Which TC

[pjs2]

I have the Canon 50D
I am going to buy the Sigma 70-200mm f/2.8 EX DG OS HSM
I believe a great all round lens even in low light.
along with either the Sigma 1.4 x or the 2 x teleconverter
I mainly shoot Rugby league (mainly from 2:00 pm and later) Nice and close to the action.
Want to try my hand at surf photgraphy.
Do I buy the 1.4x with the 280mm reach @ f 4 or go for the 2x with the 400 reach @ f 5.6 .
Would I loose to much quality with the 2x.

[gw.toad]

I'm not sure what sigmas T/Cs are like...I had a x2 in another brand and it wasn't much good it tended to have a blue tinge on some of the outer image...

[Boo53]

I had a Kenko 2x tc which I used with my sigma 120-400 and was not happy with it, soft & tending to blue , so replaced it with the sigma 2x tc and I'm quite happy with the combination

[Cage]

I have a Tamron 1.4 T/C I use on my Sigma 70-200 f2.8, and most of the time I cant see any image degradation at all.

I've tried 2X T/C's and always felt I got better results with no T/C and a crop.

[William W]

I’ve neither used the lens nor either Sigma Tele-extender so I am not commenting on any definitive IQ loss: but addressing the matter this way –

Rugby League, (winter) after beginning 1400hrs, (assumed in QLD) with a 50D.
What’s your comfortable ISO limit on the 50D – let’s say ISO1600.
What is an average case shooting scenario – second half beginning at 1530hrs on a very lightly overcast afternoon, and typical FRONT lighting EV = 13.
For most shots you will need to pull Tv = 1/800s as a limit minimum for most games of a reasonable standard, Tv = <1/1000s min. is preferred.

At EV = 13 and at ISO 1600, you can shoot: F/8 @ 1/1600s @ ISO1600, which stops the lens down ONE STOP from max aperture to somewhat account for IQ deterioration when using the x2.0 tele-extender – so in theory without having used the gear this seems a reasonable proposition.

BUT what would be a reasonable and common worst case shooting scenario?
If you are shooting into the light (in the light overcast afternoon scenario above), you will need about TWO more stops, which you have and you could pull: F/5.6 @ 1/800s @ ISO1600 . . . or other variants such as: F/5.6 @ 1/1600 @ ISO3200.
So that seems also reasonable and in theory would allow some wiggle room to adjust the least weakest exposure parameter to attain the best possible image.
But if you think you will be shooting in full cloud in the later afternoon (e.g. EV = 10) and you really do not like shooting at ISO3200 or faster – then you might be better thinking about buying the x1.4 and cropping when you do not have the reach.

In any case, I suggest you look at past photos (if you have them) and study the light you actually do have with which to work.

For surfing (in summer?) – I guess you will expect a bit more light and also the assistance of reflected light which will enable you to pull F/8~F/11 adequately at suitable shutter speeds maybe even at ISO800 - (in theory lessening any IQ degradation).
So the x2 tele-converter seems to be a better answer: because although I have not done a lot of surfing photography, when I have using a 400, 500 and 600mm lens was the answer – so on an APS-C camera, a 400mm reach is much more appropriate than 280mm.

So relating that back to the football – how close are you to the action at the footy? – close enough to use the 70 to 200 native, if you have to?

WW

[pjs2]

Many thanks for your help folks.

I think I have solved my problem though. Thanks to another post on aus photog I found that for the same money + $200 or so I can afford not only the 70-200 but 150-500 as well. So at this point I wont need the tc. I have to buy from overseas, not something I've done before but I'm going to be brave and give it a go. Would like to keep my money local but to good an oppertunity to pass up.


WW very usefull info.

Thanks
Peter

[dulvariprestige]

I've got both those items, 70-200 OS and 1.4, and they do work really well together

Wide open @ 280mm
http://farm7.staticflickr.com/6009/5914490135_8400556cbb_b.jpg (http://www.flickr.com/photos/dulvariprestige/5914490135/)
Cormorant (http://www.flickr.com/photos/dulvariprestige/5914490135/) by Jayde Aleman (http://www.flickr.com/people/dulvariprestige/), on Flickr