Canon or Sigma TC's

[mwrmt]

Hi all.

Just looking for some insight into the teleconverters offered by both Canon and Sigma.

I have a T2i and use a 17-40mm f4, a 70-200mm f4 and a 50mm 1.8.

I'm looking for a bit more range outdoors w/out having to go to a bigger lens.

I know Sigma's filters come highly rated and have them on all of my lenses, but was not sure about their TC's.

I'm not liquid with $$$, but if the Canon's are worth the extra, then I'll go that route.

Thanks and have an AWESOME day!

PS - is there really any need for a lens hood on a 50mm f1.8 lens?

[ktuli]

Mike,

You may want to research the Canon's some more - I know they only work with specific lenses (usually L lenses). I don't know off hand if those lenses you listed would even work with the Canon.

That being said, I know that most people will say you're supposed to have the matched TC for your lens for the best results. I have a Kenko TC that works just fine for me. If it has image degradation, I can't see it... or it just doesn't show up in the kind of shooting I do.

- Bill

[benm]

I know nothing about Canon lenses so can't comment. But I can recommend using a lens hood on every lens, including a 50mm.

[Geoff F]

The problem with Canon teleconverters, Mike, is that they will only physically fit a limited number of lenses, as Bill mentioned.

They should fit your 70-200 L lens OK and work without any significant problems, except for a slight reduction in quality and light levels. And to be honest, if you want greater range that is the only lens from your selection which matters anyway.

I say 'should' to cover myself because those Canon converters work fine with my 70-200 L IS F4 lens so I'm assuming that yours is the same as mine and not a different version. As far as I am aware all 70-200 L lenses are OK, but . . .

The second point is which converter? The 1.4x shouldn't be any problem but you are likely to suffer more quality loss and auto focus problems with a 2x.

So is it worth getting a 1.4x converter which will increase your length to around 280 mm. Well it depends on what alternatives you consider and personally I would say that a 70-200 plus converter is better than anything else around that range. Unless you go up to the new 70-300 L which isn't cheap.

In fact anything which is a credible alternative isn't cheap. My only slight concern would be, is 280 mm a sufficient gain for you. If not, you may be better off to put that money towards an expensive significantly larger lens.

[Rob Douglas]

Mike, first off, the hood on a 50mm1.8 is a waist. It is about half an inch in depth. I would just be careful and save your money. As for the TC, your lens will be fully functional with both. A 1.4 TC at f/5.6 & 2x at f/8.

[mwrmt]

Thanks guys.

Bill, both the 17-40 and 70-200 are L glass and the 50 is an EF lens. I'm just curious because of my body being a T2i and not something "better", like the 60D or 7D.

Ben, appreciate the insight and will get one ASAP.

[mwrmt]

Geoff, Rob.

Thanks guys. The extra distance would be great, but my real question is, are the Sigma tc's that good, as they are a fair bit cheaper than the Canon's. I know they knock off a stop or 2, but as they would be used outdoors, I don't see that as a real issue.

Again, thanks.

[Jim B.]

You also might want to take a look at the Kenko 300 pro 1.4x.
It get's good reviews.

[William W]

Just looking for some insight into the teleconverters offered by both Canon and Sigma.
I have a T2i and use a 17-40mm f4, a 70-200mm f4 and a 50mm 1.8. I'm looking for a bit more range outdoors w/out having to go to a bigger lens.

Depending upon the Extender you buy, you WILL HAVE various functionality differences.

Mounting:
The Canon EF Extenders will NOT mount on your 17-40L nor will they mount on your 50/1.8.
Third party extender might mount on those two lenses.

The Zoom Lens:
On your zoom lens and using that camera there will NOT be full functionality in all situations with any x2 extender and there will be likely be functional variations using a x1.4 extender, irrespective of the brand of the extender.

***

Specifically
X1.4:

The Canon EF 1.4x MkII Extender, (and MkIII version)) will work with your camera and mate with your EF70 to 200F/4L USM lens - (if you made a typos and you have the EF70 to 200F/4L IS USM it will work with that lens also).
You will lose one stop, effectively making your lens an F/5.6 zoom.
Your camera should Auto Focus with this combination, but it will likely only AF at the centre AF Point.

***

Specifically
X2.0:

The Canon EF 2.0x MkII Extender (and MkIII version) will also attach to your lens OK, but you will lose Auto Focus, with your camera as you effectively make the lens an F/8 lens.

If you use a third party tele-extender, even a x2.0 version, you may still “attain AF with your camera” because some third party extenders do NOT convey all the data from lens to camera to lens so the camera does not know it should not be attempting AF: BUT you will still lose either 1 Stop (for a x1.4) and 2 Stops for a x2.0 and 3 stops if you go mad and get your hands on a Kenko x3 extender.

And when you get to losing TWO stops, then the lens is effectively at F/8 the camera AF is working very hard even if it not being told that it should not be trying to make focus – so you will often get vague wandering through focus or “focus hunting”.

Attempting to Manual Focus at F/8 is not that much fun either.

***

Opinion and tests:

I reckon the Kenko Pro 300 series x1.4 will be better than the Sigma x1.4, BUT I have not use the Sigma and I have used the Kenko.
I also KNOW that, using the EF70 to 200F/4L IS USM and the native lens at F/4~F/5 (i.e. shooting F/5.6~F7 with a x1.4 extender attached), the Canon MkII extender, is noticeably better than the Kenko on an 11 x 14 print – but that is on a 5D – and most of the image degradation is at the edges, so therefore on an APS-C camera that might not worry you.

Also it is difficult to ascertain how picky you are and how picky I am and also what is the intended use of the images – 5x4 prints or computer slide shows are different to wall hangings, as one example.

In any event there are TWO elements which must be pristine:
> Exposure must be SPOT ON
> Post Production technique, especially sharpening must be excellent.

***

Bottom Line:

In all of this I suggest you really consider what it is you will be photographing . . . and take a long think about what that will be:

For example – if you want this extra length to get some shots for the Alouette United Soccer Club, then think about what that will be like to shoot . . . you’ll need to keep the shutter speed at about 1/1000s or faster - - - consider you are shooting later in the afternoon, and you have modest cloud cover - then you will be around ISO3200~6400 if you are limited to an F/8 lens and you might need ISO12800 if it is heavy cloud. . . so would a x2 extdender be suitable ? ? ?


The question is not just about "wanting more reach outdoors" the question is about wanting more reach outdoors to photograph xxxxxxxxxx in yyyyyyyy situation.


***

is there really any need for a lens hood on a 50mm f1.8 lens?

Re the Lens hood for the 50/1.8 – it depends, but the lens hood certainly should NOT be dismissed as a waste.
The lens hood is not so much about lens protection for this lens it is about IQ.

The front element of the lens is well recessed and the lens is pretty hardy apropos avoiding flare – but personally I would buy the hood as I would be using a 50mm lens often outdoors or inside in high intensity close range, single source lights (like a Gymnasium or small sports arena) or for Outdoor Flash Fill Portraiture where the sun is likely behind or top-high and side to the Subject – and in these shooting scenarios, a lens hood ON will address more Flare issues than no lens hood.

If you are not using the 50mm lens in scenarios where you are shooting into the light – then maybe this is not an expense you require.

WW