400mm f2.8 ver 1 with 2xIII

I am looking to purchase a 400 2.8 version 1 and match it with a 2x version III. my question is how will the af system react with this combination on the 7D, will it be slow to focus and will the images be decent or very good?

if anyone has this combination and could post some picks it would be appreciated.

Thanks
Keith

Reffuring to https://photography-on-the.net …/showthread.php​?t=1345000 thread I see you have a 5DII in your signature.
A 100% crop from that body came out BETTER than the uncropped picture from a APS-C camera with 2xIII.
IQ wise you'll get a lot more fringing.
With TC you lose a bit of speed not a lot, it still goes fast enough for moving things.
Good luck,

Since your lens is version I, I'd not waste the extra money on the III TC. I'll bet the II TC would work about as well.

gasrocks wrote in post #16849868
Since your lens is version I, I'd not waste the extra money on the III TC. I'll bet the II TC would work about as well.

I can't comment on the 400 F2.8 as I sold mine quite a while ago, however in the cases of my 300 F2.8 L IS Mk1 and the 600F4 L IS Mk1 the improvement with the 2 x Mk3 is very significant. I had the Canon 2 x Mk2 and it was emergency use only, the Mk3 (in good light) gives nice A3 prints, that is quite an improvement in my experience.
True you don't get the full (AF etc) benefits on the earlier lenses buy the IQ improvements are well worth it. This does not appear to be the case with the 1.4 - or so I read.

Thanks Lenty, Gasrocks, and John you comments are greatly appreciated and will be taking under advisement. I shoot primarily wildlife and more specifically a lot of birds so image IQ is paramount and especially with the smaller birds as i sometimes need to crop due. i was also looking at the 150 -600 tamaron but heard it didn't fair so well with the Canon 7D.

Keith

I have the 400 f2.8L MKII non/IS and for what I shoot primarily surfing competition/events I often use the 2xII with excellent results. I have not done any bird/wildlife photography and mostly I've seen they use 500/600 lens.

Anyways, these following thread might help you sort it out in your search...

https://photography-on-the.net …read.php?t=6616​55&page=44

https://photography-on-the.net …read.php?t=5296​92&page=26

https://photography-on-the.net …ead.php?t=12276​63&page=93

Goodluck to ya.

This attached file is one taken on my very first outing with the Canon 300 F2.8 IS Mk1 + Canon 2 x Mk3. It is not necessarily the best but it is one of the first shots taken. Note this is an unprocessed RAW file converted to JPEG and scaled for web, obviously it would look better when processed up but this should give you an idea of what comes out of the camera - 1D4 in this instance.