Focus Speed drop off with converters ?

[Lepus]

Hi all , more out of interest than anything . But from what I have been reading , the 2x converter significantly slows down the A.F even on fast primes . As I rarely take the 2x converter off my 300 f2.8 , I have to say it often feels very slightly under par , though I have had excellent results also and have not attempted Micro AF adjustments with my combination . I was wondering , do the likes of the Sigma 150 - 600 zoom focus faster than my combination at 600mm , and could it possibly be as sharp ? Have also read bits that certain camera bodies focus faster / better , any truth in this ? I am a little tempted to sell my 300 f2.8 Mkll , and get a second hand earlier model 500mm F4 , but that lens is getting older , and not sure if it`s the right way forward , appreciate all comments and thoughts .

[paul linton]

Re: Focus Speed drop off with converters ?

If you sell your 300mm you might have to let me know first!

Paul

[TonyT]

Re: Focus Speed drop off with converters ?

It slows the older 500 as well as I have one, the 1.4 tends to be quicker, the 300 2.8 x2 combo is supposed to be a match made in heaven from what I have heard. The Mk 3 extender is supposed to be quicker on the later newer lenses.

All in all I notice the x2 slowing down the focus on most of my lenses and it is a MK3 version.. i.e on the 500 F4, 100-400 MK1 and MK2 and not so much but still on the 70-200 2.8 Mk2.

For the 500 people swear on the 1.4 times as a match made in heaven, so much so I never used the x2 at all until I forgot the 1.4 one day, I probably use it more than the 1.4 now... For what it is worth the 300 combi is supposed to be a cracking airshow set up and whatever you use it for, you would know the disadvantages of the 500 when it comes to carrying it and swinging it around.

[the black fox]

Re: Focus Speed drop off with converters ?

a lot also depends on the camera body your using mark ,for instance my 80D was fairly slow to lock on to b.i.f while the 1D3 was lighting fast .my current 1D4 tends to fall between the two ,but I believe it can be overcome in the settings but you lose some accuracy , if you did go down the path of one of the sigmas you would also lose a fair bit of light gathering ability and find your using much higher iso values ,theres no magic elixir I'm afraid

[Lepus]

Re: Focus Speed drop off with converters ?

Thanks everyone , I am not that tech minded , it may just be I havn`t set my 5D mklll up to get the best out of it , I have very little time to read stuff and get a proper understanding of such things . I was aware of light loss on the zooms Jeff , but I try and stop my combo down to F8 when I can anyway , and high iso is becoming less relevant of late it seems .
I am also thinking about the extra weight Tony , though my main targets are Deer and Hares , though this involves a good deal of walking , creeping and crawling , not so much swinging and hand holding . I`ll keep dreaming and thinking about it .

[TonyT]

Re: Focus Speed drop off with converters ?

Mine is on a 1DX if it matters, I carry the lens mounted on a monopod and over my shoulder with a pad on the monopod, can you not find one to try lifting etc, it is heavy, especially after a hour or so, I certainly wouldn't want to crawl with it.. I do have a rucksack to carry it all in though.

One of these, carries the lens with hood extended, and camera body on it, if I put a converter on it is really to tight to zip up. has a side stowage for a tripod monopod that comes with it.. I use it to transport it in my car.

http://www.wexphotographic.com/lowepro-lens-trekker-600-aw-iii-1559859/?mkwid=sZmu3nX54_dc&pcrid=89741382779&kword=&match=&plid=&si=&gclid=EAIaIQobChMIpvK01Ly21gIVHZSyCh1SggUlEAQYAyABEgJ9HvD_BwE

[the black fox]

Re: Focus Speed drop off with converters ?

I will add I have used quiet a few different 1.4 t.c's with my sigma lens since owing it canon mkii and mkiii ,kenko HD ,but I have now settled on the dedicated sigma one and find there is no discernible difference in either speed or quality with it ,you just need higher ISO values