What TC for sigma 150-500mm on Nikon D7000? (1 Viewer)

Hi,
can anyone advise me on what teleconverter will work with AF (if any) for a Sigma 150-500mm DG 1:5-6.3 APO HSM OS on a Nikon D7000? From other threads I've read Kenco seems to be the way to go. I am off to Namibia next year so the light intensity shouldn't really be an issue.

Thanks

Andy Hurley said:

Hi,
can anyone advise me on what teleconverter will work with AF (if any) for a Sigma 150-500mm DG 1:5-6.3 APO HSM OS on a Nikon D7000? From other threads I've read Kenco seems to be the way to go. I am off to Namibia next year so the light intensity shouldn't really be an issue.

Thanks

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I would advise you to borrow a converter and test it with this lens first, otherwise I think you are going to be disappointed.

AF will not work on this lens with a converter on, so will have to be manual focusing, plus image will not be great either.

Kenko DGX series TCs will attempt to AF even at tiny apertures (mine does so at F11!) but there is a good chance that they will not be able to lock focus.

Thanks very much guys.
I suppose I can crop a lot more with the d7000 than with my previous d3000 so I have to be content with that.

AndrewG said:

AF will not work on this lens with a converter on, so will have to be manual focusing, plus image will not be great either.

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It will with a kenko 1.4 dgx tc(it does on mine)& the images are fine too.:t:

Cheers.

Steve.

stevo said:

It will with a kenko 1.4 dgx tc(it does on mine)& the images are fine too.:t:

Cheers.

Steve.

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It depends on what Camera you are using - the OP was asking about it with a Nikon D7000, is the the Camera you are using??
I don't know anything about Nikon's but on Early Canon DSLR Cameras (up to the 30D) these converters (inc the DGX) and also taping the pins on any other converters worked fairly well but IQ is down to your expectations, some folks find it OK but others will be bitterly disappointed. With later Cameras that have enhanced AF points things are not so good, especially when using the centre focus point.

Admittedly i`m using this convertor on an eos 50D & 1DMK2n,with reliable af.

Steve.

stevo said:

Admittedly i`m using this convertor on an eos 50D & 1DMK2n,with reliable af.

Steve.

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Well the 1DMK2n is meant to AF at f8 so no surprises there Steve. As far as the AF on the 50D goes you may well be satisfied with it but there are lots of people who would not be that's for sure. When it comes to AF and IQ with converters on these slow lenses 'one man's meat is another man's poison'.

Yep I understand your point Roy its only in times of desparation that the convertor goes on,mostly gets left off.

Steve.

I have a Nikon D300S used with a Sigma 150-500mm.
Tried the Kenko 1.4 DGX, although it auto focuses was never really impressed with the results.
Also you need a LOT of light

My Sigma 50-500mm OS will AF with the Kenko 1.4 DGX on a D7000, so your 150-500 probably will as well. That said, I never use it with a TC because the images are very soft, even stopped down, so you're probably better off cropping.

I agree with the other posts - that you are probably better to avoid a teleconverter with the 150-500. Generally images are going to be slightly soft and not better than cropping.

There is a bit of a misconception on AF with teleconverters. AF occurs with the lens wide open, and then it is stopped down electronically at shutter release. So regardless of your aperture selection, the ability to autofocus is based on the widest aperture of the lens or lens and teleconverter.

Different sensors have different capability of AF. The center sensor is the one that has the best AF performance. The adjoining cross sensors perform at a stop lower - so if you get AF at f/8 with the center sensor, it is f/5.6 with the adjoining cross sensors. There are 39 sensors on the D7000 and the outer sensors that are not cross sensors lose still another stop - and they are less reliable and accurate to begin with.


You lose a full stop with a 1.4 teleconverter - so f/6.3 fully zoomed becomes f/9 with a 1.4 teleconverter. That does not mean that you can't focus at f/9 - just that it is not as reliable and requires very good light and a good focus target. And all this assumes you are using the center sensor. With a lens that is at f/6.3 fully zoomed and a 2x teleconverter, you lose two stops. That puts you at f/13 wide open which is very difficult for AF.

I would not rule out trying the Kenko Pro 1.4 teleconverter. In some situations it will create nice sharp images. It is better with closer subjects and good support. Just be aware that in marginal light or with distant subjects cropping probably going to be better. The percentage of keepers using the teleconverter is going to be low. You may find it is better for recording what you see than for high quality prints.

I have the 150-500 apo with the sigma 1.4xtc
You loose auto focus so I actually use live view zoom in
manually adjust the focus mind you this is for steady subject only
mirror lock up get my shutter release cable and take 3 shots

Depending on the distance to the bird you can get some keepers
and will have to do some serious sharpening alot of detail is lost
the images sometimes come out almost dream like. But if it's a matter
of identifying and capturing the bird you will use the tc just for the distance
just don't expect a wall hanger shot out of it.