The effect of a 1.4x teleconverter on aperture and shutter on a 80-200mm f/2.8 lens

<p>I currently use a Nikon D300 and D300s. I’m considering the purchase of a 1.4x ($510) or 1.7x ($540) teleconverter for sports photography. I have an 80-200mm f/2.8 lens and a 70-300mm f/4-5.6 lens. If I understand it correctly, a 1.4x magnifies both reach and aperture, which means:</p>

<ul>

<li>80-200mm f/2.8 would be converted to 115-280mm f/4</li>

<li>70-300mm f/4-5.6 would be converted to 100-420mm f/5.6-8</li>

</ul>

<p>Is that correct?</p>

<p>Since I want to use it primarily for sports, I want to keep my shutter speed in mind. I like tripling my shutter:lens ratio (keeping it between 1/1000 and 1/1250 for day sports). My shutter speed would also have to be increased to compensate for the teleconverter, right? If I shoot the minimum at 200mm f/2.8 1/600, the new length would be 280mm f/4 and I’d have to increase the minimum shutter to 1/1000, right?</p>

<p>The cost of a refurbished 300mm f/4 is about $1,300. Should I save my money and invest in the 300mm f/4, or cut the cost and get the $510 TC-14 teleconverter?</p>

<p>Any suggestions would be greatly appreciated.</p>

<p>I assume you have Nikon's TC-14E II and TC-17E II in mind. What you wrote is correct for the 80-200mm/f2.8 as long as you have the AF-S version. Those teleconverters cannot be mounted onto the 70-300mm f4-5.6 lens (and f4-5.6 is not the AF-S version, which is f4.5-5.6).</p>

<p>If your 80-200mm/f2.8 is the AF or AF-D version, those teleconverters are not compatible.</p>

<p>Laura, the D300 cameras are DX format with a 1.5 crop factor already, so your 80-200 turns into a 300 equivalent at the long end, and the 70-300 turns into a 450, both with no loss of aperture. This already more than gives you the extra effective focal length that you would get from the teleconvertors, which do cause an aperture loss. If you add on the teleconvertor, you're getting 420/510 on the one lens and 630/765 on the other. I suspect that's a longer focal length than you're looking for. A one-stop light loss on a 2.8 lens is acceptable if you're shooting in sufficient light -- meaning outdoors -- but would probably not be acceptable in an indoor venue and would be a non-starter on the 4-5.6 lens. The 4-5.6 lens might very well not autofocus with the teleconvertor because of the loss of light, especially in low light situations. It would almost certainly autofocus way too slowly for sports, assuming it can AF fast enough for sports in the first place.If I were buying a TC I would buy one or the other, not both. I think the 300 f/4 would be the better investment, though. And I would try the lenses you have on the D300 bodies before I would buy anything. You might already have all the focal length you need.</p>

<p>Yes, I was looking at the TC-14E II and TC-17E II.<br>

The lenses are:</p>

<ul>

<li>Nikkor AF 80-200mm f/2.8 ED</li>

<li>Nikkor AF-S VR 70-300 f/4.5-5.6 G IF ED</li>

</ul>

<p>I guess investing in a teleconverter is out of the question. Thanks Shun for your quick response. :(</p>

<p>There are 3rd part TCs which will mount, such as the Kenko, on both these lenses.<br>

But, the gain on the 80-200 is really quite minimal (280mm is not vastly more, check it with your 70-300), and with the 70-300 you can forget about AF with a aperture of f/8. So even with the options that will work, you end up with compromises that just don't really add much, instead only add problems and cost you image quality.<br>

The AF-S 300 f/4 is an excellent lens; but not stellar fast in AF (I think non-scientifically on my D300, about as fast as the AF-D 80-200 f/2.8). But it is a lens I use wide-open without hesitation, also with the TC14. Optically, a gem. It is a bit bigger and heavier than the 80-200, though, and if you use it on a tripod regularly, you owe yourself a replacement tripod collar (which adds another $150 to the bill).</p>

<p>Another take, however, on the point that Craig already raised. You may have what you need already. How large do you print? The 12MP of the D300 and D300s allow for some cropping and still allow pretty large prints.</p>

<p>i just want to chime in and agree with what the other guys have posted. TCs are mostly useful for long, fast prime lenses. they are never at their best on zooms, and on slow, variable-aperture zooms they're practically unusable. you are better off enjoying the "crop" effect of your DX bodies, and not worrying about using your lenses with a TC. most everyone, it seems, momentarily gets excited by the thought of getting super-tele reach on the cheap using a TC, but the fact is, in practice they don't deliver what people hope to achieve -- unless you can deal with a dim viewfinder, slow or no AF, awkward handling, etc. incidentally, there are 3rd party TCs that can mount and AF with either screw-drive and AF-S type AF systems, so the problem isn't so much finding a TC that will attach to your gear, but as noted above, you will not find them productive for sports shooting particularly.</p>

<p>If you looking at spending more than $500, you might add a bit more and find a older AF 300mm f2.8 (D or non-D) Nikkor lens. On a DX body, you end up with a 450mm lens with the crop factor...plus you'll need a decent monopod to support the camera-and-lens combination.</p>

<p> </p>

<p>I use both the 80-200 and the 300 and a Kenko Pro 300 DG 1.4 extendar. Works perfectly well on both lenses. The lenses are used on D2h bodies and the AF on both lenses is quite adequate for sports in my estimation.</p>