advice needed please

snapharry

snapharry

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kev
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right here goes im have a tamron 70-300mm lens which is spot on but i really like to get out and take wild life shots and the above said lens dosnt go far enough if you know what i mean and with the pennys being tight im i right i thinking if i get a converter it will increase the lenght i can see with the tamron any advice please :help:
 
depending on the converter you may lose AF ...

also a 2x will reduce your f stop by 2 stops, a 1.4 by 1.4 and a 1.7 by 1.7.

It's certainly a cheaper option than going for a 600mm f4.
 
thanks for the reply but sorry im new to photography and dont really know what that all means sorry once again
 
A converter is a lens itself. You will be adding a lens between the scene you want to photograph and the sensor in your camera. This lens (like any lens) will reduce the light getting through - so, all other things being equal, your shots will look darker.

The stronger the magnifcation, the more pronounced the effect.

AF= autofocus. Some convertors will relay the signal between the camera and the lens, but some wwill not, and so you will have to focus manually.
 
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If you get a teleconverter then it will reduce the effective aperture of the lens. With your lens it will reduce it too much and the camera will be unable to autofocus.

If you want something better then look at the sigma 150-500. Is £600 new from the likes of panamoz.
 
Lynton said:
depending on the converter you may lose AF ...

also a 2x will reduce your f stop by 2 stops, a 1.4 by 1.4 and a 1.7 by 1.7.

It's certainly a cheaper option than going for a 600mm f4.
Click to expand...

1.4x loses one stop of light.
By Lynton's maths a 1x (no change) will lose one stop.

He is dead right about losing AF. Two reasons.
1) The teleconverter may not support it. Beware of eBay 'bargains'.
2) Using your f5.6 with the 1.4TC gives an effective aperture of f8. You camera will not focus at f8; nor will any of mine. 'Taping the pins' to spoof the camera produces awful results that have never worked for me.

There's also the little matter that not all lenses are compatible with teleconverters; you gotta check they are compatible before buying.
Note: different manufacturers teleconverters have difference compatibility lists; if the Kenko is compatible, don't assume the Canon is, and vice versa, etc.

In my early days I bought a 2xTC for use on my 70-200 f4 without checking the forums - it was compatible but AF did not work and it has sat in the cupboard for years. It is finally getting some proper use now I have a 135mm f2, but it was a bad purchase.

In summary - a 600mm f4 may be a lot of money, but that's better than wasting money on a TC that you cannot use.
How about a used 100-400 ?
 
I've got a Kenko Pro300 DGX 1.4x teleconverter and with that I was able to get a Canon 100-400 f4-5.6 IS L (which made it an f8 equivalent lens) to autofocus on a 550D, 60D, 7D, 5D2 and a 5D3, and none of them were supposed to AF at f8. I've had a look at the compatability list of the Kenko and no Tamron lenses are listed, but whether the lens is physically compatible I don't know. If it fits there is a chance that it would enable your camera to AF with it on. As you're in Lincoln and I'm only about 4 miles outside you are welcome to come over and give it a try one day. Drop me a PM if you want to arrange a time.
 
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