55-250 and the 1.5x, but after I removed the electronics from that TC the combo works perfectly (except the EXIF data for focal length and aperture doesn't reflect the TC in the optical path).

The 1.5x SHQ only slightly degrades the sharpness and contrast of the EF-S 55-250 IS STM, so much so that I have a hard time telling which shots I used the TC for and which I didn't.

I also use a Kenko extension tube into which I've mounted the optics from a vintage Kenko MC7 2x teleconverter. The results are only slightly better with this setup than using the 1.5x TC and cropping. The problem is partly that with a 2x teleconverter you're now shooting 2 stops lower wide open at f11, and are past the 'diffraction limit' of the M6ii's high res sensor --- so at the pixel level the image is noticeably softer.

With a 2x converter, there is also the challenge that you need a lot more light.... but many in this forum have recently discovered that DxO's Photolab 4 and its Deep Prime Noise reduction appears to be a game-changer and lets us push images one or two EV higher, and still get great results. I used DxO to process all the images in the referenced post.

Here's a link to another post with some of my sample images - that thread contains links to more of my posts where I share details of how I modified the lens and the teleconverters.

https://www.dpreview.com/forums/post/65366346