Canon 350d with a sigma 70-300 Apo, Teleconverter?

[Stavhp]

hi guys,
will my sigma 70-300 f4-5.6 apo work with a 1.4X teleconverter on a 350d body?
if so would i loose autofocus?
i have had a look at the teleconveter thread but i am confused, sorry:oops:

stav

[GNMink]

You can look on the Sigma web site, but I don't beleive the 70-300 will work with the teleconverters

I've got a sigma catalog here and all the lens that work with the teleconverters say they do in the descriptions, but no mention on the 70-300 I highly doubt it will work.

[ron chappel]

There are a couple of potential issues

The autofocus will very likley work up to about halfway through the zoom range.When using the longer end ,you'll have to manually focus.
At least that's what happened when i used a TC with the EF100-300usm lens.
The other issue is to be carefull which TC you get.I think canon brand ones for example will only work with the longer lenses.From what i've heard,most non canon brand TC will work on most lenses (?)

Just one other thought...
The 70-300APO is quite good as far as consumer telezooms go,but with a TC added i'm guessing the optical qualities at the long end will be rather cheap and nasty.

[Stavhp]

OK, thanks ron and major, i think i have just found an excuse for another lens:D
Now where to get the money:rolleyes: :o

[dmwierz]

Ron is correct. I have this lens, and the Sigma 1.4 TC, and the two are not compatible.

The Sigma site even says so:

http://www.sigma-photo.com/lenses/lenses_chart.asp