Canon 300 f/2.8L IS and extenders

[grumpybadger]

OK. This may seem a bit bizarre. I have a Sigma 300 f/2.8 EX that I bought on here and I have to say that it is a corker of a lens. Without a teleconverter, the AF is fast and accurate and it seems to be a sharp lens.

However, with a 1.4x or certainly a 2x extender, the AF really starts to suffer. It is sluggish and without a focus limited can be a real pain if you lose a bird.

On that basis, I've been considering hiring a Canon 300 for a trip to Scotland. I'll be using my 500 for most stuff but it really is too heavy for prolonged birds in flight stuff. So, the question is, how good is a Canon 300 with 1.4 or 2x extenders at tracking moving targets?

Thanks

Paul

[CarlOgden]

It's been muted on the internet that the extenders were created for this lens (although they fit every L Lens) and I've got both 1.4 and 2 and do use them (not much to show on here though!).

If you're not happy, then go with your idea of hiring!

Carl.

[IanC_UK]

I have also heard the converters were created for the Canon 300 2.8 lens, and it works extremely well with them from all reports ! I am hiring one for Iceland in a couple weeks can let you know unless you need to know before then ? :)

[moomike]

I found the AF to slow down only very slightly with the 2x convertor, didn't make enough difference to the 1D's AF performance for me to not use it. The 1.4 is marginally faster & spot on for wildlife tracking imho :thumbs:

I'd watch with hiring that lens though as I'm sure you'll wind up wanting one :lol:

[mho]

I will also echo everyone else's comments they are very good, 1.4x very marginal loss of af speed, 2x slight loss in af speed still fast but noticeable.

[dazzajl]

Last time I used the 300 f2.8 with a 2x I was playing at tracking birds from a very lively little boat and it was pretty impressive.

Fairly sure that was only on a 5D too.

[grumpybadger]

Thanks guys. I've seen results that certainly convince me optically that it is ok. I do expect that if I hire one, I'll want one but I'd rather risk 2 weeks hire to see than full price for the lens.

I actually bought the Sigma to see if it was a useful length for me and it is... So, it's just a matter of whether I take the plunge or not.

Ian - your take after Iceland would be great. I'm not doing this trip till early June so should be ok...

[busterboy]

Can only echo others comments.:)

I have the 300mm and both 1.4 and 2x converter and can confirm its still lightning fast AF.:thumbs:

[IanC_UK]

Ian - your take after Iceland would be great. I'm not doing this trip till early June so should be ok...

Ill be back before then so can definitely give you some feedback :)

I want one anyway so hiring is just so i dont have to find a load of money now ;) lol

[malla1962]

Im with the others on this one, it is still fast with converters.;)

[grumpybadger]

Having hired one from LensesForHire I was very impressed. I was originally thinking of getting another 400DO but I think I'm now going to get a 300/2.8 and 400/5.6 as it will be cheaper and more versatile.