There's been a couple of questions about teleconverters that's been bugging me for a while. I'm interested in these because I'm looking to extend the range of my 70-200mm f/4 lens without breaking the bank. Recently, I went to the zoo and couldn't get close enough for some shots with the bare lens alone. If I won some money at 4D, I'd probably buy over a 2nd hand 100-400mm f/4.5-5.6 IS, but that's a little far-fetched now.
I'm currently using it with an EOS 350D, which has a 1.6X crop factor.
Please be warned...n00b questions coming up! :sweatsm:
How much of an increment will a 1.4X TC give? Which is the accurate calculation?
1. (70 X 1.4) X 1.6 - (200 X 1.4) X 1.6 = 156.8-448mm
2. (70 X 2) - (200 X 2) = 140-400mm
Will the camera still autofocus with the central AF point if I use a 2X TC with this lens?
I've seen the Sigma TCs go for affordable prices. Should I look at this or go for other brands? Probably won't be able to afford a Canon though.
Thank you...looking forward to your replies.
I'm currently using it with an EOS 350D, which has a 1.6X crop factor.
Please be warned...n00b questions coming up! :sweatsm:
How much of an increment will a 1.4X TC give? Which is the accurate calculation?
1. (70 X 1.4) X 1.6 - (200 X 1.4) X 1.6 = 156.8-448mm
2. (70 X 2) - (200 X 2) = 140-400mm
Will the camera still autofocus with the central AF point if I use a 2X TC with this lens?
I've seen the Sigma TCs go for affordable prices. Should I look at this or go for other brands? Probably won't be able to afford a Canon though.
Thank you...looking forward to your replies.