TC14B & Tamron SP90/2.8 for increased macro working distance

<p>Does anyone know whether this combination works well or is the TC14B only for 300mm lenses?<br />What would be the downside of this TC on the shorter lens?</p>

<p>PS - I know it won't AF and the body is a D300</p>

<p>Adding 'glass' to a lens often gives no-so-great results. You would end up with a 130-ish mm lens, plus the D300 crop factor. You would have to be the one to try it out ... <strong>be sure to check the D300 manual</strong> that the TC-14B converter is good to use. And since the tele-converter is not AF in nature, the large and spot meters are your choices.</p>

<p> </p>

<blockquote>

<p><em>... <strong>be sure to check the D300 manual</strong></em></p>

</blockquote>

<p>The TC-14B is perfectly "good to use" on the D300, or for that matter <strong>any</strong> 35mm, DX or FX Nikon SLR ever made (although metering will be disabled on "crippled" bodies).</p>

<p>As for how it works (or if it does) with the SP 90/2.8 I have no idea. But it will only mount on lenses that have a recessed rear element, as the front element of the TC-14B extends forward slightly from the mount. The rear throat of the lens also needs to be large enough in diameter to accommodate the front element of the teleconverter.</p>

<p>I get the feeling the rear element won't be recessed enough for the converter.<br>

Steve</p>

 

<p>Hi Clive,<br /><br />This will possibly work, but i'm not really sure about that...<br>

If you still need to buy a TC , it might also be feasable to go for a SIgma 105 or 150mm ?</p>

<p>works well with the Nikon 200mm f4 AIS macro and fits the Sigma 70mm macro whether it fits depends on the rear element...doesn't fit on the Nikon 105 2.8 macro AIS due to the rear glass element...great when you need or want to maintain a distance from skittish subjects</p>

<p>Well, I borrowed a TC14B tonight and can say it does mount behind a 300/4.5 AIS, 80-200/2.8 AFD & Tokina 12-24. Warning, the Tokina will only zoom approx halfway before hitting the TC ...... didn't actually test it but inspection clearly shows this. It will however mount on the 500/8 reflex nikkor-C PROVIDED you remove the 39mm rear filter.</p>

<p>Definately doesn't fit Tamron SP 90/2.8 which is a shame, or the micro 55/2.8 AIS, either the 85/1.4 AIS or 1.8 AFD, not the 50/1.2 AIS or 50/1.8 AFD, nor the 105/2.8 AFD, 180/2.8 AIS ED or any of the 35/2s. Not the 35-70/2.8 AFD or 70-210/4 AFD.</p>

<p>Guess this is what they mean when they say 'Works best on 300mm & longer lenses :)</p>

<p>Guess I'll have to look for the Tamron version TC1.4x.......</p>

<p>I tried the Tamron AF 90 F2.8 macro on the TC14A. I didn't do careful tests, and my memory is not brilliant, but I recall that it was pretty good, which I did not expect. But you'd need to double check this, given the casual nature of my tests. On the 200mm F4 AFD micro the TC14A is atrocious, or at least my copies do not work well together. On the Nikon 60mm F2.8 AF micro it is okay, but not really up to snuff in my opinion.</p>

<p>Really does not seem like a great idea to me. You WILL lose image quality, probably a fair bit. Also you won't gain any magnification (I don't think), the only thing you will gain is working distance. <br>

Almost without doubt you'll get better results with a longer macro lens (like Sigma 180).<br>

Steve</p>

 

<p>Really does not seem like a great idea to me. You WILL lose image quality, probably a fair bit. Also you won't gain any magnification (I don't think), the only thing you will gain is working distance. <br>

Almost without doubt you'll get better results with a longer macro lens (like Sigma 180).<br>

Steve</p>

 

<p>"Also you won't gain any magnification"<br>

You do get increased magnification, and that is one advantage of a TC, along with preserving infinity focus unlike a diopter or tubes. For example, Nikon recommend a 2x TC (I forget which one) to take the 200mm F4 AIS micro from 1:2 to 1:1. The IQ might be iffy though.</p>

<p>Are you sure that's right? The magnification is a factor of the extension vs the focal length AFAIK, so if you double the focal length you won't be able to focus so close because you need more extension.<br>

It's entirely possible I'm wrong about this!<br>

Steve</p>

 

<p>Yes, Leif is 100% correct.</p>

<p>Adding a teleconverter allows you to accomplish one of two things. Bear in mind that a teleconverter does <strong>not</strong> change minimum focus. It changes the focal length of the lens. So a 90mm f/2.8 mated with a 1.4x converter effectively becomes a 126mm f/4 with the same minimum focus as the 90mm lens. Thus you can ...</p>

<ul>

<li>get increased working distance at the same magnification, i.e. at 1:1 you would have more working distance with the lens + teleconverter than with the lens used alone at 1:1 (the focused distance is <strong>different</strong> for each scenario) or ...</li>

<li>increase the magnification (1.4:1 for a 1.4x converter mated to a 1:1 lens) with the same working distance as the master lens used alone at 1:1 (the focused distance is the <strong>same</strong> for each scenario).</li>

</ul>

<p>The penalty is a reduced effective aperture (although the same would be true for an extension tube that gives the equivalent magnification increase) and of course possible compromised optical quality depending on how well the lens and teleconverter are matched.</p>

<p>MMmm Found this :<br>

<a href="http://www.photomacrography.net/photomacrography/Product_Reviews/Tamron90/tamron90.htm">http://www.photomacrography.net/photomacrography/Product_Reviews/Tamron90/tamron90.htm</a><br>

THis guy seems to use a TC on the Tamron to double the magnification or increase shooting distance... He uses a Kenko TC though ( which would make sense on Nikon too, since you keep all connections and functions, and it allows for more protruding back elements on your lenses....).</p>

<p>OK, just tested it, you are right of course (TC14E on 105 micro VR).<br>

Steve</p>

 

<p>You can put an extension ring between the tc14B and the lens, if the lens dosn't have enough free room to accomodate the protruding TC lens. You loose infinity focus but since we are talking about macro this may be worth it. A pk12 may be enough, maybe even the PK11A. If you already have a ring set it is worth a try. Good look, Marco</p>

<blockquote>

<p><em>"A pk12 may be enough, maybe even the PK11A."</em></p>

</blockquote>

<p>I no longer have a TC-14B, but do have a modified TC-14E which is very similar with respect to the front element extension. But if my memory serves me right the PK-12 (14mm) is more than enough to give adequate clearance, but the PK-11A (8mm) is not.</p>